[Predictive Transitions] Added predictive transition support for fragments and views to the Material motion library, and enabled it in shared axis fragment transition demo.

This allows all MaterialVisibility transitions to be predictive, although each individual transition must be opted-in in order to be predictive/seekable.

Resolves #3619

PiperOrigin-RevId: 587108521

Author: afohrman

build.gradle

@@ -37,7 +37,7 @@ ext {
     recyclerViewSelection        : '1.0.0',
     resourceInspectionAnnotation : '1.0.1',
     resourceInspectionProcessor  : '1.0.1',
-    transition                   : '1.2.0',
+    transition                   : '1.5.0-alpha04',
     vectorDrawable               : '1.1.0',
     viewpager2                   : '1.0.0',
     dynamicanimation             : '1.0.0',

catalog/java/io/material/catalog/transition/TransitionSharedAxisDemoFragment.java

@@ -20,13 +20,15 @@
 
 import android.os.Bundle;
 import androidx.fragment.app.Fragment;
+import androidx.fragment.app.FragmentTransaction;
 import android.view.LayoutInflater;
 import android.view.View;
 import android.view.ViewGroup;
-import androidx.activity.OnBackPressedCallback;
 import androidx.annotation.LayoutRes;
 import androidx.annotation.NonNull;
 import androidx.annotation.Nullable;
+import androidx.transition.Transition;
+import androidx.transition.TransitionListenerAdapter;
 import com.google.android.material.transition.MaterialSharedAxis;
 import io.material.catalog.feature.DemoFragment;
 
@@ -36,14 +38,6 @@ public class TransitionSharedAxisDemoFragment extends DemoFragment {
   private static final int LAYOUT_RES_ID_START = R.layout.cat_transition_shared_axis_start;
   private static final int LAYOUT_RES_ID_END = R.layout.cat_transition_shared_axis_end;
 
-  private final OnBackPressedCallback onBackPressedCallback =
-      new OnBackPressedCallback(/* enabled= */ false) {
-        @Override
-        public void handleOnBackPressed() {
-          replaceFragment(LAYOUT_RES_ID_START);
-        }
-      };
-
   private SharedAxisHelper sharedAxisHelper;
 
   @Override
@@ -58,12 +52,18 @@ public View onCreateDemoView(
   @Override
   public void onViewCreated(@NonNull View view, @Nullable Bundle bundle) {
     sharedAxisHelper = new SharedAxisHelper(view.findViewById(R.id.controls_layout));
-    requireActivity().getOnBackPressedDispatcher().addCallback(this, onBackPressedCallback);
 
-    replaceFragment(LAYOUT_RES_ID_START);
+    Fragment fragment = TransitionSimpleLayoutFragment.newInstance(LAYOUT_RES_ID_START);
+
+    requireActivity()
+        .getSupportFragmentManager()
+        .beginTransaction()
+        .replace(R.id.fragment_container, fragment)
+        .commit();
 
     sharedAxisHelper.setBackButtonOnClickListener(v -> replaceFragment(LAYOUT_RES_ID_START));
     sharedAxisHelper.setNextButtonOnClickListener(v -> replaceFragment(LAYOUT_RES_ID_END));
+    sharedAxisHelper.updateButtonsEnabled(true);
   }
 
   private void replaceFragment(@LayoutRes int layoutResId) {
@@ -73,14 +73,28 @@ private void replaceFragment(@LayoutRes int layoutResId) {
     // Set the transition as the Fragment's enter transition. This will be used when the fragment
     // is added to the container and re-used when the fragment is removed from the container.
     fragment.setEnterTransition(createTransition(entering));
+    if (entering) {
+      fragment.setReturnTransition(createTransition(false));
+    } else {
+      // Pop the backstack if manually transitioning to the start fragment to remove the end
+      // fragment from the back stack without a back event.
+      requireActivity().getSupportFragmentManager().popBackStack();
+    }
+
+    getFragmentTransaction(fragment, entering).commit();
+  }
 
-    getChildFragmentManager()
-        .beginTransaction()
-        .replace(R.id.fragment_container, fragment)
-        .commit();
+  private FragmentTransaction getFragmentTransaction(@NonNull Fragment fragment, boolean entering) {
+    return entering
+        ? getFragmentTransaction(fragment).addToBackStack(/* name= */ null)
+        : getFragmentTransaction(fragment);
+  }
 
-    sharedAxisHelper.updateButtonsEnabled(!entering);
-    onBackPressedCallback.setEnabled(entering);
+  private FragmentTransaction getFragmentTransaction(@NonNull Fragment fragment) {
+    return requireActivity()
+        .getSupportFragmentManager()
+        .beginTransaction()
+        .replace(R.id.fragment_container, fragment);
   }
 
   private MaterialSharedAxis createTransition(boolean entering) {
@@ -92,6 +106,18 @@ private MaterialSharedAxis createTransition(boolean entering) {
     // Fragment's layout.
     transition.addTarget(R.id.start_root);
     transition.addTarget(R.id.end_root);
+    transition.addListener(
+        new TransitionListenerAdapter() {
+          @Override
+          public void onTransitionStart(@NonNull Transition transition) {
+            sharedAxisHelper.updateButtonsEnabled(!entering);
+          }
+
+          @Override
+          public void onTransitionCancel(@NonNull Transition transition) {
+            sharedAxisHelper.updateButtonsEnabled(entering);
+          }
+        });
 
     return transition;
   }

lib/java/com/google/android/material/transition/MaterialVisibility.java

@@ -176,4 +176,10 @@ int getEasingThemeAttrResId(boolean appearing) {
   TimeInterpolator getDefaultEasingInterpolator(boolean appearing) {
     return AnimationUtils.FAST_OUT_SLOW_IN_INTERPOLATOR;
   }
+
+  // STRIP-FROM-PLATFORM-TRANSITIONS-PACKAGE
+  @Override // STRIP-FROM-PLATFORM-TRANSITIONS-PACKAGE
+  public boolean isSeekingSupported() { // STRIP-FROM-PLATFORM-TRANSITIONS-PACKAGE
+    return true; // STRIP-FROM-PLATFORM-TRANSITIONS-PACKAGE
+  } // STRIP-FROM-PLATFORM-TRANSITIONS-PACKAGE
 }

lib/java/com/google/android/material/transition/platform/MaterialVisibility.java

@@ -181,4 +181,10 @@ int getEasingThemeAttrResId(boolean appearing) {
   TimeInterpolator getDefaultEasingInterpolator(boolean appearing) {
     return AnimationUtils.FAST_OUT_SLOW_IN_INTERPOLATOR;
   }
+
+
+
+
+
+
 }