Convert @ContentView to constructor annotation

As layout IDs are non-final in library modules
(and in the future, app modules), change
@ContentView to only be a marker annotation for
a constructor which developers can call with
a specific layout ID.

Fixes: 128352521
Fixes: 127531658
Test: updated tests
Change-Id: I15e2edee8cbd68180991f89fbc3b04e12c961ede

25 files changed, 160 insertions, 114 deletions

diff --git a/activity/api/1.0.0-alpha06.txt b/activity/api/1.0.0-alpha06.txt
index c46e0cdedea..16e509e06b1 100644
--- a/activity/api/1.0.0-alpha06.txt
+++ b/activity/api/1.0.0-alpha06.txt
@@ -3,6 +3,7 @@ package androidx.activity {
 
   public class ComponentActivity extends androidx.core.app.ComponentActivity implements androidx.lifecycle.LifecycleOwner androidx.savedstate.SavedStateRegistryOwner androidx.lifecycle.ViewModelStoreOwner {
     ctor public ComponentActivity();
+    ctor @ContentView public ComponentActivity(@LayoutRes int);
     method @Deprecated public void addOnBackPressedCallback(androidx.activity.OnBackPressedCallback);
     method @Deprecated public void addOnBackPressedCallback(androidx.lifecycle.LifecycleOwner, androidx.activity.OnBackPressedCallback);
     method @Deprecated public Object? getLastCustomNonConfigurationInstance();
diff --git a/activity/api/current.txt b/activity/api/current.txt
index c46e0cdedea..16e509e06b1 100644
--- a/activity/api/current.txt
+++ b/activity/api/current.txt
@@ -3,6 +3,7 @@ package androidx.activity {
 
   public class ComponentActivity extends androidx.core.app.ComponentActivity implements androidx.lifecycle.LifecycleOwner androidx.savedstate.SavedStateRegistryOwner androidx.lifecycle.ViewModelStoreOwner {
     ctor public ComponentActivity();
+    ctor @ContentView public ComponentActivity(@LayoutRes int);
     method @Deprecated public void addOnBackPressedCallback(androidx.activity.OnBackPressedCallback);
     method @Deprecated public void addOnBackPressedCallback(androidx.lifecycle.LifecycleOwner, androidx.activity.OnBackPressedCallback);
     method @Deprecated public Object? getLastCustomNonConfigurationInstance();
diff --git a/activity/src/androidTest/java/androidx/activity/ContentViewTest.kt b/activity/src/androidTest/java/androidx/activity/ContentViewTest.kt
index be432311bdd..eff215cfa2b 100644
--- a/activity/src/androidTest/java/androidx/activity/ContentViewTest.kt
+++ b/activity/src/androidTest/java/androidx/activity/ContentViewTest.kt
@@ -18,7 +18,6 @@ package androidx.activity
 
 import android.widget.TextView
 import androidx.activity.test.R
-import androidx.annotation.ContentView
 import androidx.test.ext.junit.runners.AndroidJUnit4
 import androidx.test.filters.MediumTest
 import androidx.test.rule.ActivityTestRule
@@ -43,5 +42,4 @@ class ContentViewTest {
     }
 }
 
-@ContentView(R.layout.activity_inflates_res)
-class ContentViewActivity : ComponentActivity()
+class ContentViewActivity : ComponentActivity(R.layout.activity_inflates_res)
diff --git a/activity/src/main/java/androidx/activity/ComponentActivity.java b/activity/src/main/java/androidx/activity/ComponentActivity.java
index 1619920c1d3..2a3e3e9d453 100644
--- a/activity/src/main/java/androidx/activity/ComponentActivity.java
+++ b/activity/src/main/java/androidx/activity/ComponentActivity.java
@@ -25,6 +25,7 @@ import android.view.Window;
 
 import androidx.annotation.CallSuper;
 import androidx.annotation.ContentView;
+import androidx.annotation.LayoutRes;
 import androidx.annotation.NonNull;
 import androidx.annotation.Nullable;
 import androidx.arch.core.util.Cancellable;
@@ -39,7 +40,6 @@ import androidx.savedstate.SavedStateRegistry;
 import androidx.savedstate.SavedStateRegistryController;
 import androidx.savedstate.SavedStateRegistryOwner;
 
-import java.util.HashMap;
 import java.util.WeakHashMap;
 
 /**
@@ -73,9 +73,14 @@ public class ComponentActivity extends androidx.core.app.ComponentActivity imple
     private final WeakHashMap<OnBackPressedCallback, Cancellable>
             mOnBackPressedCallbackCancellables = new WeakHashMap<>();
 
-    // Cache the ContentView layoutIds for Activities.
-    private static final HashMap<Class, Integer> sAnnotationIds = new HashMap<>();
+    @LayoutRes
+    private int mContentLayoutId;
 
+    /**
+     * Default constructor for ComponentActivity. All Activities must have a default constructor
+     * for API 27 and lower devices or when using the default
+     * {@link android.app.AppComponentFactory}.
+     */
     public ComponentActivity() {
         Lifecycle lifecycle = getLifecycle();
         //noinspection ConstantConditions
@@ -116,6 +121,22 @@ public class ComponentActivity extends androidx.core.app.ComponentActivity imple
     }
 
