PdfRendererBasic: Modernize the sample am: c87ea8c2ca

am: 9009018ee6

Change-Id: If04f160ef85682680b20968829b1a0ad12520107

28 files changed, 844 insertions, 855 deletions

diff --git a/ui/graphics/PdfRendererBasic/Application/.gitignore b/ui/graphics/PdfRendererBasic/Application/.gitignore
deleted file mode 100644
index 6eb878d4..00000000
--- a/ui/graphics/PdfRendererBasic/Application/.gitignore
+++ /dev/null
@@ -1,16 +0,0 @@
-# Copyright 2013 The Android Open Source Project
-#
-# Licensed under the Apache License, Version 2.0 (the "License");
-# you may not use this file except in compliance with the License.
-# You may obtain a copy of the License at
-#
-# http://www.apache.org/licenses/LICENSE-2.0
-#
-# Unless required by applicable law or agreed to in writing, software
-# distributed under the License is distributed on an "AS IS" BASIS,
-# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-# See the License for the specific language governing permissions and
-# limitations under the License.
-src/template/
-src/common/
-build.gradle
diff --git a/ui/graphics/PdfRendererBasic/Application/build.gradle b/ui/graphics/PdfRendererBasic/Application/build.gradle
new file mode 100644
index 00000000..fa47dfe9
--- /dev/null
+++ b/ui/graphics/PdfRendererBasic/Application/build.gradle
@@ -0,0 +1,56 @@
+/*
+ * Copyright (C) 2019 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+apply plugin: 'com.android.application'
+
+android {
+    compileSdkVersion 28
+
+    defaultConfig {
+        applicationId 'com.example.android.pdfrendererbasic'
+        minSdkVersion 21
+        targetSdkVersion 28
+        versionCode 1
+        versionName '1.0'
+        testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
+    }
+
+    compileOptions {
+        sourceCompatibility JavaVersion.VERSION_1_8
+        targetCompatibility JavaVersion.VERSION_1_8
+    }
+
+    testOptions {
+        unitTests {
+            returnDefaultValues = true
+            includeAndroidResources = true
+        }
+    }
+}
+
+dependencies {
+    implementation 'androidx.appcompat:appcompat:1.0.2'
+
+    def lifecycle_version = '2.0.0'
+    implementation "androidx.lifecycle:lifecycle-extensions:$lifecycle_version"
+    androidTestImplementation "androidx.arch.core:core-testing:$lifecycle_version"
+
+    testImplementation 'com.google.truth:truth:0.42'
+    testImplementation 'androidx.test:core:1.1.0'
+    testImplementation 'androidx.test:runner:1.1.1'
+    androidTestImplementation 'androidx.test.ext:truth:1.1.0'
+    androidTestImplementation 'androidx.test.espresso:espresso-core:3.1.1'
+}
diff --git a/ui/graphics/PdfRendererBasic/Application/src/androidTest/java/com/example/android/pdfrendererbasic/PdfRendererBasicTest.java b/ui/graphics/PdfRendererBasic/Application/src/androidTest/java/com/example/android/pdfrendererbasic/PdfRendererBasicTest.java
new file mode 100644
index 00000000..105034b6
--- /dev/null
+++ b/ui/graphics/PdfRendererBasic/Application/src/androidTest/java/com/example/android/pdfrendererbasic/PdfRendererBasicTest.java
@@ -0,0 +1,66 @@
+/*
+ * Copyright (C) 2019 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.example.android.pdfrendererbasic;
+
+import org.junit.Test;
+import org.junit.runner.RunWith;
+
+import androidx.fragment.app.Fragment;
+import androidx.test.core.app.ActivityScenario;
+import androidx.test.filters.LargeTest;
+import androidx.test.runner.AndroidJUnit4;
+
+import static androidx.test.espresso.Espresso.onView;
+import static androidx.test.espresso.action.ViewActions.click;
+import static androidx.test.espresso.assertion.ViewAssertions.matches;
+import static androidx.test.espresso.matcher.ViewMatchers.isDisplayed;
+import static androidx.test.espresso.matcher.ViewMatchers.isEnabled;
+import static androidx.test.espresso.matcher.ViewMatchers.withId;
+import static androidx.test.espresso.matcher.ViewMatchers.withText;
+import static com.google.common.truth.Truth.assertThat;
+import static org.hamcrest.CoreMatchers.not;
+import static org.hamcrest.core.AllOf.allOf;
+
+@RunWith(AndroidJUnit4.class)
+@LargeTest
+public class PdfRendererBasicTest {
+
+    @Test
+    public void integration() {
+        final ActivityScenario<MainActivity> scenario = ActivityScenario.launch(MainActivity.class);
+        scenario.onActivity((activity) -> {
+            final Fragment fragment = activity.getSupportFragmentManager()
+                    .findFragmentById(R.id.container);
+            assertThat(fragment).isInstanceOf(PdfRendererBasicFragment.class);
+        });
+        onView(withId(R.id.image)).check(matches(isDisplayed()));
+        onView(withId(R.id.previous)).check(matches(allOf(isDisplayed(), not(isEnabled()))));
+        onView(withId(R.id.next)).check(matches(allOf(isDisplayed(), isEnabled())));
+        onView(withText("PdfRendererBasic (1/10)")).check(matches(isDisplayed()));
+        onView(withId(R.id.next)).perform(click());
+        onView(withText("PdfRendererBasic (2/10)")).check(matches(isDisplayed()));
+        onView(withId(R.id.previous)).check(matches(allOf(isDisplayed(), isEnabled())));
+        onView(withId(R.id.next)).check(matches(allOf(isDisplayed(), isEnabled())));
+        for (int i = 0; i < 8; i++) {
+            onView(withId(R.id.next)).perform(click());
+        }
+        onView(withText("PdfRendererBasic (10/10)")).check(matches(isDisplayed()));
+        onView(withId(R.id.previous)).check(matches(allOf(isDisplayed(), isEnabled())));
+        onView(withId(R.id.next)).check(matches(allOf(isDisplayed(), not(isEnabled()))));
+    }
+
+}
diff --git a/ui/graphics/PdfRendererBasic/Application/src/androidTest/java/com/example/android/pdfrendererbasic/PdfRendererBasicViewModelTest.java b/ui/graphics/PdfRendererBasic/Application/src/androidTest/java/com/example/android/pdfrendererbasic/PdfRendererBasicViewModelTest.java
new file mode 100644
index 00000000..bd1d5d86
--- /dev/null
+++ b/ui/graphics/PdfRendererBasic/Application/src/androidTest/java/com/example/android/pdfrendererbasic/PdfRendererBasicViewModelTest.java
@@ -0,0 +1,62 @@
+/*
+ * Copyright (C) 2019 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.example.android.pdfrendererbasic;
+
+import org.junit.Rule;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+
+import androidx.arch.core.executor.testing.InstantTaskExecutorRule;
+import androidx.test.core.app.ApplicationProvider;
+import androidx.test.filters.MediumTest;
+import androidx.test.runner.AndroidJUnit4;
+
+import static com.google.common.truth.Truth.assertThat;
+
+@RunWith(AndroidJUnit4.class)
+@MediumTest
+public class PdfRendererBasicViewModelTest {
+
+    @Rule
+    public final InstantTaskExecutorRule rule = new InstantTaskExecutorRule();
+
+    private PdfRendererBasicViewModel mViewModel = new PdfRendererBasicViewModel(
+            ApplicationProvider.getApplicationContext(), true);
+
+    @Test
+    public void allPages() {
+        assertThat(mViewModel).isNotNull();
+        final PdfRendererBasicViewModel.PageInfo firstInfo = mViewModel.getPageInfo().getValue();
+        assertThat(firstInfo).isNotNull();
+        assertThat(firstInfo.index).isEqualTo(0);
+        assertThat(firstInfo.count).isEqualTo(10);
+        assertThat(mViewModel.getPreviousEnabled().getValue()).isFalse();
+        assertThat(mViewModel.getNextEnabled().getValue()).isTrue();
+        assertThat(mViewModel.getPageBitmap().getValue()).isNotNull();
+        for (int i = 0; i < 9; i++) {
+            mViewModel.showNext();
+        }
+        final PdfRendererBasicViewModel.PageInfo lastInfo = mViewModel.getPageInfo().getValue();
+        assertThat(lastInfo).isNotNull();
+        assertThat(lastInfo.index).isEqualTo(9);
+        assertThat(lastInfo.count).isEqualTo(10);
+        assertThat(mViewModel.getPreviousEnabled().getValue()).isTrue();
+        assertThat(mViewModel.getNextEnabled().getValue()).isFalse();
+        assertThat(mViewModel.getPageBitmap().getValue()).isNotNull();
+    }
+
+}
diff --git a/ui/graphics/PdfRendererBasic/Application/src/main/AndroidManifest.xml b/ui/graphics/PdfRendererBasic/Application/src/main/AndroidManifest.xml
index 276c4bea..d320d211 100644
--- a/ui/graphics/PdfRendererBasic/Application/src/main/AndroidManifest.xml
+++ b/ui/graphics/PdfRendererBasic/Application/src/main/AndroidManifest.xml
@@ -14,19 +14,21 @@
  See the License for the specific language governing permissions and
  limitations under the License.
 -->
+<manifest
+    xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:tools="http://schemas.android.com/tools"
+    package="com.example.android.pdfrendererbasic">
 
-<manifest xmlns:android="http://schemas.android.com/apk/res/android"
-    package="com.example.android.pdfrendererbasic"
-    android:versionCode="1"
-    android:versionName="1.0">
-
-    <application android:allowBackup="true"
-        android:label="@string/app_name"
+    <application
+        android:allowBackup="false"
         android:icon="@mipmap/ic_launcher"
-        android:theme="@style/Theme.PdfRendererBasic">
+        android:label="@string/app_name"
+        android:theme="@style/Theme.PdfRendererBasic"
+        tools:ignore="GoogleAppIndexingWarning">
 
