Add IllustrationVideoView to setup wizard library

- Upstreamed setup wizard's IllustrationVideoView to SuwLib
- Modified the view to automatically listen to window focus changes
  to play and pause the video
- The view will now release the MediaPlayer as well in
  onSurfaceTextureDestroyed
- Added checkstyle_suppression XML so it will ignore the
  "__constructor__" magic method name from the style check.

Bug: 36584499
Test: ./gradlew connectedAndroidTest test
Change-Id: Id045467d5d544a5f54464a0c938d3d56e758e455

2 files changed, 234 insertions, 0 deletions

diff --git a/library/main/res/values/attrs.xml b/library/main/res/values/attrs.xml
index ec6489e..36d5fb7 100644
--- a/library/main/res/values/attrs.xml
+++ b/library/main/res/values/attrs.xml
@@ -93,6 +93,10 @@
         <attr name="suwHeader" />
     </declare-styleable>
 
+    <declare-styleable name="SuwIllustrationVideoView">
+        <attr name="suwVideo" format="reference" />
+    </declare-styleable>
+
     <declare-styleable name="SuwGlifLayout">
         <attr name="suwBackgroundPatterned" format="boolean" />
         <attr name="suwBackgroundBaseColor" format="color" />
diff --git a/library/main/src/com/android/setupwizardlib/view/IllustrationVideoView.java b/library/main/src/com/android/setupwizardlib/view/IllustrationVideoView.java
new file mode 100644
index 0000000..989f3e6
--- /dev/null
+++ b/library/main/src/com/android/setupwizardlib/view/IllustrationVideoView.java
@@ -0,0 +1,230 @@
+/*
+ * 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.android.setupwizardlib.view;
+
+import android.annotation.TargetApi;
+import android.content.Context;
+import android.content.res.TypedArray;
+import android.graphics.SurfaceTexture;
+import android.graphics.drawable.Animatable;
+import android.media.MediaPlayer;
+import android.os.Build.VERSION_CODES;
+import android.support.annotation.RawRes;
+import android.support.annotation.VisibleForTesting;
+import android.util.AttributeSet;
+import android.view.Surface;
+import android.view.TextureView;
+import android.view.View;
+
+import com.android.setupwizardlib.R;
+
+/**
+ * A view for displaying videos in a continuous loop (without audio). This is typically used for
+ * animated illustrations.
+ *
+ * <p>The video can be specified using {@code app:suwVideo}, specifying the raw resource to the mp4
+ * video. Optionally, {@code app:suwLoopStartMs} can be used to specify which part of the video it
+ * should loop back to
+ *
+ * <p>For optimal file size, use avconv or other video compression tool to remove the unused audio
+ * track and reduce the size of your video asset:
+ *     avconv -i [input file] -vcodec h264 -crf 20 -an [output_file]
+ */
+@TargetApi(VERSION_CODES.ICE_CREAM_SANDWICH)
+public class IllustrationVideoView extends TextureView implements Animatable,
+        TextureView.SurfaceTextureListener,
+        MediaPlayer.OnPreparedListener,
+        MediaPlayer.OnSeekCompleteListener,
+        MediaPlayer.OnInfoListener {
+
+    protected float mAspectRatio = 1.0f; // initial guess until we know
+
+    @VisibleForTesting MediaPlayer mMediaPlayer;
+
+    private @RawRes int mVideoResId = 0;
+
+    @VisibleForTesting Surface mSurface;
+
+    public IllustrationVideoView(Context context, AttributeSet attrs) {
+        super(context, attrs);
+        final TypedArray a = context.obtainStyledAttributes(attrs,
+                R.styleable.SuwIllustrationVideoView);
+        mVideoResId = a.getResourceId(R.styleable.SuwIllustrationVideoView_suwVideo, 0);
+        a.recycle();
+
+        setSurfaceTextureListener(this);
+    }
+
+    @Override
+    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
+        int width = MeasureSpec.getSize(widthMeasureSpec);
+        int height = MeasureSpec.getSize(heightMeasureSpec);
+
+        if (height < width * mAspectRatio) {
+            // Height constraint is tighter. Need to scale down the width to fit aspect ratio.
+            width = (int) (height / mAspectRatio);
+        } else {
+            // Width constraint is tighter. Need to scale down the height to fit aspect ratio.
+            height = (int) (width * mAspectRatio);