     /**
+     * Alternate constructor that can be used to provide a default layout
+     * that will be inflated as part of <code>super.onCreate(savedInstanceState)</code>.
+     *
+     * <p>This should generally be called from your constructor that takes no parameters,
+     * as is required for API 27 and lower or when using the default
+     * {@link android.app.AppComponentFactory}.
+     *
+     * @see #ComponentActivity()
+     */
+    @ContentView
+    public ComponentActivity(@LayoutRes int contentLayoutId) {
+        this();
+        mContentLayoutId = contentLayoutId;
+    }
+
+    /**
      * {@inheritDoc}
      *
      * If your ComponentActivity is annotated with {@link ContentView}, this will
@@ -126,18 +147,8 @@ public class ComponentActivity extends androidx.core.app.ComponentActivity imple
         super.onCreate(savedInstanceState);
         mSavedStateRegistryController.performRestore(savedInstanceState);
         ReportFragment.injectIfNeededIn(this);
-        Class<? extends ComponentActivity> clazz = getClass();
-        if (!sAnnotationIds.containsKey(clazz)) {
-            ContentView annotation = clazz.getAnnotation(ContentView.class);
-            if (annotation != null) {
-                sAnnotationIds.put(clazz, annotation.value());
-            } else {
-                sAnnotationIds.put(clazz, null);
-            }
-        }
-        Integer layoutId = sAnnotationIds.get(clazz);
-        if (layoutId != null && layoutId != 0) {
-            setContentView(layoutId);
+        if (mContentLayoutId != 0) {
+            setContentView(mContentLayoutId);
         }
     }
 
diff --git a/annotations/api/1.1.0-beta01.txt b/annotations/api/1.1.0-beta01.txt
index 491ffea2f98..7e260ad643c 100644
--- a/annotations/api/1.1.0-beta01.txt
+++ b/annotations/api/1.1.0-beta01.txt
@@ -41,8 +41,7 @@ package androidx.annotation {
   @java.lang.annotation.Documented @java.lang.annotation.Retention(java.lang.annotation.RetentionPolicy.CLASS) @java.lang.annotation.Target({java.lang.annotation.ElementType.METHOD, java.lang.annotation.ElementType.PARAMETER, java.lang.annotation.ElementType.FIELD, java.lang.annotation.ElementType.LOCAL_VARIABLE}) public @interface ColorRes {
   }
 
-  @java.lang.annotation.Inherited @java.lang.annotation.Retention(java.lang.annotation.RetentionPolicy.RUNTIME) @java.lang.annotation.Target({java.lang.annotation.ElementType.TYPE}) public @interface ContentView {
-    method @LayoutRes public abstract int value();
+  @java.lang.annotation.Retention(java.lang.annotation.RetentionPolicy.CLASS) @java.lang.annotation.Target({java.lang.annotation.ElementType.CONSTRUCTOR}) public @interface ContentView {
   }
 
   @java.lang.annotation.Documented @java.lang.annotation.Retention(java.lang.annotation.RetentionPolicy.CLASS) @java.lang.annotation.Target({java.lang.annotation.ElementType.METHOD, java.lang.annotation.ElementType.PARAMETER, java.lang.annotation.ElementType.FIELD, java.lang.annotation.ElementType.LOCAL_VARIABLE}) public @interface DimenRes {
diff --git a/annotations/api/current.txt b/annotations/api/current.txt
index 491ffea2f98..7e260ad643c 100644
--- a/annotations/api/current.txt
+++ b/annotations/api/current.txt
@@ -41,8 +41,7 @@ package androidx.annotation {
   @java.lang.annotation.Documented @java.lang.annotation.Retention(java.lang.annotation.RetentionPolicy.CLASS) @java.lang.annotation.Target({java.lang.annotation.ElementType.METHOD, java.lang.annotation.ElementType.PARAMETER, java.lang.annotation.ElementType.FIELD, java.lang.annotation.ElementType.LOCAL_VARIABLE}) public @interface ColorRes {
   }
 
-  @java.lang.annotation.Inherited @java.lang.annotation.Retention(java.lang.annotation.RetentionPolicy.RUNTIME) @java.lang.annotation.Target({java.lang.annotation.ElementType.TYPE}) public @interface ContentView {
-    method @LayoutRes public abstract int value();
+  @java.lang.annotation.Retention(java.lang.annotation.RetentionPolicy.CLASS) @java.lang.annotation.Target({java.lang.annotation.ElementType.CONSTRUCTOR}) public @interface ContentView {
   }
 
   @java.lang.annotation.Documented @java.lang.annotation.Retention(java.lang.annotation.RetentionPolicy.CLASS) @java.lang.annotation.Target({java.lang.annotation.ElementType.METHOD, java.lang.annotation.ElementType.PARAMETER, java.lang.annotation.ElementType.FIELD, java.lang.annotation.ElementType.LOCAL_VARIABLE}) public @interface DimenRes {
diff --git a/annotations/src/main/java/androidx/annotation/ContentView.java b/annotations/src/main/java/androidx/annotation/ContentView.java
index eee0d2f63bf..f2f098dea4a 100644
--- a/annotations/src/main/java/androidx/annotation/ContentView.java
+++ b/annotations/src/main/java/androidx/annotation/ContentView.java
@@ -16,31 +16,31 @@
 
 package androidx.annotation;
 