-        <activity android:name=".MainActivity"
-                  android:label="@string/app_name">
+        <activity
+            android:name=".MainActivity"
+            android:label="@string/app_name">
             <intent-filter>
                 <action android:name="android.intent.action.MAIN" />
                 <category android:name="android.intent.category.LAUNCHER" />
@@ -34,5 +36,4 @@
         </activity>
     </application>
 
-
 </manifest>
diff --git a/ui/graphics/PdfRendererBasic/Application/src/main/java/com/example/android/pdfrendererbasic/MainActivity.java b/ui/graphics/PdfRendererBasic/Application/src/main/java/com/example/android/pdfrendererbasic/MainActivity.java
index 25781b79..0a59b7bb 100644
--- a/ui/graphics/PdfRendererBasic/Application/src/main/java/com/example/android/pdfrendererbasic/MainActivity.java
+++ b/ui/graphics/PdfRendererBasic/Application/src/main/java/com/example/android/pdfrendererbasic/MainActivity.java
@@ -16,25 +16,29 @@
 
 package com.example.android.pdfrendererbasic;
 
-import android.app.AlertDialog;
+import android.app.Dialog;
 import android.os.Bundle;
-import android.support.v7.app.AppCompatActivity;
 import android.view.Menu;
 import android.view.MenuItem;
 
+import androidx.annotation.NonNull;
+import androidx.annotation.Nullable;
+import androidx.appcompat.app.AlertDialog;
+import androidx.appcompat.app.AppCompatActivity;
+import androidx.fragment.app.DialogFragment;
+
 public class MainActivity extends AppCompatActivity {
 
-    public static final String FRAGMENT_PDF_RENDERER_BASIC = "pdf_renderer_basic";
+    private static final String FRAGMENT_INFO = "info";
 
     @Override
     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
-        setContentView(R.layout.activity_main_real);
+        setContentView(R.layout.main_activity);
         if (savedInstanceState == null) {
             getSupportFragmentManager().beginTransaction()
-                    .add(R.id.container, new PdfRendererBasicFragment(),
-                            FRAGMENT_PDF_RENDERER_BASIC)
-                    .commit();
+                    .add(R.id.container, new PdfRendererBasicFragment())
+                    .commitNow();
         }
     }
 
@@ -48,12 +52,23 @@ public class MainActivity extends AppCompatActivity {
     public boolean onOptionsItemSelected(MenuItem item) {
         switch (item.getItemId()) {
             case R.id.action_info:
-                new AlertDialog.Builder(this)
-                        .setMessage(R.string.intro_message)
-                        .setPositiveButton(android.R.string.ok, null)
-                        .show();
+                new InfoDialogFragment().show(getSupportFragmentManager(), FRAGMENT_INFO);
                 return true;
         }
         return super.onOptionsItemSelected(item);
     }
+
+    public static class InfoDialogFragment extends DialogFragment {
+
+        @NonNull
+        @Override
+        public Dialog onCreateDialog(@Nullable Bundle savedInstanceState) {
+            return new AlertDialog.Builder(requireContext())
+                    .setMessage(R.string.intro_message)
+                    .setPositiveButton(android.R.string.ok, null)
+                    .show();
+        }
+
+    }
+
 }
diff --git a/ui/graphics/PdfRendererBasic/Application/src/main/java/com/example/android/pdfrendererbasic/PdfRendererBasicFragment.java b/ui/graphics/PdfRendererBasic/Application/src/main/java/com/example/android/pdfrendererbasic/PdfRendererBasicFragment.java
index 98f16941..2a933716 100644
--- a/ui/graphics/PdfRendererBasic/Application/src/main/java/com/example/android/pdfrendererbasic/PdfRendererBasicFragment.java
+++ b/ui/graphics/PdfRendererBasic/Application/src/main/java/com/example/android/pdfrendererbasic/PdfRendererBasicFragment.java
@@ -16,235 +16,75 @@
 
 package com.example.android.pdfrendererbasic;
 
-import android.content.Context;
-import android.graphics.Bitmap;
-import android.graphics.pdf.PdfRenderer;
+import android.app.Activity;
 import android.os.Bundle;
-import android.os.ParcelFileDescriptor;
-import android.support.v4.app.Fragment;
 import android.view.LayoutInflater;
 import android.view.View;
 import android.view.ViewGroup;
 import android.widget.Button;
 import android.widget.ImageView;
-import android.widget.Toast;
 
-import java.io.File;
-import java.io.FileOutputStream;
-import java.io.IOException;
-import java.io.InputStream;
+import androidx.annotation.NonNull;
+import androidx.fragment.app.Fragment;
+import androidx.lifecycle.LifecycleOwner;
+import androidx.lifecycle.ViewModelProviders;
 
 /**
- * This fragment has a big {@ImageView} that shows PDF pages, and 2
- * {@link android.widget.Button}s to move between pages. We use a
- * {@link android.graphics.pdf.PdfRenderer} to render PDF pages as
- * {@link android.graphics.Bitmap}s.
+ * This fragment has a big {@link ImageView} that shows PDF pages, and 2
+ * {@link android.widget.Button}s to move between pages.
  */
-public class PdfRendererBasicFragment extends Fragment implements View.OnClickListener {
+public class PdfRendererBasicFragment extends Fragment {
 
-    /**
-     * Key string for saving the state of current page index.
-     */
-    private static final String STATE_CURRENT_PAGE_INDEX = "current_page_index";
+    private PdfRendererBasicViewModel mViewModel;
 
-    /**
-     * The filename of the PDF.
-     */
-    private static final String FILENAME = "sample.pdf";
-
-    /**
-     * File descriptor of the PDF.
-     */
-    private ParcelFileDescriptor mFileDescriptor;
-
-    /**
-     * {@link android.graphics.pdf.PdfRenderer} to render the PDF.
-     */
-    private PdfRenderer mPdfRenderer;
-
-    /**
-     * Page that is currently shown on the screen.
-     */
-    private PdfRenderer.Page mCurrentPage;
-
-    /**
-     * {@link android.widget.ImageView} that shows a PDF page as a {@link android.graphics.Bitmap}
-     */
-    private ImageView mImageView;
-
-    /**
-     * {@link android.widget.Button} to move to the previous page.
-     */
-    private Button mButtonPrevious;
-
-    /**
-     * {@link android.widget.Button} to move to the next page.
-     */
-    private Button mButtonNext;
-
-    /**
-     * PDF page index
-     */
-    private int mPageIndex;
-
-    public PdfRendererBasicFragment() {
-    }
-
-    @Override
-    public View onCreateView(LayoutInflater inflater, ViewGroup container,
-                             Bundle savedInstanceState) {
-        return inflater.inflate(R.layout.fragment_pdf_renderer_basic, container, false);
-    }
-
-    @Override
-    public void onViewCreated(View view, Bundle savedInstanceState) {
-        super.onViewCreated(view, savedInstanceState);
-        // Retain view references.
-        mImageView = (ImageView) view.findViewById(R.id.image);
-        mButtonPrevious = (Button) view.findViewById(R.id.previous);
-        mButtonNext = (Button) view.findViewById(R.id.next);
-        // Bind events.
-        mButtonPrevious.setOnClickListener(this);
-        mButtonNext.setOnClickListener(this);
-
-        mPageIndex = 0;
-        // If there is a savedInstanceState (screen orientations, etc.), we restore the page index.
-        if (null != savedInstanceState) {
-            mPageIndex = savedInstanceState.getInt(STATE_CURRENT_PAGE_INDEX, 0);
-        }
-    }
-
-    @Override
-    public void onStart() {
-        super.onStart();
-        try {
-            openRenderer(getActivity());
-            showPage(mPageIndex);
-        } catch (IOException e) {
-            e.printStackTrace();
-            Toast.makeText(getActivity(), "Error! " + e.getMessage(), Toast.LENGTH_SHORT).show();
-        }
-    }
-
-    @Override
-    public void onStop() {
-        try {
-            closeRenderer();
-        } catch (IOException e) {
-            e.printStackTrace();
+    private final View.OnClickListener mOnClickListener = (view) -> {
+        switch (view.getId()) {
+            case R.id.previous:
+                if (mViewModel != null) {
+                    mViewModel.showPrevious();
+                }
+                break;
+            case R.id.next:
+                if (mViewModel != null) {
+                    mViewModel.showNext();
+                }
+                break;
         }
-        super.onStop();
-    }
+    };
 