+        }
+
+        super.onMeasure(
+                MeasureSpec.makeMeasureSpec(width, MeasureSpec.EXACTLY),
+                MeasureSpec.makeMeasureSpec(height, MeasureSpec.EXACTLY));
+    }
+
+    /**
+     * Set the video to be played by this view.
+     *
+     * @param resId Resource ID of the video, typically an MP4 under res/raw.
+     */
+    public void setVideoResource(@RawRes int resId) {
+        if (resId != mVideoResId) {
+            mVideoResId = resId;
+            createMediaPlayer();
+        }
+    }
+
+    @Override
+    public void onWindowFocusChanged(boolean hasWindowFocus) {
+        super.onWindowFocusChanged(hasWindowFocus);
+        if (hasWindowFocus) {
+            start();
+        } else {
+            stop();
+        }
+    }
+
+    /**
+     * Creates a media player for the current URI. The media player will be started immediately if
+     * the view's window is visible. If there is an existing media player, it will be released.
+     */
+    private void createMediaPlayer() {
+        if (mMediaPlayer != null) {
+            mMediaPlayer.release();
+        }
+        if (mSurface == null || mVideoResId == 0) {
+            return;
+        }
+
+        mMediaPlayer = MediaPlayer.create(getContext(), mVideoResId);
+
+        mMediaPlayer.setSurface(mSurface);
+        mMediaPlayer.setOnPreparedListener(this);
+        mMediaPlayer.setOnSeekCompleteListener(this);
+        mMediaPlayer.setOnInfoListener(this);
+
+        float aspectRatio = (float) mMediaPlayer.getVideoHeight() / mMediaPlayer.getVideoWidth();
+        if (mAspectRatio != aspectRatio) {
+            mAspectRatio = aspectRatio;
+            requestLayout();
+        }
+        if (getWindowVisibility() == View.VISIBLE) {
+            start();
+        }
+    }
+
+    /**
+     * Whether the media player should play the video in a continuous loop. The default value is
+     * true.
+     */
+    protected boolean shouldLoop() {
+        return true;
+    }
+
+    /**
+     * Release any resources used by this view. This is automatically called in
+     * onSurfaceTextureDestroyed so in most cases you don't have to call this.
+     */
+    public void release() {
+        if (mMediaPlayer != null) {
+            mMediaPlayer.stop();
+            mMediaPlayer.release();
+            mMediaPlayer = null;
+        }
+        if (mSurface != null) {
+            mSurface.release();
+            mSurface = null;
+        }
+    }
+
+    /* SurfaceTextureListener methods */
+
+    @Override
+    public void onSurfaceTextureAvailable(SurfaceTexture surfaceTexture, int width, int height) {
+        // Keep the view hidden until video starts
+        setVisibility(View.INVISIBLE);
+        mSurface = new Surface(surfaceTexture);
+        createMediaPlayer();
+    }
+
+    @Override
+    public void onSurfaceTextureSizeChanged(SurfaceTexture surfaceTexture, int width, int height) {
+    }
+
+    @Override
+    public boolean onSurfaceTextureDestroyed(SurfaceTexture surfaceTexture) {
+        release();
+        return true;
+    }
+
+    @Override
+    public void onSurfaceTextureUpdated(SurfaceTexture surfaceTexture) {
+    }
+
+    /* Animatable methods */
+
+    @Override
+    public void start() {
+        if (mMediaPlayer != null && !mMediaPlayer.isPlaying()) {
+            mMediaPlayer.start();
+        }
+    }
+
+    @Override
+    public void stop() {
+        if (mMediaPlayer != null) {
+            mMediaPlayer.pause();
+        }
+    }
+
+    @Override
+    public boolean isRunning() {
+        return mMediaPlayer != null && mMediaPlayer.isPlaying();
+    }
+
+    /* MediaPlayer callbacks */
+
+    @Override
+    public boolean onInfo(MediaPlayer mp, int what, int extra) {
+        if (what == MediaPlayer.MEDIA_INFO_VIDEO_RENDERING_START) {
+            // Video available, show view now
+            setVisibility(View.VISIBLE);
+        }
+        return false;
+    }
+
+    @Override
+    public void onPrepared(MediaPlayer mp) {
+        mp.setLooping(shouldLoop());
+    }
+
+    @Override
+    public void onSeekComplete(MediaPlayer mp) {
+        mp.start();
+    }
+}