Only modify add Transition targets when they aren't targeted. (7ce5d75d) · Commits · e / os / android_frameworks_base

core/java/android/app/BackStackRecord.java

+71 −21

Original line number	Diff line number	Diff line
		@@ -38,6 +38,7 @@ import android.view.ViewTreeObserver;
		import java.io.FileDescriptor;
		import java.io.PrintWriter;
		import java.util.ArrayList;
		import java.util.List;

		final class BackStackState implements Parcelable {
		final int[] mOps;
		@@ -1055,7 +1056,7 @@ final class BackStackRecord extends FragmentTransaction implements
		}

		private static ArrayList<View> captureExitingViews(Transition exitTransition,
		Fragment outFragment, ArrayMap<String, View> namedViews) {
		Fragment outFragment, ArrayMap<String, View> namedViews, View nonExistentView) {
		ArrayList<View> viewList = null;
		if (exitTransition != null) {
		viewList = new ArrayList<View>();
		@@ -1064,8 +1065,11 @@ final class BackStackRecord extends FragmentTransaction implements
		if (namedViews != null) {
		viewList.removeAll(namedViews.values());
		}
		if (!viewList.isEmpty()) {
		viewList.add(nonExistentView);
		addTargets(exitTransition, viewList);
		}
		}
		return viewList;
		}

		@@ -1132,11 +1136,8 @@ final class BackStackRecord extends FragmentTransaction implements
		namedViews = mapSharedElementsIn(state, isBack, inFragment);
		removeTargets(sharedElementTransition, sharedElementTargets);
		sharedElementTargets.clear();
		if (namedViews.isEmpty()) {
		sharedElementTargets.add(state.nonExistentView);
		} else {
		sharedElementTargets.addAll(namedViews.values());
		}

		addTargets(sharedElementTransition, sharedElementTargets);

		@@ -1153,6 +1154,9 @@ final class BackStackRecord extends FragmentTransaction implements
		if (namedViews != null) {
		enteringViews.removeAll(namedViews.values());
		}
		enteringViews.add(state.nonExistentView);
		// We added this earlier to prevent any views being targeted.
		enterTransition.removeTarget(state.nonExistentView);
		addTargets(enterTransition, enteringViews);
		}
		setSharedElementEpicenter(enterTransition, state);
		@@ -1293,11 +1297,8 @@ final class BackStackRecord extends FragmentTransaction implements
		ArrayList<View> sharedElementTargets = new ArrayList<View>();
		if (sharedElementTransition != null) {
		namedViews = remapSharedElements(state, outFragment, isBack);
		if (namedViews.isEmpty()) {
		sharedElementTargets.add(state.nonExistentView);
		} else {
		sharedElementTargets.addAll(namedViews.values());
		}
		addTargets(sharedElementTransition, sharedElementTargets);

		// Notify the start of the transition.
		@@ -1310,7 +1311,7 @@ final class BackStackRecord extends FragmentTransaction implements
		}

		ArrayList<View> exitingViews = captureExitingViews(exitTransition, outFragment,
		namedViews);
		namedViews, state.nonExistentView);
		if (exitingViews == null \|\| exitingViews.isEmpty()) {
		exitTransition = null;
		}
		@@ -1388,19 +1389,68 @@ final class BackStackRecord extends FragmentTransaction implements
		}
		}

		private static void removeTargets(Transition transition, ArrayList<View> views) {
		int numViews = views.size();
		for (int i = 0; i < numViews; i++) {
		/**
		* This method removes the views from transitions that target ONLY those views.
		* The views list should match those added in addTargets and should contain
		* one view that is not in the view hierarchy (state.nonExistentView).
		*/
		public static void removeTargets(Transition transition, ArrayList<View> views) {
		if (transition instanceof TransitionSet) {
		TransitionSet set = (TransitionSet) transition;
		int numTransitions = set.getTransitionCount();
		for (int i = 0; i < numTransitions; i++) {
		Transition child = set.getTransitionAt(i);
		removeTargets(child, views);
		}
		} else if (!hasSimpleTarget(transition)) {
		List<View> targets = transition.getTargets();
		if (targets != null && targets.size() == views.size() &&
		targets.containsAll(views)) {
		// We have an exact match. We must have added these earlier in addTargets
		for (int i = views.size() - 1; i >= 0; i--) {
		transition.removeTarget(views.get(i));
		}
		}
		}
		}

		private static void addTargets(Transition transition, ArrayList<View> views) {
		/**
		* This method adds views as targets to the transition, but only if the transition
		* doesn't already have a target. It is best for views to contain one View object
		* that does not exist in the view hierarchy (state.nonExistentView) so that
		* when they are removed later, a list match will suffice to remove the targets.
		* Otherwise, if you happened to have targeted the exact views for the transition,
		* the removeTargets call will remove them unexpectedly.
		*/
		public static void addTargets(Transition transition, ArrayList<View> views) {
		if (transition instanceof TransitionSet) {
		TransitionSet set = (TransitionSet) transition;
		int numTransitions = set.getTransitionCount();
		for (int i = 0; i < numTransitions; i++) {
		Transition child = set.getTransitionAt(i);
		addTargets(child, views);
		}
		} else if (!hasSimpleTarget(transition)) {
		List<View> targets = transition.getTargets();
		if (isNullOrEmpty(targets)) {
		// We can just add the target views
		int numViews = views.size();
		for (int i = 0; i < numViews; i++) {
		transition.addTarget(views.get(i));
		}
		}
		}
		}

		private static boolean hasSimpleTarget(Transition transition) {
		return !isNullOrEmpty(transition.getTargetIds()) \|\|
		!isNullOrEmpty(transition.getTargetNames()) \|\|
		!isNullOrEmpty(transition.getTargetTypes());
		}

		private static boolean isNullOrEmpty(List list) {
		return list == null \|\| list.isEmpty();
		}

		/**
		* Remaps a name-to-View map, substituting different names for keys.