     @Override
-    public void onSaveInstanceState(Bundle outState) {
-        super.onSaveInstanceState(outState);
-        if (null != mCurrentPage) {
-            outState.putInt(STATE_CURRENT_PAGE_INDEX, mCurrentPage.getIndex());
-        }
-    }
-
-    /**
-     * Sets up a {@link android.graphics.pdf.PdfRenderer} and related resources.
-     */
-    private void openRenderer(Context context) throws IOException {
-        // In this sample, we read a PDF from the assets directory.
-        File file = new File(context.getCacheDir(), FILENAME);
-        if (!file.exists()) {
-            // Since PdfRenderer cannot handle the compressed asset file directly, we copy it into
-            // the cache directory.
-            InputStream asset = context.getAssets().open(FILENAME);
-            FileOutputStream output = new FileOutputStream(file);
-            final byte[] buffer = new byte[1024];
-            int size;
-            while ((size = asset.read(buffer)) != -1) {
-                output.write(buffer, 0, size);
-            }
-            asset.close();
-            output.close();
-        }
-        mFileDescriptor = ParcelFileDescriptor.open(file, ParcelFileDescriptor.MODE_READ_ONLY);
-        // This is the PdfRenderer we use to render the PDF.
-        if (mFileDescriptor != null) {
-            mPdfRenderer = new PdfRenderer(mFileDescriptor);
-        }
-    }
-
-    /**
-     * Closes the {@link android.graphics.pdf.PdfRenderer} and related resources.
-     *
-     * @throws java.io.IOException When the PDF file cannot be closed.
-     */
-    private void closeRenderer() throws IOException {
-        if (null != mCurrentPage) {
-            mCurrentPage.close();
-        }
-        mPdfRenderer.close();
-        mFileDescriptor.close();
-    }
-
-    /**
-     * Shows the specified page of PDF to the screen.
-     *
-     * @param index The page index.
-     */
-    private void showPage(int index) {
-        if (mPdfRenderer.getPageCount() <= index) {
-            return;
-        }
-        // Make sure to close the current page before opening another one.
-        if (null != mCurrentPage) {
-            mCurrentPage.close();
-        }
-        // Use `openPage` to open a specific page in PDF.
-        mCurrentPage = mPdfRenderer.openPage(index);
-        // Important: the destination bitmap must be ARGB (not RGB).
-        Bitmap bitmap = Bitmap.createBitmap(mCurrentPage.getWidth(), mCurrentPage.getHeight(),
-                Bitmap.Config.ARGB_8888);
-        // Here, we render the page onto the Bitmap.
-        // To render a portion of the page, use the second and third parameter. Pass nulls to get
-        // the default result.
-        // Pass either RENDER_MODE_FOR_DISPLAY or RENDER_MODE_FOR_PRINT for the last parameter.
-        mCurrentPage.render(bitmap, null, null, PdfRenderer.Page.RENDER_MODE_FOR_DISPLAY);
-        // We are ready to show the Bitmap to user.
-        mImageView.setImageBitmap(bitmap);
-        updateUi();
-    }
-
-    /**
-     * Updates the state of 2 control buttons in response to the current page index.
-     */
-    private void updateUi() {
-        int index = mCurrentPage.getIndex();
-        int pageCount = mPdfRenderer.getPageCount();
-        mButtonPrevious.setEnabled(0 != index);
-        mButtonNext.setEnabled(index + 1 < pageCount);
-        getActivity().setTitle(getString(R.string.app_name_with_index, index + 1, pageCount));
-    }
-
-    /**
-     * Gets the number of pages in the PDF. This method is marked as public for testing.
-     *
-     * @return The number of pages.
-     */
-    public int getPageCount() {
-        return mPdfRenderer.getPageCount();
+    public View onCreateView(@NonNull LayoutInflater inflater, ViewGroup container,
+                             Bundle savedInstanceState) {
+        return inflater.inflate(R.layout.pdf_renderer_basic_fragment, container, false);
     }
 
     @Override
-    public void onClick(View view) {
-        switch (view.getId()) {
-            case R.id.previous: {
-                // Move to the previous page
-                showPage(mCurrentPage.getIndex() - 1);
-                break;
+    public void onViewCreated(@NonNull View view, Bundle savedInstanceState) {
+        // View references.
+        final ImageView image = view.findViewById(R.id.image);
+        final Button buttonPrevious = view.findViewById(R.id.previous);
+        final Button buttonNext = view.findViewById(R.id.next);
+
+        // Bind data.
+        mViewModel = ViewModelProviders.of(this).get(PdfRendererBasicViewModel.class);
+        final LifecycleOwner viewLifecycleOwner = getViewLifecycleOwner();
+        mViewModel.getPageInfo().observe(viewLifecycleOwner, pageInfo -> {
+            if (pageInfo == null) {
+                return;
             }
-            case R.id.next: {
-                // Move to the next page
-                showPage(mCurrentPage.getIndex() + 1);
-                break;
+            final Activity activity = getActivity();
+            if (activity != null) {
+                activity.setTitle(getString(R.string.app_name_with_index,
+                        pageInfo.index + 1, pageInfo.count));
             }
-        }
+        });
+        mViewModel.getPageBitmap().observe(viewLifecycleOwner, image::setImageBitmap);
+        mViewModel.getPreviousEnabled().observe(viewLifecycleOwner, buttonPrevious::setEnabled);
+        mViewModel.getNextEnabled().observe(viewLifecycleOwner, buttonNext::setEnabled);
+
+        // Bind events.
+        buttonPrevious.setOnClickListener(mOnClickListener);
+        buttonNext.setOnClickListener(mOnClickListener);
     }
 
 }
diff --git a/ui/graphics/PdfRendererBasic/Application/src/main/java/com/example/android/pdfrendererbasic/PdfRendererBasicViewModel.java b/ui/graphics/PdfRendererBasic/Application/src/main/java/com/example/android/pdfrendererbasic/PdfRendererBasicViewModel.java
new file mode 100644
index 00000000..cb638c04
--- /dev/null
+++ b/ui/graphics/PdfRendererBasic/Application/src/main/java/com/example/android/pdfrendererbasic/PdfRendererBasicViewModel.java
@@ -0,0 +1,205 @@
+/*
+ * Copyright (C) 2019 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.example.android.pdfrendererbasic;
+
+import android.app.Application;
+import android.graphics.Bitmap;
+import android.graphics.pdf.PdfRenderer;
+import android.os.ParcelFileDescriptor;
+import android.util.Log;
+
+import java.io.File;
+import java.io.FileOutputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.util.concurrent.Executor;
+import java.util.concurrent.Executors;
+
+import androidx.annotation.WorkerThread;
+import androidx.lifecycle.AndroidViewModel;
+import androidx.lifecycle.LiveData;
+import androidx.lifecycle.MutableLiveData;
+
+/**
+ * This holds all the data we need for this sample app.
+ * <p>
+ * We use a {@link android.graphics.pdf.PdfRenderer} to render PDF pages as
+ * {@link android.graphics.Bitmap}s.
+ */
+public class PdfRendererBasicViewModel extends AndroidViewModel {
+
+    private static final String TAG = "PdfRendererBasic";
+
+    /**
+     * The filename of the PDF.
+     */
+    private static final String FILENAME = "sample.pdf";
+
+    private final MutableLiveData<PageInfo> mPageInfo = new MutableLiveData<>();
+    private final MutableLiveData<Bitmap> mPageBitmap = new MutableLiveData<>();
+    private final MutableLiveData<Boolean> mPreviousEnabled = new MutableLiveData<>();
+    private final MutableLiveData<Boolean> mNextEnabled = new MutableLiveData<>();
+
+    private final Executor mExecutor;
+    private ParcelFileDescriptor mFileDescriptor;
+    private PdfRenderer mPdfRenderer;
+    private PdfRenderer.Page mCurrentPage;
+    private boolean mCleared;
+
+    @SuppressWarnings("unused")
+    public PdfRendererBasicViewModel(Application application) {
+        this(application, false);
+    }
+
+    PdfRendererBasicViewModel(Application application, boolean useInstantExecutor) {
+        super(application);
+        if (useInstantExecutor) {
+            mExecutor = Runnable::run;
+        } else {
+            mExecutor = Executors.newSingleThreadExecutor();
+        }
+        mExecutor.execute(() -> {
+            try {
+                openPdfRenderer();
+                showPage(0);
+                if (mCleared) {
+                    closePdfRenderer();
+                }
+            } catch (IOException e) {
+                Log.e(TAG, "Failed to open PdfRenderer", e);
+            }
+        });
+    }
+
+    @Override
+    protected void onCleared() {
+        super.onCleared();
+        mExecutor.execute(() -> {
+            try {
+                closePdfRenderer();
+                mCleared = true;
+            } catch (IOException e) {
+                Log.i(TAG, "Failed to close PdfRenderer", e);
+            }
+        });
+    }
+
+    LiveData<PageInfo> getPageInfo() {
+        return mPageInfo;
+    }
+
+    LiveData<Bitmap> getPageBitmap() {
+        return mPageBitmap;
+    }
+
+    LiveData<Boolean> getPreviousEnabled() {
+        return mPreviousEnabled;
+    }
+
+    LiveData<Boolean> getNextEnabled() {
+        return mNextEnabled;
+    }
+
+    void showPrevious() {
+        if (mPdfRenderer == null || mCurrentPage == null) {
+            return;
+        }
+        final int index = mCurrentPage.getIndex();
+        if (index > 0) {
+            mExecutor.execute(() -> showPage(index - 1));
+        }
+    }
+
+    void showNext() {
+        if (mPdfRenderer == null || mCurrentPage == null) {
+            return;
+        }
+        final int index = mCurrentPage.getIndex();
+        if (index + 1 < mPdfRenderer.getPageCount()) {
+            mExecutor.execute(() -> showPage(index + 1));
+        }
+    }
+
+    @WorkerThread
+    private void openPdfRenderer() throws IOException {
+        final File file = new File(getApplication().getCacheDir(), FILENAME);
+        if (!file.exists()) {
+            // Since PdfRenderer cannot handle the compressed asset file directly, we copy it into
+            // the cache directory.
+            final InputStream asset = getApplication().getAssets().open(FILENAME);
+            final FileOutputStream output = new FileOutputStream(file);
+            final byte[] buffer = new byte[1024];
+            int size;
+            while ((size = asset.read(buffer)) != -1) {
+                output.write(buffer, 0, size);
+            }
+            asset.close();
+            output.close();
+        }
+        mFileDescriptor = ParcelFileDescriptor.open(file, ParcelFileDescriptor.MODE_READ_ONLY);
+        if (mFileDescriptor != null) {
+            mPdfRenderer = new PdfRenderer(mFileDescriptor);
+        }
+    }
+
+    @WorkerThread
+    private void closePdfRenderer() throws IOException {
+        if (mCurrentPage != null) {
+            mCurrentPage.close();
+        }
+        if (mPdfRenderer != null) {
+            mPdfRenderer.close();
+        }
+        if (mFileDescriptor != null) {
+            mFileDescriptor.close();
+        }
+    }
+
+    @WorkerThread
+    private void showPage(int index) {
+        // Make sure to close the current page before opening another one.
+        if (null != mCurrentPage) {
+            mCurrentPage.close();
+        }
+        // Use `openPage` to open a specific page in PDF.
+        mCurrentPage = mPdfRenderer.openPage(index);
+        // Important: the destination bitmap must be ARGB (not RGB).
+        final Bitmap bitmap = Bitmap.createBitmap(mCurrentPage.getWidth(), mCurrentPage.getHeight(),
+                Bitmap.Config.ARGB_8888);
+        // Here, we render the page onto the Bitmap.
+        // To render a portion of the page, use the second and third parameter. Pass nulls to get
+        // the default result.
+        // Pass either RENDER_MODE_FOR_DISPLAY or RENDER_MODE_FOR_PRINT for the last parameter.
+        mCurrentPage.render(bitmap, null, null, PdfRenderer.Page.RENDER_MODE_FOR_DISPLAY);
+        mPageBitmap.postValue(bitmap);
+        final int count = mPdfRenderer.getPageCount();
+        mPageInfo.postValue(new PageInfo(index, count));
+        mPreviousEnabled.postValue(index > 0);
+        mNextEnabled.postValue(index + 1 < count);
+    }
+
+    static class PageInfo {
+        final int index;
+        final int count;
+
+        PageInfo(int index, int count) {
+            this.index = index;
+            this.count = count;
+        }
+    }
+
+}
diff --git a/ui/graphics/PdfRendererBasic/Application/src/main/res/layout/activity_main_real.xml b/ui/graphics/PdfRendererBasic/Application/src/main/res/layout/main_activity.xml
index dcd52bea..60a42be2 100644
--- a/ui/graphics/PdfRendererBasic/Application/src/main/res/layout/activity_main_real.xml
+++ b/ui/graphics/PdfRendererBasic/Application/src/main/res/layout/main_activity.xml
@@ -14,10 +14,10 @@
   See the License for the specific language governing permissions and
   limitations under the License.
 -->
-<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
+<FrameLayout
+    xmlns:android="http://schemas.android.com/apk/res/android"
     xmlns:tools="http://schemas.android.com/tools"
     android:id="@+id/container"
     android:layout_width="match_parent"
     android:layout_height="match_parent"
-    tools:context=".MainActivity"
-    tools:ignore="MergeRootFrame" />
+    tools:context=".MainActivity" />
diff --git a/ui/graphics/PdfRendererBasic/Application/src/main/res/layout/fragment_pdf_renderer_basic.xml b/ui/graphics/PdfRendererBasic/Application/src/main/res/layout/pdf_renderer_basic_fragment.xml
index 7ecfac36..7ecfac36 100644
--- a/ui/graphics/PdfRendererBasic/Application/src/main/res/layout/fragment_pdf_renderer_basic.xml
+++ b/ui/graphics/PdfRendererBasic/Application/src/main/res/layout/pdf_renderer_basic_fragment.xml
diff --git a/ui/graphics/PdfRendererBasic/Application/src/main/res/values/strings.xml b/ui/graphics/PdfRendererBasic/Application/src/main/res/values/strings.xml
index e0182fd3..995a82e9 100644
--- a/ui/graphics/PdfRendererBasic/Application/src/main/res/values/strings.xml
+++ b/ui/graphics/PdfRendererBasic/Application/src/main/res/values/strings.xml
@@ -16,7 +16,9 @@
 -->
 <resources>
 