-import static java.lang.annotation.ElementType.TYPE;
-import static java.lang.annotation.RetentionPolicy.RUNTIME;
+import static java.lang.annotation.ElementType.CONSTRUCTOR;
+import static java.lang.annotation.RetentionPolicy.CLASS;
 
-import java.lang.annotation.Inherited;
 import java.lang.annotation.Retention;
 import java.lang.annotation.Target;
 
 /**
- * Annotation that can be attached to a component such as an
- * androidx.activity.ComponentActivity or {@link androidx.fragment.app.Fragment}
+ * Annotation that can be attached to a constructor with a single {@link LayoutRes} parameter
  * to denote what layout the component intends to inflate and set as its content.
  * <p>
- * This annotation is marked as {@link Inherited} and will therefore apply to subclasses
- * automatically.
- * <p>
  * It is strongly recommended that components that support this annotation specifically call
  * it out in their documentation.
+ * <pre>
+ * public class MainFragment extends Fragment {
+ *     public MainFragment() {
+ *         // This constructor is annotated with @ContentView
+ *         super(R.layout.main);
+ *     }
+ * }
+ * </pre>
  *
- * @see androidx.activity.ComponentActivity#onCreate(android.os.Bundle)
- * @see androidx.fragment.app.Fragment#onCreateView
+ * @see androidx.activity.ComponentActivity#ComponentActivity(int)
+ * @see androidx.fragment.app.Fragment#Fragment(int)
  */
-@Retention(RUNTIME)
-@Target({TYPE})
-@Inherited
+@Retention(CLASS)
+@Target({CONSTRUCTOR})
 public @interface ContentView {
-    @LayoutRes
-    int value();
 }
diff --git a/appcompat/api/1.1.0-alpha04.txt b/appcompat/api/1.1.0-alpha04.txt
index fdf6fc553a0..03862a1c660 100644
--- a/appcompat/api/1.1.0-alpha04.txt
+++ b/appcompat/api/1.1.0-alpha04.txt
@@ -218,6 +218,7 @@ package androidx.appcompat.app {
 
   public class AppCompatActivity extends androidx.fragment.app.FragmentActivity implements androidx.appcompat.app.ActionBarDrawerToggle.DelegateProvider androidx.appcompat.app.AppCompatCallback androidx.core.app.TaskStackBuilder.SupportParentable {
     ctor public AppCompatActivity();
+    ctor @ContentView public AppCompatActivity(@LayoutRes int);
     method public androidx.appcompat.app.AppCompatDelegate getDelegate();
     method public androidx.appcompat.app.ActionBarDrawerToggle.Delegate? getDrawerToggleDelegate();
     method public androidx.appcompat.app.ActionBar? getSupportActionBar();
diff --git a/appcompat/api/current.txt b/appcompat/api/current.txt
index fdf6fc553a0..03862a1c660 100644
--- a/appcompat/api/current.txt
+++ b/appcompat/api/current.txt
@@ -218,6 +218,7 @@ package androidx.appcompat.app {
 
   public class AppCompatActivity extends androidx.fragment.app.FragmentActivity implements androidx.appcompat.app.ActionBarDrawerToggle.DelegateProvider androidx.appcompat.app.AppCompatCallback androidx.core.app.TaskStackBuilder.SupportParentable {
     ctor public AppCompatActivity();
+    ctor @ContentView public AppCompatActivity(@LayoutRes int);
     method public androidx.appcompat.app.AppCompatDelegate getDelegate();
     method public androidx.appcompat.app.ActionBarDrawerToggle.Delegate? getDrawerToggleDelegate();
     method public androidx.appcompat.app.ActionBar? getSupportActionBar();
diff --git a/appcompat/src/main/java/androidx/appcompat/app/AppCompatActivity.java b/appcompat/src/main/java/androidx/appcompat/app/AppCompatActivity.java
index 23c9a09012a..8e7c7fd9c25 100644
--- a/appcompat/src/main/java/androidx/appcompat/app/AppCompatActivity.java
+++ b/appcompat/src/main/java/androidx/appcompat/app/AppCompatActivity.java
@@ -31,6 +31,7 @@ import android.view.ViewGroup;
 import android.view.Window;
 
 import androidx.annotation.CallSuper;
+import androidx.annotation.ContentView;
 import androidx.annotation.IdRes;
 import androidx.annotation.LayoutRes;
 import androidx.annotation.NonNull;
@@ -67,6 +68,30 @@ public class AppCompatActivity extends FragmentActivity implements AppCompatCall
     private AppCompatDelegate mDelegate;
     private Resources mResources;
 
