For pre-N apps, cascade LOCATION and DROP events. (140adada) · Commits · e / os / android_frameworks_base

core/java/android/view/View.java

+13 −0

Original line number	Diff line number	Diff line
		@@ -829,6 +829,17 @@ public class View implements Drawable.Callback, KeyEvent.Callback,
		*/
		protected static boolean sPreserveMarginParamsInLayoutParamConversion;

		/**
		* Prior to N, when drag enters into child of a view that has already received an
		* ACTION_DRAG_ENTERED event, the parent doesn't get a ACTION_DRAG_EXITED event.
		* ACTION_DRAG_LOCATION and ACTION_DROP were delivered to the parent of a view that returned
		* false from its event handler for these events.
		* Starting from N, the parent will get ACTION_DRAG_EXITED event before the child gets its
		* ACTION_DRAG_ENTERED. ACTION_DRAG_LOCATION and ACTION_DROP are never propagated to the parent.
		* sCascadedDragDrop is true for pre-N apps for backwards compatibility implementation.
		*/
		static boolean sCascadedDragDrop;

		/**
		* This view does not want keystrokes. Use with TAKES_FOCUS_MASK when
		* calling setFlags.
		@@ -4065,6 +4076,8 @@ public class View implements Drawable.Callback, KeyEvent.Callback,
		// in apps so we target check it to avoid breaking existing apps.
		sPreserveMarginParamsInLayoutParamConversion = targetSdkVersion >= N;

		sCascadedDragDrop = targetSdkVersion < N;

		sCompatibilityDone = true;
		}
		}

+12 −5

Original line number	Diff line number	Diff line
		@@ -1451,7 +1451,7 @@ public abstract class ViewGroup extends View implements ViewParent, ViewManager
		View target = findFrontmostDroppableChildAt(event.mX, event.mY, localPoint);

		if (target != mCurrentDragChild) {
		if (mContext.getApplicationInfo().targetSdkVersion < Build.VERSION_CODES.N) {
		if (sCascadedDragDrop) {
		// For pre-Nougat apps, make sure that the whole hierarchy of views that contain
		// the drag location is kept in the state between ENTERED and EXITED events.
		// (Starting with N, only the innermost view will be in that state).
		@@ -1494,11 +1494,18 @@ public abstract class ViewGroup extends View implements ViewParent, ViewManager
		event.mX = tx;
		event.mY = ty;

		if (!event.mEventHandlerWasCalled && mIsInterestedInDrag) {
		// The child didn't invoke any event handler, but this view is interested in
		// drag, so the event goes to this view.
		if (mIsInterestedInDrag) {
		final boolean eventWasConsumed;
		if (sCascadedDragDrop) {
		eventWasConsumed = retval;
		} else {
		eventWasConsumed = event.mEventHandlerWasCalled;
		}

		if (!eventWasConsumed) {
		retval = super.dispatchDragEvent(event);
		}
		}
		} else {
		retval = super.dispatchDragEvent(event);
		}

+2 −2

Original line number	Diff line number	Diff line
		@@ -5524,7 +5524,7 @@ public final class ViewRootImpl implements ViewParent,
		// A direct EXITED event means that the window manager knows we've just crossed
		// a window boundary, so the current drag target within this one must have
		// just been exited. Send the EXITED notification to the current drag view, if any.
		if (mTargetSdkVersion < Build.VERSION_CODES.N) {
		if (View.sCascadedDragDrop) {
		mView.dispatchDragEnterExitInPreN(event);
		}
		setDragFocus(null, event);
		@@ -5644,7 +5644,7 @@ public final class ViewRootImpl implements ViewParent,
		}

		public void setDragFocus(View newDragTarget, DragEvent event) {
		if (mCurrentDragView != newDragTarget && mTargetSdkVersion >= Build.VERSION_CODES.N) {
		if (mCurrentDragView != newDragTarget && !View.sCascadedDragDrop) {
		// Send EXITED and ENTERED notifications to the old and new drag focus views.

		final float tx = event.mX;