+    <string name="app_name">PdfRendererBasic</string>
     <string name="app_name_with_index">PdfRendererBasic (%1$d/%2$d)</string>
+    <string name="intro_message">This sample demonstrates how to use PdfRenderer to display PDF documents on the screen.</string>
     <string name="info">Info</string>
     <string name="previous">Previous</string>
     <string name="next">Next</string>
diff --git a/ui/graphics/PdfRendererBasic/Application/tests/AndroidManifest.xml b/ui/graphics/PdfRendererBasic/Application/tests/AndroidManifest.xml
deleted file mode 100644
index 54829c78..00000000
--- a/ui/graphics/PdfRendererBasic/Application/tests/AndroidManifest.xml
+++ /dev/null
@@ -1,41 +0,0 @@
-<?xml version="1.0" encoding="utf-8"?>
-<!--
-  Copyright (C) 2014 The Android Open Source Project
-
-  Licensed under the Apache License, Version 2.0 (the "License");
-  you may not use this file except in compliance with the License.
-  You may obtain a copy of the License at
-
-      http://www.apache.org/licenses/LICENSE-2.0
-
-  Unless required by applicable law or agreed to in writing, software
-  distributed under the License is distributed on an "AS IS" BASIS,
-  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-  See the License for the specific language governing permissions and
-  limitations under the License.
-  -->
-<!-- package name must be unique so suffix with "tests" so package loader doesn't ignore us -->
-<manifest
-    package="com.example.android.pdfrendererbasic.tests"
-    xmlns:android="http://schemas.android.com/apk/res/android"
-    android:versionCode="1"
-    android:versionName="1.0">
-
-    <!-- Min/target SDK versions (<uses-sdk>) managed by build.gradle -->
-
-    <!-- We add an application tag here just so that we can indicate that
-         this package needs to link against the android.test library,
-         which is needed when building test cases. -->
-    <application>
-        <uses-library android:name="android.test.runner"/>
-    </application>
-
-    <!--
-    Specifies the instrumentation test runner used to run the tests.
-    -->
-    <instrumentation
-        android:name="android.test.InstrumentationTestRunner"
-        android:label="Tests for com.example.android.pdfrendererbasic"
-        android:targetPackage="com.example.android.pdfrendererbasic"/>
-
-</manifest>
diff --git a/ui/graphics/PdfRendererBasic/Application/tests/src/com/example/android/pdfrendererbasic/tests/PdfRendererBasicFragmentTests.java b/ui/graphics/PdfRendererBasic/Application/tests/src/com/example/android/pdfrendererbasic/tests/PdfRendererBasicFragmentTests.java
deleted file mode 100644
index 0f94cbf8..00000000
--- a/ui/graphics/PdfRendererBasic/Application/tests/src/com/example/android/pdfrendererbasic/tests/PdfRendererBasicFragmentTests.java
+++ /dev/null
@@ -1,132 +0,0 @@
-/*
- * Copyright (C) 2014 The Android Open Source Project
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *      http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-package com.example.android.pdfrendererbasic.tests;
-
-import android.content.pm.ActivityInfo;
-import android.test.ActivityInstrumentationTestCase2;
-import android.test.TouchUtils;
-import android.test.suitebuilder.annotation.LargeTest;
-import android.view.View;
-import android.widget.Button;
-
-import com.example.android.pdfrendererbasic.MainActivity;
-import com.example.android.pdfrendererbasic.PdfRendererBasicFragment;
-import com.example.android.pdfrendererbasic.R;
-
-/**
- * Tests for PdfRendererBasic sample.
- */
-public class PdfRendererBasicFragmentTests extends ActivityInstrumentationTestCase2<MainActivity> {
-
-    private MainActivity mActivity;
-    private PdfRendererBasicFragment mFragment;
-
-    private Button mButtonPrevious;
-    private Button mButtonNext;
-
-    public PdfRendererBasicFragmentTests() {
-        super(MainActivity.class);
-    }
-
-    @Override
-    protected void setUp() throws Exception {
-        super.setUp();
-        mActivity = getActivity();
-        mFragment = (PdfRendererBasicFragment) mActivity.getFragmentManager()
-                .findFragmentByTag(MainActivity.FRAGMENT_PDF_RENDERER_BASIC);
-    }
-
-    @LargeTest
-    public void testActivityTitle() {
-        // The title of the activity should be "PdfRendererBasic (1/10)" at first
-        String expectedActivityTitle = mActivity.getString(R.string.app_name_with_index, 1,
-                mFragment.getPageCount());
-        assertEquals(expectedActivityTitle, mActivity.getTitle());
-    }
-
-    @LargeTest
-    public void testButtons_previousDisabledAtFirst() {
-        setUpButtons();
-        // Check that the previous button is disabled at first
-        assertFalse(mButtonPrevious.isEnabled());
-        // The next button should be enabled
-        assertTrue(mButtonNext.isEnabled());
-    }
-
-    @LargeTest
-    public void testButtons_bothEnabledInMiddle() {
-        setUpButtons();
-        turnPages(1);
-        // Two buttons should be both enabled
-        assertTrue(mButtonPrevious.isEnabled());
-        assertTrue(mButtonNext.isEnabled());
-    }
-
-    @LargeTest
-    public void testButtons_nextDisabledLastPage() {
-        setUpButtons();
-        int pageCount = mFragment.getPageCount();
-        // Click till it reaches the last page
-        turnPages(pageCount - 1);
-        // Check the page count
-        String expectedActivityTitle = mActivity.getString(R.string.app_name_with_index,
-                pageCount, pageCount);
-        assertEquals(expectedActivityTitle, mActivity.getTitle());
-        // The previous button should be enabled
-        assertTrue(mButtonPrevious.isEnabled());
-        // Check that the next button is disabled
-        assertFalse(mButtonNext.isEnabled());
-    }
-
-    @LargeTest
-    public void testOrientationChangePreserveState() {
-        mActivity.setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_PORTRAIT);
-        setUpButtons();
-        turnPages(1);
-        int pageCount = mFragment.getPageCount();
-        String expectedActivityTitle = mActivity.getString(R.string.app_name_with_index,
-                2, pageCount);
-        assertEquals(expectedActivityTitle, mActivity.getTitle());
-        mActivity.setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_LANDSCAPE);
-        // Check that the title is the same after orientation change
-        assertEquals(expectedActivityTitle, mActivity.getTitle());
-    }
-
-    /**
-     * Prepares references to the buttons "Previous" and "Next".
-     */
-    private void setUpButtons() {
-        View view = mFragment.getView();
-        assertNotNull(view);
-        mButtonPrevious = (Button) view.findViewById(R.id.previous);
-        assertNotNull(mButtonPrevious);
-        mButtonNext = (Button) view.findViewById(R.id.next);
-        assertNotNull(mButtonNext);
-    }
-
-    /**
-     * Click the "Next" button to turn the pages.
-     *
-     * @param count The number of times to turn pages.
-     */
-    private void turnPages(int count) {
-        for (int i = 0; i < count; ++i) {
-            TouchUtils.clickView(this, mButtonNext);
-        }
-    }
-
-}
diff --git a/ui/graphics/PdfRendererBasic/build.gradle b/ui/graphics/PdfRendererBasic/build.gradle
index be1fa823..93ddf8c4 100644
--- a/ui/graphics/PdfRendererBasic/build.gradle
+++ b/ui/graphics/PdfRendererBasic/build.gradle
@@ -1,14 +1,29 @@
+buildscript {
+    repositories {
+        google()
+        jcenter()
+    }
 