+    /**
+     * Default constructor for AppCompatActivity. All Activities must have a default constructor
+     * for API 27 and lower devices or when using the default
+     * {@link android.app.AppComponentFactory}.
+     */
+    public AppCompatActivity() {
+        super();
+    }
+
+    /**
+     * Alternate constructor that can be used to provide a default layout
+     * that will be inflated as part of <code>super.onCreate(savedInstanceState)</code>.
+     *
+     * <p>This should generally be called from your constructor that takes no parameters,
+     * as is required for API 27 and lower or when using the default
+     * {@link android.app.AppComponentFactory}.
+     *
+     * @see #AppCompatActivity()
+     */
+    @ContentView
+    public AppCompatActivity(@LayoutRes int contentLayoutId) {
+        super(contentLayoutId);
+    }
+
     @Override
     protected void attachBaseContext(Context newBase) {
         super.attachBaseContext(newBase);
diff --git a/fragment/api/1.1.0-alpha06.txt b/fragment/api/1.1.0-alpha06.txt
index 22f79078af1..c945b0b4ff0 100644
--- a/fragment/api/1.1.0-alpha06.txt
+++ b/fragment/api/1.1.0-alpha06.txt
@@ -27,6 +27,7 @@ package androidx.fragment.app {
 
   public class Fragment implements android.content.ComponentCallbacks androidx.lifecycle.LifecycleOwner androidx.savedstate.SavedStateRegistryOwner android.view.View.OnCreateContextMenuListener androidx.lifecycle.ViewModelStoreOwner {
     ctor public Fragment();
+    ctor @ContentView public Fragment(@LayoutRes int);
     method public void dump(String, java.io.FileDescriptor?, java.io.PrintWriter, String[]?);
     method public final boolean equals(Object?);
     method public final androidx.fragment.app.FragmentActivity? getActivity();
@@ -157,6 +158,7 @@ package androidx.fragment.app {
 
   public class FragmentActivity extends androidx.activity.ComponentActivity implements androidx.core.app.ActivityCompat.OnRequestPermissionsResultCallback androidx.core.app.ActivityCompat.RequestPermissionsRequestCodeValidator {
     ctor public FragmentActivity();
+    ctor @ContentView public FragmentActivity(@LayoutRes int);
     method public androidx.fragment.app.FragmentManager getSupportFragmentManager();
     method @Deprecated public androidx.loader.app.LoaderManager getSupportLoaderManager();
     method public android.content.Context getThemedContext();
diff --git a/fragment/api/current.txt b/fragment/api/current.txt
index 22f79078af1..c945b0b4ff0 100644
--- a/fragment/api/current.txt
+++ b/fragment/api/current.txt
@@ -27,6 +27,7 @@ package androidx.fragment.app {
 
   public class Fragment implements android.content.ComponentCallbacks androidx.lifecycle.LifecycleOwner androidx.savedstate.SavedStateRegistryOwner android.view.View.OnCreateContextMenuListener androidx.lifecycle.ViewModelStoreOwner {
     ctor public Fragment();
+    ctor @ContentView public Fragment(@LayoutRes int);
     method public void dump(String, java.io.FileDescriptor?, java.io.PrintWriter, String[]?);
     method public final boolean equals(Object?);
     method public final androidx.fragment.app.FragmentActivity? getActivity();
@@ -157,6 +158,7 @@ package androidx.fragment.app {
 
   public class FragmentActivity extends androidx.activity.ComponentActivity implements androidx.core.app.ActivityCompat.OnRequestPermissionsResultCallback androidx.core.app.ActivityCompat.RequestPermissionsRequestCodeValidator {
     ctor public FragmentActivity();
+    ctor @ContentView public FragmentActivity(@LayoutRes int);
     method public androidx.fragment.app.FragmentManager getSupportFragmentManager();
     method @Deprecated public androidx.loader.app.LoaderManager getSupportLoaderManager();
     method public android.content.Context getThemedContext();
diff --git a/fragment/src/androidTest/java/androidx/fragment/app/FragmentFactoryTest.kt b/fragment/src/androidTest/java/androidx/fragment/app/FragmentFactoryTest.kt
index 1e12a684487..a90cccf97b4 100644
--- a/fragment/src/androidTest/java/androidx/fragment/app/FragmentFactoryTest.kt
+++ b/fragment/src/androidTest/java/androidx/fragment/app/FragmentFactoryTest.kt
@@ -17,7 +17,6 @@
 package androidx.fragment.app
 
 import android.os.Bundle
-import androidx.annotation.ContentView
 import androidx.fragment.app.test.EmptyFragmentTestActivity
 import androidx.fragment.test.R
 import androidx.test.annotation.UiThreadTest
@@ -87,8 +86,7 @@ class FragmentFactoryTest {
     }
 }
 
-@ContentView(R.layout.nested_inflated_fragment_parent)
-class ParentFragment : Fragment() {
+class ParentFragment : Fragment(R.layout.nested_inflated_fragment_parent) {
     var factory: FragmentFactory? = null
 
     override fun onCreate(savedInstanceState: Bundle?) {
diff --git a/fragment/src/androidTest/java/androidx/fragment/app/FragmentLifecycleTest.kt b/fragment/src/androidTest/java/androidx/fragment/app/FragmentLifecycleTest.kt
index d27247cf918..42d18fc4de2 100644
--- a/fragment/src/androidTest/java/androidx/fragment/app/FragmentLifecycleTest.kt
+++ b/fragment/src/androidTest/java/androidx/fragment/app/FragmentLifecycleTest.kt
@@ -25,7 +25,6 @@ import android.view.LayoutInflater
 import android.view.Menu
 import android.view.ViewGroup
 import android.widget.TextView
-import androidx.annotation.ContentView
 import androidx.core.view.ViewCompat
 import androidx.fragment.app.FragmentManager.FragmentLifecycleCallbacks
 import androidx.fragment.app.FragmentTestUtil.HostCallbacks
@@ -868,11 +867,10 @@ class FragmentLifecycleTest {
         }
     }
 
-    @ContentView(R.layout.nested_retained_inflated_fragment_parent)
-    class RetainedInflatedParentFragment : Fragment()
+    class RetainedInflatedParentFragment :
+        Fragment(R.layout.nested_retained_inflated_fragment_parent)
 
-    @ContentView(R.layout.nested_inflated_fragment_child)
-    class RetainedInflatedChildFragment : Fragment() {
+    class RetainedInflatedChildFragment : Fragment(R.layout.nested_inflated_fragment_child) {
         internal var mOnInflateCount = 0
 
         override fun onCreate(savedInstanceState: Bundle?) {
diff --git a/fragment/src/androidTest/java/androidx/fragment/app/FragmentTest.kt b/fragment/src/androidTest/java/androidx/fragment/app/FragmentTest.kt
index 8bf7bbdc3c2..85adb6c7ad6 100644
--- a/fragment/src/androidTest/java/androidx/fragment/app/FragmentTest.kt
+++ b/fragment/src/androidTest/java/androidx/fragment/app/FragmentTest.kt
@@ -20,7 +20,6 @@ import android.os.Bundle
 import android.view.View
 import android.view.ViewGroup
 import android.view.ViewTreeObserver
-import androidx.annotation.ContentView
 import androidx.annotation.RequiresApi
 import androidx.fragment.app.test.FragmentTestActivity
 import androidx.fragment.test.R
@@ -309,12 +308,9 @@ class FragmentTest {
         }
     }
 
-    @ContentView(R.layout.fragment_a)
-    class FragmentA : Fragment()
+    class FragmentA : Fragment(R.layout.fragment_a)
 
-    @ContentView(R.layout.fragment_b)
-    class FragmentB : Fragment()
+    class FragmentB : Fragment(R.layout.fragment_b)
 
-    @ContentView(R.layout.fragment_c)
-    class FragmentC : Fragment()
+    class FragmentC : Fragment(R.layout.fragment_c)
 }
diff --git a/fragment/src/androidTest/java/androidx/fragment/app/FragmentTransactionTest.kt b/fragment/src/androidTest/java/androidx/fragment/app/FragmentTransactionTest.kt
index 0c1e3fbac37..b66c15fed23 100644
--- a/fragment/src/androidTest/java/androidx/fragment/app/FragmentTransactionTest.kt
+++ b/fragment/src/androidTest/java/androidx/fragment/app/FragmentTransactionTest.kt
@@ -15,14 +15,10 @@
  */
 package androidx.fragment.app.test
 
-import org.junit.Assert.fail
-
 import android.content.Intent
 import android.os.Bundle
 import android.os.SystemClock
 import android.view.LayoutInflater
-
-import androidx.annotation.ContentView
 import androidx.fragment.app.Fragment
 import androidx.fragment.app.FragmentManager
 import androidx.fragment.app.FragmentTestUtil
@@ -34,8 +30,8 @@ import androidx.test.platform.app.InstrumentationRegistry
 import androidx.test.rule.ActivityTestRule
 import com.google.common.truth.Truth.assertThat
 import com.google.common.truth.Truth.assertWithMessage
-
 import org.junit.After
+import org.junit.Assert.fail
 import org.junit.Before
 import org.junit.Rule
 import org.junit.Test
@@ -407,8 +403,7 @@ class FragmentTransactionTest {
 
     private inner class NonStaticFragment : Fragment()
 
-    @ContentView(R.layout.fragment_a)
-    class OnGetLayoutInflaterFragment : Fragment() {
+    class OnGetLayoutInflaterFragment : Fragment(R.layout.fragment_a) {
         var onGetLayoutInflaterCalls = 0
         lateinit var baseLayoutInflater: LayoutInflater
 
diff --git a/fragment/src/androidTest/java/androidx/fragment/app/FragmentViewTest.kt b/fragment/src/androidTest/java/androidx/fragment/app/FragmentViewTest.kt
index c1d4d40154a..4b2ff74461d 100644
--- a/fragment/src/androidTest/java/androidx/fragment/app/FragmentViewTest.kt
+++ b/fragment/src/androidTest/java/androidx/fragment/app/FragmentViewTest.kt
@@ -15,14 +15,10 @@
  */
 package androidx.fragment.app
 
-import org.junit.Assert.fail
-
 import android.os.Bundle
 import android.view.LayoutInflater
 import android.view.View
 import android.view.ViewGroup
-
-import androidx.annotation.ContentView
 import androidx.fragment.app.test.FragmentTestActivity
 import androidx.fragment.test.R
 import androidx.test.ext.junit.runners.AndroidJUnit4
@@ -31,7 +27,7 @@ import androidx.test.platform.app.InstrumentationRegistry
 import androidx.test.rule.ActivityTestRule
 import com.google.common.truth.Truth.assertThat
 import com.google.common.truth.Truth.assertWithMessage
-
+import org.junit.Assert.fail
 import org.junit.Rule
 import org.junit.Test
 import org.junit.runner.RunWith
@@ -1029,8 +1025,7 @@ class FragmentViewTest {
         }
     }
 