+    dependencies {
+        classpath 'com.android.tools.build:gradle:3.3.0'
+    }
+}
 
-
+allprojects {
+    repositories {
+        google()
+        jcenter()
+    }
+}
 
 // BEGIN_EXCLUDE
 import com.example.android.samples.build.SampleGenPlugin
+
 apply plugin: SampleGenPlugin
 
 samplegen {
-  pathToBuild "../../../../../build"
-  pathToSamplesCommon "../../../common"
+    pathToBuild "../../../../../build"
+    pathToSamplesCommon "../../../common"
 }
 apply from: "../../../../../build/build.gradle"
 // END_EXCLUDE
diff --git a/ui/graphics/PdfRendererBasic/gradle.properties b/ui/graphics/PdfRendererBasic/gradle.properties
new file mode 100644
index 00000000..795e261a
--- /dev/null
+++ b/ui/graphics/PdfRendererBasic/gradle.properties
@@ -0,0 +1,14 @@
+# Project-wide Gradle settings.
+
+# Specifies the JVM arguments used for the daemon process.
+# The setting is particularly useful for tweaking memory settings.
+# Default value: -Xmx10248m -XX:MaxPermSize=256m
+org.gradle.jvmargs=-Xmx2048m -XX:MaxPermSize=512m -XX:+HeapDumpOnOutOfMemoryError -Dfile.encoding=UTF-8
+
+# When configured, Gradle will run in incubating parallel mode.
+# This option should only be used with decoupled projects. More details, visit
+# http://www.gradle.org/docs/current/userguide/multi_project_builds.html#sec:decoupled_projects
+org.gradle.parallel=true
+
+android.useAndroidX=true
+android.enableJetifier=true
diff --git a/ui/graphics/PdfRendererBasic/kotlinApp/Application/build.gradle b/ui/graphics/PdfRendererBasic/kotlinApp/Application/build.gradle
index 44d34d58..a1be48c4 100644
--- a/ui/graphics/PdfRendererBasic/kotlinApp/Application/build.gradle
+++ b/ui/graphics/PdfRendererBasic/kotlinApp/Application/build.gradle
@@ -1,35 +1,39 @@
 apply plugin: 'com.android.application'
 apply plugin: 'kotlin-android'
-apply plugin: 'kotlin-android-extensions'
 
 android {
-    compileSdkVersion rootProject.ext.compileSdkVersion
+    compileSdkVersion 28
+
     defaultConfig {
-        applicationId "com.example.android.pdfrendererbasic"
-        minSdkVersion rootProject.ext.minSdkVersion
-        targetSdkVersion rootProject.ext.targetSdkVersion
-        testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
+        applicationId 'com.example.android.pdfrendererbasic'
+        minSdkVersion 21
+        targetSdkVersion 28
         versionCode 1
-        versionName "1.0"
+        versionName '1.0'
+        testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
     }
-    buildTypes {
-        release {
-            minifyEnabled false
-            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
+
+    testOptions {
+        unitTests {
+            returnDefaultValues = true
+            includeAndroidResources = true
         }
     }
 }
 
 dependencies {
-    implementation "com.android.support:appcompat-v7:$rootProject.ext.supportLibVersion"
-    implementation "com.android.support:support-v4:$rootProject.ext.supportLibVersion"
-    implementation "org.jetbrains.kotlin:kotlin-stdlib:$rootProject.ext.kotlinVersion"
+    implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk7:$kotlin_version"
+    implementation 'org.jetbrains.kotlinx:kotlinx-coroutines-android:1.1.0'
+
+    implementation 'androidx.appcompat:appcompat:1.0.2'
+
+    def lifecycle_version = '2.0.0'
+    implementation "androidx.lifecycle:lifecycle-extensions:$lifecycle_version"
+    androidTestImplementation "androidx.arch.core:core-testing:$lifecycle_version"
 
-    // Testing dependencies
-    androidTestImplementation "com.android.support.test.espresso:espresso-contrib:$rootProject.ext.espressoVersion"
-    androidTestImplementation "com.android.support.test.espresso:espresso-core:$rootProject.ext.espressoVersion"
-    androidTestCompile "com.android.support:support-annotations:$rootProject.ext.supportLibVersion"
-    androidTestCompile "com.android.support.test:runner:$rootProject.ext.supportTestVersion"
-    androidTestCompile "com.android.support.test:rules:$rootProject.ext.supportTestVersion"
-    testImplementation "junit:junit:$rootProject.ext.junitVersion"
+    testImplementation 'com.google.truth:truth:0.42'
+    testImplementation 'androidx.test:core:1.1.0'
+    testImplementation 'androidx.test:runner:1.1.1'
+    androidTestImplementation 'androidx.test.ext:truth:1.1.0'
+    androidTestImplementation 'androidx.test.espresso:espresso-core:3.1.1'
 }
diff --git a/ui/graphics/PdfRendererBasic/kotlinApp/Application/src/androidTest/java/com/example/android/pdfrendererbasic/PdfRendererBasicFragmentTests.kt b/ui/graphics/PdfRendererBasic/kotlinApp/Application/src/androidTest/java/com/example/android/pdfrendererbasic/PdfRendererBasicFragmentTests.kt
deleted file mode 100644
index b2abc69b..00000000
--- a/ui/graphics/PdfRendererBasic/kotlinApp/Application/src/androidTest/java/com/example/android/pdfrendererbasic/PdfRendererBasicFragmentTests.kt
+++ /dev/null
@@ -1,125 +0,0 @@
-/*
- * Copyright (C) 2017 The Android Open Source Project
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *      http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-package com.example.android.pdfrendererbasic
-
-import android.content.pm.ActivityInfo.SCREEN_ORIENTATION_LANDSCAPE
-import android.content.pm.ActivityInfo.SCREEN_ORIENTATION_PORTRAIT
-import android.support.test.espresso.Espresso.onView
-import android.support.test.espresso.action.ViewActions.click
-import android.support.test.espresso.matcher.ViewMatchers.withId
-import android.support.test.rule.ActivityTestRule
-import android.support.test.runner.AndroidJUnit4
-import android.widget.Button
-import org.junit.Assert.assertEquals
-import org.junit.Assert.assertFalse
-import org.junit.Assert.assertTrue
-import org.junit.Before
-import org.junit.Rule
-import org.junit.Test
-import org.junit.runner.RunWith
-
-/**
- * Tests for PdfRendererBasic sample.
- */
-@RunWith(AndroidJUnit4::class)
-class PdfRendererBasicFragmentTests {
-
-    private lateinit var fragment: PdfRendererBasicFragment
-    private lateinit var btnPrevious: Button
-    private lateinit var btnNext: Button
-
-    @Rule @JvmField
-    val activityTestRule = ActivityTestRule(MainActivity::class.java)
-
-    @Before fun before() {
-        activityTestRule.activity.supportFragmentManager.beginTransaction()
-        fragment = activityTestRule.activity.supportFragmentManager
-                .findFragmentByTag(FRAGMENT_PDF_RENDERER_BASIC) as PdfRendererBasicFragment
-    }
-
-    @Test fun testActivityTitle() {
-        // The title of the activity should be "PdfRendererBasic (1/10)" at first
-        val expectedActivityTitle = activityTestRule.activity.getString(
-                R.string.app_name_with_index, 1, fragment.getPageCount())
-        assertEquals(expectedActivityTitle, activityTestRule.activity.title)
-    }
-
-    @Test fun testButtons_previousDisabledAtFirst() {
-        setUpButtons()
-        // Check that the previous button is disabled at first
-        assertFalse(btnPrevious.isEnabled)
-        // The next button should be enabled
-        assertTrue(btnNext.isEnabled)
-    }
-
-    @Test fun testButtons_bothEnabledInMiddle() {
-        setUpButtons()
-        turnPages(1)
-        // Two buttons should be both enabled
-        assertTrue(btnPrevious.isEnabled)
-        assertTrue(btnNext.isEnabled)
-    }
-
-    @Test fun testButtons_nextDisabledLastPage() {
-        setUpButtons()
-        val pageCount = fragment.getPageCount()
-        // Click till it reaches the last page
-        turnPages(pageCount - 1)
-        // Check the page count
-        val expectedActivityTitle = activityTestRule.activity.getString(
-                R.string.app_name_with_index, pageCount, pageCount)
-        assertEquals(expectedActivityTitle, activityTestRule.activity.title)
-        // The previous button should be enabled
-        assertTrue(btnPrevious.isEnabled)
-        // Check that the next button is disabled
-        assertFalse(btnNext.isEnabled)
-    }
-
-    @Test fun testOrientationChangePreserveState() {
-        activityTestRule.activity.requestedOrientation = SCREEN_ORIENTATION_PORTRAIT
-        setUpButtons()
-        turnPages(1)
-        val pageCount = fragment.getPageCount()
-        val expectedActivityTitle = activityTestRule.activity
-                .getString(R.string.app_name_with_index, 2, pageCount)
-        assertEquals(expectedActivityTitle, activityTestRule.activity.title)
-        activityTestRule.activity.requestedOrientation = SCREEN_ORIENTATION_LANDSCAPE
-        // Check that the title is the same after orientation change
-        assertEquals(expectedActivityTitle, activityTestRule.activity.title)
-    }
-
-    /**
-     * Prepares references to the buttons "Previous" and "Next".
-     */
-    private fun setUpButtons() {
-        val view = fragment.view ?: return
-        btnPrevious = view.findViewById(R.id.previous)
-        btnNext = view.findViewById(R.id.next)
-    }
-
-    /**
-     * Click the "Next" button to turn the pages.
-     *
-     * @param count The number of times to turn pages.
-     */
-    private fun turnPages(count: Int) {
-        for (i in 0 until count) {
-            onView(withId(R.id.next)).perform(click())
-        }
-    }
-
-}
diff --git a/ui/graphics/PdfRendererBasic/kotlinApp/Application/src/androidTest/java/com/example/android/pdfrendererbasic/PdfRendererBasicViewModelTest.kt b/ui/graphics/PdfRendererBasic/kotlinApp/Application/src/androidTest/java/com/example/android/pdfrendererbasic/PdfRendererBasicViewModelTest.kt
new file mode 100644
index 00000000..c2d7b26a
--- /dev/null
+++ b/ui/graphics/PdfRendererBasic/kotlinApp/Application/src/androidTest/java/com/example/android/pdfrendererbasic/PdfRendererBasicViewModelTest.kt
@@ -0,0 +1,50 @@
+/*
+ * Copyright (C) 2019 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.example.android.pdfrendererbasic
+
+import androidx.arch.core.executor.testing.InstantTaskExecutorRule
+import androidx.test.core.app.ApplicationProvider
+import androidx.test.runner.AndroidJUnit4
+import com.google.common.truth.Truth.assertThat
+import org.junit.Rule
+import org.junit.Test
+import org.junit.runner.RunWith
+
+@RunWith(AndroidJUnit4::class)
+class PdfRendererBasicViewModelTest {
+
+    @get:Rule
+    val instantTaskExecutorRule = InstantTaskExecutorRule()
+
+    private val viewModel = PdfRendererBasicViewModel(
+            ApplicationProvider.getApplicationContext(), true)
+
+    @Test
+    fun allPages() {
+        assertThat(viewModel).isNotNull()
+        assertThat(viewModel.pageInfo.value).isEqualTo(0 to 10)
+        assertThat(viewModel.previousEnabled.value).isFalse()
+        assertThat(viewModel.nextEnabled.value).isTrue()
+        assertThat(viewModel.pageBitmap.value).isNotNull()
+        repeat(9) { viewModel.showNext() }
+        assertThat(viewModel.pageInfo.value).isEqualTo(9 to 10)
+        assertThat(viewModel.previousEnabled.value).isTrue()
+        assertThat(viewModel.nextEnabled.value).isFalse()
+        assertThat(viewModel.pageBitmap.value).isNotNull()
+    }
+
+}
diff --git a/ui/graphics/PdfRendererBasic/kotlinApp/Application/src/main/AndroidManifest.xml b/ui/graphics/PdfRendererBasic/kotlinApp/Application/src/main/AndroidManifest.xml
index de585c9c..22500853 100644
--- a/ui/graphics/PdfRendererBasic/kotlinApp/Application/src/main/AndroidManifest.xml
+++ b/ui/graphics/PdfRendererBasic/kotlinApp/Application/src/main/AndroidManifest.xml
@@ -14,17 +14,21 @@
  See the License for the specific language governing permissions and
  limitations under the License.
 -->
-
-<manifest xmlns:android="http://schemas.android.com/apk/res/android"
+<manifest
+    xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:tools="http://schemas.android.com/tools"
     package="com.example.android.pdfrendererbasic">
 