-    @ContentView(R.layout.fragment_a)
-    class SimpleViewFragment : Fragment() {
+    class SimpleViewFragment : Fragment(R.layout.fragment_a) {
         var onCreateViewCount: Int = 0
 
         override fun onCreateView(
diff --git a/fragment/src/androidTest/java/androidx/fragment/app/NestedInflatedFragmentTest.kt b/fragment/src/androidTest/java/androidx/fragment/app/NestedInflatedFragmentTest.kt
index af65c8c2448..59c3d43507f 100644
--- a/fragment/src/androidTest/java/androidx/fragment/app/NestedInflatedFragmentTest.kt
+++ b/fragment/src/androidTest/java/androidx/fragment/app/NestedInflatedFragmentTest.kt
@@ -20,7 +20,6 @@ import android.os.Bundle
 import android.view.LayoutInflater
 import android.view.ViewGroup
 import android.widget.TextView
-import androidx.annotation.ContentView
 import androidx.fragment.app.test.FragmentTestActivity
 import androidx.fragment.test.R
 import androidx.test.annotation.UiThreadTest
@@ -83,8 +82,7 @@ class NestedInflatedFragmentTest {
         fm.executePendingTransactions()
     }
 
-    @ContentView(R.layout.nested_inflated_fragment_parent)
-    open class ParentFragment : Fragment()
+    open class ParentFragment : Fragment(R.layout.nested_inflated_fragment_parent)
 
     class UserVisibleHintParentFragment : ParentFragment() {
         override fun setUserVisibleHint(isVisibleToUser: Boolean) {
@@ -102,8 +100,7 @@ class NestedInflatedFragmentTest {
         }
     }
 
-    @ContentView(R.layout.nested_inflated_fragment_child)
-    class InflatedChildFragment : Fragment()
+    class InflatedChildFragment : Fragment(R.layout.nested_inflated_fragment_child)
 
     class SimpleFragment : Fragment() {
         override fun onCreateView(
diff --git a/fragment/src/androidTest/java/androidx/fragment/app/StrictFragment.kt b/fragment/src/androidTest/java/androidx/fragment/app/StrictFragment.kt
index b8faca2d4f1..61d74b5811d 100644
--- a/fragment/src/androidTest/java/androidx/fragment/app/StrictFragment.kt
+++ b/fragment/src/androidTest/java/androidx/fragment/app/StrictFragment.kt
@@ -18,13 +18,14 @@ package androidx.fragment.app
 
 import android.content.Context
 import android.os.Bundle
+import androidx.annotation.LayoutRes
 import com.google.common.truth.Truth.assertWithMessage
 
 /**
  * This fragment watches its primary lifecycle events and throws IllegalStateException
  * if any of them are called out of order or from a bad/unexpected state.
  */
-open class StrictFragment : Fragment() {
+open class StrictFragment(@LayoutRes contentLayoutId: Int = 0) : Fragment(contentLayoutId) {
     var currentState: Int = 0
 
     var calledOnAttach: Boolean = false
diff --git a/fragment/src/androidTest/java/androidx/fragment/app/StrictViewFragment.kt b/fragment/src/androidTest/java/androidx/fragment/app/StrictViewFragment.kt
index 5b367e46301..86062b96aee 100644
--- a/fragment/src/androidTest/java/androidx/fragment/app/StrictViewFragment.kt
+++ b/fragment/src/androidTest/java/androidx/fragment/app/StrictViewFragment.kt
@@ -25,8 +25,8 @@ import androidx.fragment.test.R
 import com.google.common.truth.Truth.assertWithMessage
 
 open class StrictViewFragment(
-    @LayoutRes val contentLayoutId: Int = R.layout.strict_view_fragment
-) : StrictFragment() {
+    @LayoutRes contentLayoutId: Int = R.layout.strict_view_fragment
+) : StrictFragment(contentLayoutId) {
 
     internal var onCreateViewCalled: Boolean = false
     internal var onViewCreatedCalled: Boolean = false
@@ -39,12 +39,9 @@ open class StrictViewFragment(
     ): View? {
         checkGetActivity()
         checkState("onCreateView", StrictFragment.CREATED)
-        var result = super.onCreateView(inflater, container, savedInstanceState)
-        if (result == null) {
-            result = inflater.inflate(contentLayoutId, container, false)
+        return super.onCreateView(inflater, container, savedInstanceState).also {
+            onCreateViewCalled = true
         }
-        onCreateViewCalled = true
-        return result
     }
 
     override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
diff --git a/fragment/src/androidTest/java/androidx/fragment/app/test/FragmentTestActivity.kt b/fragment/src/androidTest/java/androidx/fragment/app/test/FragmentTestActivity.kt
index 6ab2b107657..64dbc8d186a 100644
--- a/fragment/src/androidTest/java/androidx/fragment/app/test/FragmentTestActivity.kt
+++ b/fragment/src/androidTest/java/androidx/fragment/app/test/FragmentTestActivity.kt
@@ -18,7 +18,6 @@ package androidx.fragment.app.test
 import android.content.Context
 import android.content.Intent
 import android.os.Bundle
-import androidx.annotation.ContentView
 import androidx.fragment.app.Fragment
 import androidx.fragment.app.FragmentActivity
 import androidx.fragment.test.R
@@ -26,8 +25,7 @@ import androidx.fragment.test.R
 /**
  * A simple activity used for Fragment Transitions and lifecycle event ordering
  */
-@ContentView(R.layout.activity_content)
-class FragmentTestActivity : FragmentActivity() {
+class FragmentTestActivity : FragmentActivity(R.layout.activity_content) {
 
     class ParentFragment : Fragment() {
         var wasAttachedInTime: Boolean = false
diff --git a/fragment/src/androidTest/java/androidx/fragment/app/test/LoaderActivity.kt b/fragment/src/androidTest/java/androidx/fragment/app/test/LoaderActivity.kt
index ea44bf90e2b..9baf280fc5d 100644
--- a/fragment/src/androidTest/java/androidx/fragment/app/test/LoaderActivity.kt
+++ b/fragment/src/androidTest/java/androidx/fragment/app/test/LoaderActivity.kt
@@ -20,8 +20,6 @@ import android.content.Context
 import android.os.Bundle
 import android.view.View
 import android.widget.TextView
-
-import androidx.annotation.ContentView
 import androidx.fragment.app.Fragment
 import androidx.fragment.test.R
 import androidx.loader.app.LoaderManager
@@ -29,8 +27,8 @@ import androidx.loader.content.AsyncTaskLoader
 import androidx.loader.content.Loader
 import androidx.testutils.RecreatedActivity
 
-@ContentView(R.layout.activity_loader)
-class LoaderActivity : RecreatedActivity(), LoaderManager.LoaderCallbacks<String> {
+class LoaderActivity : RecreatedActivity(R.layout.activity_loader),
+    LoaderManager.LoaderCallbacks<String> {
 
     lateinit var textView: TextView
     lateinit var textViewB: TextView
@@ -75,8 +73,8 @@ class LoaderActivity : RecreatedActivity(), LoaderManager.LoaderCallbacks<String
         }
     }
 
-    @ContentView(R.layout.fragment_c)
-    class TextLoaderFragment : Fragment(), LoaderManager.LoaderCallbacks<String> {
+    class TextLoaderFragment : Fragment(R.layout.fragment_c),
+        LoaderManager.LoaderCallbacks<String> {
         lateinit var textView: TextView
 
         override fun onCreate(savedInstanceState: Bundle?) {
diff --git a/fragment/src/main/java/androidx/fragment/app/Fragment.java b/fragment/src/main/java/androidx/fragment/app/Fragment.java
index de3963dcf3f..89cf832443f 100644
--- a/fragment/src/main/java/androidx/fragment/app/Fragment.java
+++ b/fragment/src/main/java/androidx/fragment/app/Fragment.java
@@ -48,6 +48,7 @@ import android.widget.AdapterView;
 
 import androidx.annotation.CallSuper;
 import androidx.annotation.ContentView;
+import androidx.annotation.LayoutRes;
 import androidx.annotation.MainThread;
 import androidx.annotation.NonNull;
 import androidx.annotation.Nullable;
@@ -72,7 +73,6 @@ import androidx.savedstate.SavedStateRegistryOwner;
 import java.io.FileDescriptor;
 import java.io.PrintWriter;
 import java.lang.reflect.InvocationTargetException;
-import java.util.HashMap;
 import java.util.UUID;
 
 /**
@@ -250,8 +250,8 @@ public class Fragment implements ComponentCallbacks, OnCreateContextMenuListener
 
     SavedStateRegistryController mSavedStateRegistryController;
 
-    // Cache the ContentView layoutIds for Fragments.
-    private static final HashMap<Class, Integer> sAnnotationIds = new HashMap<>();
+    @LayoutRes
+    private int mContentLayoutId;
 
     /**
      * {@inheritDoc}
@@ -414,13 +414,14 @@ public class Fragment implements ComponentCallbacks, OnCreateContextMenuListener
     }
 
     /**
-     * Default constructor.  <strong>Every</strong> fragment must have an
-     * empty constructor, so it can be instantiated when restoring its
-     * activity's state.  It is strongly recommended that subclasses do not
-     * have other constructors with parameters, since these constructors
-     * will not be called when the fragment is re-instantiated; instead,
-     * arguments can be supplied by the caller with {@link #setArguments}
-     * and later retrieved by the Fragment with {@link #getArguments}.
+     * Constructor used by the default {@link FragmentFactory}. You must
+     * {@link FragmentManager#setFragmentFactory(FragmentFactory) set a custom FragmentFactory}
+     * if you want to use a non-default constructor to ensure that your constructor
+     * is called when the fragment is re-instantiated.
+     *
+     * <p>It is strongly recommended to supply arguments with {@link #setArguments}
+     * and later retrieved by the Fragment with {@link #getArguments}. These arguments
+     * are automatically saved and restored alongside the Fragment.
      *
      * <p>Applications should generally not implement a constructor. Prefer
      * {@link #onAttach(Context)} instead. It is the first place application code can run where
@@ -432,6 +433,19 @@ public class Fragment implements ComponentCallbacks, OnCreateContextMenuListener
         initLifecycle();
     }
 