-    <application android:allowBackup="false"
-        android:label="@string/app_name"
+    <application
+        android:allowBackup="false"
         android:icon="@mipmap/ic_launcher"
-        android:theme="@style/Theme.PdfRendererBasic">
+        android:label="@string/app_name"
+        android:theme="@style/Theme.PdfRendererBasic"
+        tools:ignore="GoogleAppIndexingWarning">
 
-        <activity android:name=".MainActivity"
-                  android:label="@string/app_name">
+        <activity
+            android:name=".MainActivity"
+            android:label="@string/app_name">
             <intent-filter>
                 <action android:name="android.intent.action.MAIN" />
                 <category android:name="android.intent.category.LAUNCHER" />
@@ -32,5 +36,4 @@
         </activity>
     </application>
 
-
 </manifest>
diff --git a/ui/graphics/PdfRendererBasic/kotlinApp/Application/src/main/java/com/example/android/pdfrendererbasic/MainActivity.kt b/ui/graphics/PdfRendererBasic/kotlinApp/Application/src/main/java/com/example/android/pdfrendererbasic/MainActivity.kt
index 1d253bd1..dd0ffc59 100644
--- a/ui/graphics/PdfRendererBasic/kotlinApp/Application/src/main/java/com/example/android/pdfrendererbasic/MainActivity.kt
+++ b/ui/graphics/PdfRendererBasic/kotlinApp/Application/src/main/java/com/example/android/pdfrendererbasic/MainActivity.kt
@@ -16,24 +16,27 @@
 
 package com.example.android.pdfrendererbasic
 
-import android.app.AlertDialog
+import android.app.Dialog
 import android.os.Bundle
-import android.support.v7.app.AppCompatActivity
 import android.view.Menu
 import android.view.MenuItem
-
-val FRAGMENT_PDF_RENDERER_BASIC = "pdf_renderer_basic"
+import androidx.appcompat.app.AlertDialog
+import androidx.appcompat.app.AppCompatActivity
+import androidx.fragment.app.DialogFragment
 
 class MainActivity : AppCompatActivity() {
 
+    companion object {
+        const val FRAGMENT_INFO = "info"
+    }
 
     override fun onCreate(savedInstanceState: Bundle?) {
         super.onCreate(savedInstanceState)
-        setContentView(R.layout.activity_main_real)
+        setContentView(R.layout.main_activity)
         if (savedInstanceState == null) {
             supportFragmentManager.beginTransaction()
-                    .add(R.id.container, PdfRendererBasicFragment(), FRAGMENT_PDF_RENDERER_BASIC)
-                    .commit()
+                    .replace(R.id.container, PdfRendererBasicFragment())
+                    .commitNow()
         }
     }
 
@@ -45,14 +48,20 @@ class MainActivity : AppCompatActivity() {
     override fun onOptionsItemSelected(item: MenuItem): Boolean {
         return when (item.itemId) {
             R.id.action_info -> {
-                AlertDialog.Builder(this)
-                        .setMessage(R.string.intro_message)
-                        .setPositiveButton(android.R.string.ok, null)
-                        .show()
+                InfoFragment().show(supportFragmentManager, FRAGMENT_INFO)
                 return true
             }
             else -> super.onOptionsItemSelected(item)
         }
     }
 
+    class InfoFragment : DialogFragment() {
+        override fun onCreateDialog(savedInstanceState: Bundle?): Dialog {
+            return AlertDialog.Builder(requireContext())
+                    .setMessage(R.string.intro_message)
+                    .setPositiveButton(android.R.string.ok, null)
+                    .show()
+        }
+    }
+
 }
diff --git a/ui/graphics/PdfRendererBasic/kotlinApp/Application/src/main/java/com/example/android/pdfrendererbasic/PdfRendererBasicFragment.kt b/ui/graphics/PdfRendererBasic/kotlinApp/Application/src/main/java/com/example/android/pdfrendererbasic/PdfRendererBasicFragment.kt
index 89e1cfd0..1ffc5817 100644
--- a/ui/graphics/PdfRendererBasic/kotlinApp/Application/src/main/java/com/example/android/pdfrendererbasic/PdfRendererBasicFragment.kt
+++ b/ui/graphics/PdfRendererBasic/kotlinApp/Application/src/main/java/com/example/android/pdfrendererbasic/PdfRendererBasicFragment.kt
@@ -16,222 +16,47 @@
 
 package com.example.android.pdfrendererbasic
 
-import android.content.Context
-import android.graphics.Bitmap
-import android.graphics.Bitmap.createBitmap
-import android.graphics.pdf.PdfRenderer
 import android.os.Bundle
-import android.os.ParcelFileDescriptor
-import android.support.v4.app.Fragment
-import android.util.Log
 import android.view.LayoutInflater
 import android.view.View
 import android.view.ViewGroup
 import android.widget.Button
 import android.widget.ImageView
-import java.io.File
-import java.io.FileOutputStream
-import java.io.IOException
+import androidx.fragment.app.Fragment
+import androidx.lifecycle.Observer
+import androidx.lifecycle.ViewModelProviders
 
 /**
  * This fragment has a big [ImageView] that shows PDF pages, and 2 [Button]s to move between pages.
- * We use a [PdfRenderer] to render PDF pages as [Bitmap]s.
  */
-class PdfRendererBasicFragment : Fragment(), View.OnClickListener {
+class PdfRendererBasicFragment : Fragment() {
 