+    /**
+     * Alternate constructor that can be used to provide a default layout
+     * that will be inflated by {@link #onCreateView(LayoutInflater, ViewGroup, Bundle)}.
+     *
+     * @see #Fragment()
+     * @see #onCreateView(LayoutInflater, ViewGroup, Bundle)
+     */
+    @ContentView
+    public Fragment(@LayoutRes int contentLayoutId) {
+        this();
+        mContentLayoutId = contentLayoutId;
+    }
+
     private void initLifecycle() {
         mLifecycleRegistry = new LifecycleRegistry(this);
         mSavedStateRegistryController = SavedStateRegistryController.create(this);
@@ -1616,9 +1630,8 @@ public class Fragment implements ComponentCallbacks, OnCreateContextMenuListener
      * Called to have the fragment instantiate its user interface view.
      * This is optional, and non-graphical fragments can return null. This will be called between
      * {@link #onCreate(Bundle)} and {@link #onActivityCreated(Bundle)}.
-     * <p>The default implementation looks for an {@link ContentView} annotation, inflating
-     * and returning that layout. If the annotation is not found or has an invalid layout resource
-     * id, this method returns null.
+     * <p>A default View can be returned by calling {@link #Fragment(int)} in your
+     * constructor. Otherwise, this method returns null.
      *
      * <p>It is recommended to <strong>only</strong> inflate the layout in this method and move
      * logic that operates on the returned View to {@link #onViewCreated(View, Bundle)}.
@@ -1639,18 +1652,8 @@ public class Fragment implements ComponentCallbacks, OnCreateContextMenuListener
     @Nullable
     public View onCreateView(@NonNull LayoutInflater inflater, @Nullable ViewGroup container,
             @Nullable Bundle savedInstanceState) {
-        Class<? extends Fragment> clazz = getClass();
-        if (!sAnnotationIds.containsKey(clazz)) {
-            ContentView annotation = clazz.getAnnotation(ContentView.class);
-            if (annotation != null) {
-                sAnnotationIds.put(clazz, annotation.value());
-            } else {
-                sAnnotationIds.put(clazz, null);
-            }
-        }
-        Integer layoutId = sAnnotationIds.get(clazz);
-        if (layoutId != null && layoutId != 0) {
-            return inflater.inflate(layoutId, container, false);
+        if (mContentLayoutId != 0) {
+            return inflater.inflate(mContentLayoutId, container, false);
         }
         return null;
     }
diff --git a/fragment/src/main/java/androidx/fragment/app/FragmentActivity.java b/fragment/src/main/java/androidx/fragment/app/FragmentActivity.java
index 4a4a1f10e84..6cee60b608b 100644
--- a/fragment/src/main/java/androidx/fragment/app/FragmentActivity.java
+++ b/fragment/src/main/java/androidx/fragment/app/FragmentActivity.java
@@ -37,6 +37,8 @@ import android.view.Window;
 import androidx.activity.ComponentActivity;
 import androidx.activity.OnBackPressedCallback;
 import androidx.annotation.CallSuper;
+import androidx.annotation.ContentView;
+import androidx.annotation.LayoutRes;
 import androidx.annotation.NonNull;
 import androidx.annotation.Nullable;
 import androidx.annotation.RestrictTo;
@@ -107,8 +109,33 @@ public class FragmentActivity extends ComponentActivity implements
     // for startActivityForResult calls where a result has not yet been delivered.
     SparseArrayCompat<String> mPendingFragmentActivityResults;
 
+    /**
+     * Default constructor for FragmentActivity. All Activities must have a default constructor
+     * for API 27 and lower devices or when using the default
+     * {@link android.app.AppComponentFactory}.
+     */
     public FragmentActivity() {
         super();
+        init();
+    }
+
+    /**
+     * Alternate constructor that can be used to provide a default layout
+     * that will be inflated as part of <code>super.onCreate(savedInstanceState)</code>.
+     *
+     * <p>This should generally be called from your constructor that takes no parameters,
+     * as is required for API 27 and lower or when using the default
+     * {@link android.app.AppComponentFactory}.
+     *
+     * @see #FragmentActivity()
+     */
+    @ContentView
+    public FragmentActivity(@LayoutRes int contentLayoutId) {
+        super(contentLayoutId);
+        init();
+    }
+
+    private void init() {
         // Route onBackPressed() callbacks to the FragmentManager
         getOnBackPressedDispatcher().addCallback(this, new OnBackPressedCallback() {
             @Override
diff --git a/testutils/src/main/java/androidx/testutils/RecreatedActivity.kt b/testutils/src/main/java/androidx/testutils/RecreatedActivity.kt
index 22b74aa9e9a..1463395f37f 100644
--- a/testutils/src/main/java/androidx/testutils/RecreatedActivity.kt
+++ b/testutils/src/main/java/androidx/testutils/RecreatedActivity.kt
@@ -17,6 +17,7 @@
 package androidx.testutils
 
 import android.os.Bundle
+import androidx.annotation.LayoutRes
 import androidx.fragment.app.FragmentActivity
 import java.util.concurrent.CountDownLatch
 
@@ -25,7 +26,9 @@ import java.util.concurrent.CountDownLatch
  * In order to use this class, have your activity extend it and call
  * [FragmentActivityUtils.recreateActivity] API.
  */
-open class RecreatedActivity : FragmentActivity() {
+open class RecreatedActivity(
+    @LayoutRes contentLayoutId: Int = 0
+) : FragmentActivity(contentLayoutId) {
 
     override fun onCreate(savedInstanceState: Bundle?) {
         super.onCreate(savedInstanceState)