-    /**
-     * The filename of the PDF.
-     */
-    private val FILENAME = "sample.pdf"
-
-    /**
-     * Key string for saving the state of current page index.
-     */
-    private val STATE_CURRENT_PAGE_INDEX = "current_page_index"
-
-    /**
-     * String for logging.
-     */
-    private val TAG = "PdfRendererBasicFragment"
-
-    /**
-     * The initial page index of the PDF.
-     */
-    private val INITIAL_PAGE_INDEX = 0
-
-    /**
-     * File descriptor of the PDF.
-     */
-    private lateinit var fileDescriptor: ParcelFileDescriptor
-
-    /**
-     * [PdfRenderer] to render the PDF.
-     */
-    private lateinit var pdfRenderer: PdfRenderer
-
-    /**
-     * Page that is currently shown on the screen.
-     */
-    private lateinit var currentPage: PdfRenderer.Page
-
-    /**
-     * [ImageView] that shows a PDF page as a [Bitmap].
-     */
-    private lateinit var imageView: ImageView
-
-    /**
-     * [Button] to move to the previous page.
-     */
-    private lateinit var btnPrevious: Button
-
-    /**
-     * [Button] to move to the next page.
-     */
-    private lateinit var btnNext: Button
-
-    /**
-     * PDF page index.
-     */
-    private var pageIndex: Int = INITIAL_PAGE_INDEX
-
-    override fun onCreateView(
-            inflater: LayoutInflater,
-            container: ViewGroup?,
-            savedInstanceState: Bundle?
-    ): View? {
-        return inflater.inflate(R.layout.fragment_pdf_renderer_basic, container, false)
+    override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?, savedInstanceState: Bundle?): View? {
+        return inflater.inflate(R.layout.pdf_renderer_basic_fragment, container, false)
     }
 
     override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
-        super.onViewCreated(view, savedInstanceState)
-        imageView = view.findViewById(R.id.image)
-        btnPrevious = view.findViewById<Button>(R.id.previous).also { it.setOnClickListener(this) }
-        btnNext = view.findViewById<Button>(R.id.next).also { it.setOnClickListener(this)}
-
-        // If there is a savedInstanceState (screen orientations, etc.), we restore the page index.
-        if (savedInstanceState != null) {
-            pageIndex = savedInstanceState.getInt(STATE_CURRENT_PAGE_INDEX, INITIAL_PAGE_INDEX)
-        } else {
-            pageIndex = INITIAL_PAGE_INDEX
-        }
-    }
-
-    override fun onStart() {
-        super.onStart()
-        try {
-            openRenderer(activity)
-            showPage(pageIndex)
-        } catch (e: IOException) {
-            Log.d(TAG, e.toString())
-        }
-    }
-
-    override fun onStop() {
-        try {
-            closeRenderer()
-        } catch (e: IOException) {
-            Log.d(TAG, e.toString())
-        }
-        super.onStop()
-    }
-
-    override fun onSaveInstanceState(outState: Bundle) {
-        outState.putInt(STATE_CURRENT_PAGE_INDEX, currentPage.index)
-        super.onSaveInstanceState(outState)
-    }
-
-    /**
-     * Sets up a [PdfRenderer] and related resources.
-     */
-    @Throws(IOException::class)
-    private fun openRenderer(context: Context?) {
-        if (context == null) return
-
-        // In this sample, we read a PDF from the assets directory.
-        val file = File(context.cacheDir, FILENAME)
-        if (!file.exists()) {
-            // Since PdfRenderer cannot handle the compressed asset file directly, we copy it into
-            // the cache directory.
-            val asset = context.assets.open(FILENAME)
-            val output = FileOutputStream(file)
-            val buffer = ByteArray(1024)
-            var size = asset.read(buffer)
-            while (size != -1) {
-                output.write(buffer, 0, size)
-                size = asset.read(buffer)
-            }
-            asset.close()
-            output.close()
-        }
-        fileDescriptor = ParcelFileDescriptor.open(file, ParcelFileDescriptor.MODE_READ_ONLY)
-        // This is the PdfRenderer we use to render the PDF.
-        pdfRenderer = PdfRenderer(fileDescriptor)
-        currentPage = pdfRenderer.openPage(pageIndex)
-    }
-
-    /**
-     * Closes the [PdfRenderer] and related resources.
-     *
-     * @throws IOException When the PDF file cannot be closed.
-     */
-    @Throws(IOException::class)
-    private fun closeRenderer() {
-        currentPage.close()
-        pdfRenderer.close()
-        fileDescriptor.close()
-    }
-
-    /**
-     * Shows the specified page of PDF to the screen.
-     *
-     * @param index The page index.
-     */
-    private fun showPage(index: Int) {
-        if (pdfRenderer.pageCount <= index) return
-
-        // Make sure to close the current page before opening another one.
-        currentPage.close()
-        // Use `openPage` to open a specific page in PDF.
-        currentPage = pdfRenderer.openPage(index)
-        // Important: the destination bitmap must be ARGB (not RGB).
-        val bitmap = createBitmap(currentPage.width, currentPage.height, Bitmap.Config.ARGB_8888)
-        // Here, we render the page onto the Bitmap.
-        // To render a portion of the page, use the second and third parameter. Pass nulls to get
-        // the default result.
-        // Pass either RENDER_MODE_FOR_DISPLAY or RENDER_MODE_FOR_PRINT for the last parameter.
-        currentPage.render(bitmap, null, null, PdfRenderer.Page.RENDER_MODE_FOR_DISPLAY)
-        // We are ready to show the Bitmap to user.
-        imageView.setImageBitmap(bitmap)
-        updateUi()
-    }
-
-    /**
-     * Updates the state of 2 control buttons in response to the current page index.
-     */
-    private fun updateUi() {
-        val index = currentPage.index
-        val pageCount = pdfRenderer.pageCount
-        btnPrevious.isEnabled = (0 != index)
-        btnNext.isEnabled = (index + 1 < pageCount)
-        activity?.title = getString(R.string.app_name_with_index, index + 1, pageCount)
-    }
-
-    /**
-     * Returns the page count of of the PDF.
-     */
-    fun getPageCount() = pdfRenderer.pageCount
-
-    override fun onClick(view: View) {
-        when (view.id) {
-            R.id.previous -> {
-                // Move to the previous page/
-                showPage(currentPage.index - 1)
-            }
-            R.id.next -> {
-                // Move to the next page.
-                showPage(currentPage.index + 1)
-            }
-        }
+        // View references.
+        val image: ImageView = view.findViewById(R.id.image)
+        val buttonPrevious: Button = view.findViewById(R.id.previous)
+        val buttonNext: Button = view.findViewById(R.id.next)
+
+        // Bind data.
+        val viewModel = ViewModelProviders.of(this).get(PdfRendererBasicViewModel::class.java)
+        viewModel.pageInfo.observe(viewLifecycleOwner, Observer { (index, count) ->
+            activity?.title = getString(R.string.app_name_with_index, index + 1, count)
+        })
+        viewModel.pageBitmap.observe(viewLifecycleOwner, Observer { image.setImageBitmap(it) })
+        viewModel.previousEnabled.observe(viewLifecycleOwner, Observer {
+            buttonPrevious.isEnabled = it
+        })
+        viewModel.nextEnabled.observe(viewLifecycleOwner, Observer {
+            buttonNext.isEnabled = it
+        })
+
+        // Bind events.
+        buttonPrevious.setOnClickListener { viewModel.showPrevious() }
+        buttonNext.setOnClickListener { viewModel.showNext() }
     }
 
 }
diff --git a/ui/graphics/PdfRendererBasic/kotlinApp/Application/src/main/java/com/example/android/pdfrendererbasic/PdfRendererBasicViewModel.kt b/ui/graphics/PdfRendererBasic/kotlinApp/Application/src/main/java/com/example/android/pdfrendererbasic/PdfRendererBasicViewModel.kt
new file mode 100644
index 00000000..6324cce3
--- /dev/null
+++ b/ui/graphics/PdfRendererBasic/kotlinApp/Application/src/main/java/com/example/android/pdfrendererbasic/PdfRendererBasicViewModel.kt
@@ -0,0 +1,158 @@
+/*
+ * Copyright (C) 2019 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.example.android.pdfrendererbasic
+
+import android.app.Application
+import android.graphics.Bitmap
+import android.graphics.pdf.PdfRenderer
+import android.os.ParcelFileDescriptor
+import androidx.lifecycle.AndroidViewModel
+import androidx.lifecycle.LiveData
+import androidx.lifecycle.MutableLiveData
+import kotlinx.coroutines.CoroutineScope
+import kotlinx.coroutines.Job
+import kotlinx.coroutines.asCoroutineDispatcher
+import kotlinx.coroutines.launch
+import java.io.File
+import java.util.concurrent.Executor
+import java.util.concurrent.Executors
+
+class PdfRendererBasicViewModel @JvmOverloads constructor(
+        application: Application,
+        useInstantExecutor: Boolean = false
+) : AndroidViewModel(application) {
+
+    companion object {
+        const val FILENAME = "sample.pdf"
+    }
+
+    private val job = Job()
+    private val executor = if (useInstantExecutor) {
+        Executor { it.run() }
+    } else {
+        Executors.newSingleThreadExecutor()
+    }
+    private val scope = CoroutineScope(executor.asCoroutineDispatcher() + job)
+
+    private var fileDescriptor: ParcelFileDescriptor? = null
+    private var pdfRenderer: PdfRenderer? = null
+    private var currentPage: PdfRenderer.Page? = null
+    private var cleared = false
+
+    private val _pageBitmap = MutableLiveData<Bitmap>()
+    val pageBitmap: LiveData<Bitmap>
+        get() = _pageBitmap
+
+    private val _previousEnabled = MutableLiveData<Boolean>()
+    val previousEnabled: LiveData<Boolean>
+        get() = _previousEnabled
+
+    private val _nextEnabled = MutableLiveData<Boolean>()
+    val nextEnabled: LiveData<Boolean>
+        get() = _nextEnabled
+
+    private val _pageInfo = MutableLiveData<Pair<Int, Int>>()
+    val pageInfo: LiveData<Pair<Int, Int>>
+        get() = _pageInfo
+
+    init {
+        scope.launch {
+            openPdfRenderer()
+            showPage(0)
+            if (cleared) {
+                closePdfRenderer()
+            }
+        }
+    }
+
+    override fun onCleared() {
+        super.onCleared()
+        scope.launch {
+            closePdfRenderer()
+            cleared = true
+            job.cancel()
+        }
+    }
+
+    fun showPrevious() {
+        scope.launch {
+            currentPage?.let { page ->
+                if (page.index > 0) {
+                    showPage(page.index - 1)
+                }
+            }
+        }
+    }
+
+    fun showNext() {
+        scope.launch {
+            pdfRenderer?.let { renderer ->
+                currentPage?.let { page ->
+                    if (page.index + 1 < renderer.pageCount) {
+                        showPage(page.index + 1)
+                    }
+                }
+            }
+        }
+    }
+
+    private fun openPdfRenderer() {
+        val application = getApplication<Application>()
+        val file = File(application.cacheDir, FILENAME)
+        if (!file.exists()) {
+            application.assets.open(FILENAME).use { asset ->
+                file.writeBytes(asset.readBytes())
+            }
+        }
+        fileDescriptor = ParcelFileDescriptor.open(file, ParcelFileDescriptor.MODE_READ_ONLY).also {
+            pdfRenderer = PdfRenderer(it)
+        }
+    }
+
+    private fun showPage(index: Int) {
+        // Make sure to close the current page before opening another one.
+        currentPage?.let { page ->
+            currentPage = null
+            page.close()
+        }
+        pdfRenderer?.let { renderer ->
+            // Use `openPage` to open a specific page in PDF.
+            val page = renderer.openPage(index).also {
+                currentPage = it
+            }
+            // Important: the destination bitmap must be ARGB (not RGB).
+            val bitmap = Bitmap.createBitmap(page.width, page.height, Bitmap.Config.ARGB_8888)
+            // Here, we render the page onto the Bitmap.
+            // To render a portion of the page, use the second and third parameter. Pass nulls to get
+            // the default result.
+            // Pass either RENDER_MODE_FOR_DISPLAY or RENDER_MODE_FOR_PRINT for the last parameter.
+            page.render(bitmap, null, null, PdfRenderer.Page.RENDER_MODE_FOR_DISPLAY)
+            _pageBitmap.postValue(bitmap)
+            val count = renderer.pageCount
+            _pageInfo.postValue(index to count)
+            _previousEnabled.postValue(index > 0)
+            _nextEnabled.postValue(index + 1 < count)
+        }
+    }
+
+    private fun closePdfRenderer() {
+        currentPage?.close()
+        pdfRenderer?.close()
+        fileDescriptor?.close()
+    }
+
+}
diff --git a/ui/graphics/PdfRendererBasic/kotlinApp/Application/src/main/res/layout/activity_main_real.xml b/ui/graphics/PdfRendererBasic/kotlinApp/Application/src/main/res/layout/activity_main_real.xml
deleted file mode 100644
index 5d130ff5..00000000
--- a/ui/graphics/PdfRendererBasic/kotlinApp/Application/src/main/res/layout/activity_main_real.xml
+++ /dev/null
@@ -1,23 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<!--
- Copyright 2017 The Android Open Source Project
-
- Licensed under the Apache License, Version 2.0 (the "License");
- you may not use this file except in compliance with the License.
- You may obtain a copy of the License at
-
-     http://www.apache.org/licenses/LICENSE-2.0
-
- Unless required by applicable law or agreed to in writing, software
- distributed under the License is distributed on an "AS IS" BASIS,
- WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- See the License for the specific language governing permissions and
- limitations under the License.
--->
-<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
-    xmlns:tools="http://schemas.android.com/tools"
-    android:id="@+id/container"
-    android:layout_width="match_parent"
-    android:layout_height="match_parent"
-    tools:context=".MainActivity"
-    tools:ignore="MergeRootFrame" />
diff --git a/ui/graphics/PdfRendererBasic/kotlinApp/Application/src/main/res/layout/main_activity.xml b/ui/graphics/PdfRendererBasic/kotlinApp/Application/src/main/res/layout/main_activity.xml
new file mode 100644
index 00000000..a613a72c
--- /dev/null
+++ b/ui/graphics/PdfRendererBasic/kotlinApp/Application/src/main/res/layout/main_activity.xml
@@ -0,0 +1,23 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!--
+  Copyright (C) 2017 The Android Open Source Project
+
+  Licensed under the Apache License, Version 2.0 (the "License");
+  you may not use this file except in compliance with the License.
+  You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+  Unless required by applicable law or agreed to in writing, software
+  distributed under the License is distributed on an "AS IS" BASIS,
+  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+  See the License for the specific language governing permissions and
+  limitations under the License.
+-->
+<FrameLayout
+    xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:tools="http://schemas.android.com/tools"
+    android:id="@+id/container"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent"
+    tools:context=".MainActivity" />
diff --git a/ui/graphics/PdfRendererBasic/kotlinApp/Application/src/main/res/layout/fragment_pdf_renderer_basic.xml b/ui/graphics/PdfRendererBasic/kotlinApp/Application/src/main/res/layout/pdf_renderer_basic_fragment.xml
index aa8a9e1a..719502ed 100644
--- a/ui/graphics/PdfRendererBasic/kotlinApp/Application/src/main/res/layout/fragment_pdf_renderer_basic.xml
+++ b/ui/graphics/PdfRendererBasic/kotlinApp/Application/src/main/res/layout/pdf_renderer_basic_fragment.xml
@@ -1,18 +1,18 @@
-<?xml version="1.0" encoding="UTF-8"?>
+<?xml version="1.0" encoding="utf-8"?>
 <!--
- Copyright 2017 The Android Open Source Project
+  Copyright (C) 2017 The Android Open Source Project
 
- Licensed under the Apache License, Version 2.0 (the "License");
- you may not use this file except in compliance with the License.
- You may obtain a copy of the License at
+  Licensed under the Apache License, Version 2.0 (the "License");
+  you may not use this file except in compliance with the License.
+  You may obtain a copy of the License at
 
-     http://www.apache.org/licenses/LICENSE-2.0
+       http://www.apache.org/licenses/LICENSE-2.0
 
- Unless required by applicable law or agreed to in writing, software
- distributed under the License is distributed on an "AS IS" BASIS,
- WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- See the License for the specific language governing permissions and
- limitations under the License.
+  Unless required by applicable law or agreed to in writing, software
+  distributed under the License is distributed on an "AS IS" BASIS,
+  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+  See the License for the specific language governing permissions and
+  limitations under the License.
 -->
 <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
     xmlns:tools="http://schemas.android.com/tools"
@@ -52,7 +52,6 @@
             android:layout_height="wrap_content"
             android:layout_weight="1"
             android:text="@string/next" />
-
     </LinearLayout>
 
 </LinearLayout>
diff --git a/ui/graphics/PdfRendererBasic/kotlinApp/Application/src/main/res/values/strings.xml b/ui/graphics/PdfRendererBasic/kotlinApp/Application/src/main/res/values/strings.xml
index 55f04f91..04968e4d 100644
--- a/ui/graphics/PdfRendererBasic/kotlinApp/Application/src/main/res/values/strings.xml
+++ b/ui/graphics/PdfRendererBasic/kotlinApp/Application/src/main/res/values/strings.xml
@@ -15,19 +15,10 @@
  limitations under the License.
 -->
 <resources>
-
     <string name="app_name">PdfRendererBasic</string>
     <string name="app_name_with_index">PdfRendererBasic (%1$d/%2$d)</string>
     <string name="info">Info</string>
     <string name="previous">Previous</string>
     <string name="next">Next</string>
-    <string name="intro_message">
-        <![CDATA[
-
-
-            This sample demonstrates how to use PdfRenderer to display PDF documents on the screen.
-
-
-        ]]>
-    </string>
+    <string name="intro_message">This sample demonstrates how to use PdfRenderer to display PDF documents on the screen</string>
 </resources>
diff --git a/ui/graphics/PdfRendererBasic/kotlinApp/build.gradle b/ui/graphics/PdfRendererBasic/kotlinApp/build.gradle
index daa90118..4086415a 100644
--- a/ui/graphics/PdfRendererBasic/kotlinApp/build.gradle
+++ b/ui/graphics/PdfRendererBasic/kotlinApp/build.gradle
@@ -1,22 +1,13 @@
 buildscript {
-    ext {
-        compileSdkVersion = 27
-        minSdkVersion = 24
-        targetSdkVersion = 27
-
-        espressoVersion = '3.0.1'
-        junitVersion = '4.12'
-        kotlinVersion = '1.3.11'
-        supportLibVersion = '27.0.2'
-        supportTestVersion = '1.0.1'
-    }
+    ext.kotlin_version = '1.3.11'
     repositories {
         google()
         jcenter()
     }
+
     dependencies {
         classpath 'com.android.tools.build:gradle:3.3.0'
-        classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlinVersion"
+        classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
     }
 }
 
@@ -26,7 +17,3 @@ allprojects {
         jcenter()
     }
 }
-
-task clean(type: Delete) {
-    delete rootProject.buildDir
-}
diff --git a/ui/graphics/PdfRendererBasic/template-params.xml b/ui/graphics/PdfRendererBasic/template-params.xml
index 81ea8268..3d79c17e 100644
--- a/ui/graphics/PdfRendererBasic/template-params.xml
+++ b/ui/graphics/PdfRendererBasic/template-params.xml
@@ -33,7 +33,8 @@
         </intro>
     </strings>
 
-    <template src="base"/>
+    <template src="base-build"/>
+    <androidX>true</androidX>
 
     <metadata>
         <status>PUBLISHED</status>