Make ScrollView only do overscroll if you're grabbing the child view. (9f0e8eea) · Commits · e / os / android_frameworks_base

core/java/android/widget/ScrollView.java

+49 −21

Original line number	Diff line number	Diff line
		@@ -22,6 +22,7 @@ import android.content.Context;
		import android.content.res.TypedArray;
		import android.graphics.Rect;
		import android.util.AttributeSet;
		import android.util.Log;
		import android.view.FocusFinder;
		import android.view.KeyEvent;
		import android.view.MotionEvent;
		@@ -51,6 +52,8 @@ import java.util.List;
		* <p>ScrollView only supports vertical scrolling.
		*/
		public class ScrollView extends FrameLayout {
		private static final String TAG = "ScrollView";

		static final int ANIMATED_SCROLL_GAP = 250;

		static final float MAX_SCROLL_FACTOR = 0.5f;
		@@ -360,6 +363,17 @@ public class ScrollView extends FrameLayout {
		return handled;
		}

		private boolean inChild(int x, int y) {
		if (getChildCount() > 0) {
		final View child = getChildAt(0);
		return !(y < child.getTop()
		\|\| y >= child.getBottom()
		\|\| x < child.getLeft()
		\|\| x >= child.getRight());
		}
		return false;
		}

		@Override
		public boolean onInterceptTouchEvent(MotionEvent ev) {
		/*
		@@ -399,6 +413,11 @@ public class ScrollView extends FrameLayout {
		break;

		case MotionEvent.ACTION_DOWN:
		if (!inChild((int)ev.getX(), (int)y)) {
		mIsBeingDragged = false;
		break;
		}

		/* Remember location of down touch */
		mLastMotionY = y;

		@@ -451,10 +470,16 @@ public class ScrollView extends FrameLayout {
		mScroller.abortAnimation();
		}

		if (!inChild((int)ev.getX(), (int)y)) {
		mIsBeingDragged = false;
		return false;
		}

		// Remember where the motion event started
		mLastMotionY = y;
		break;
		case MotionEvent.ACTION_MOVE:
		if (mIsBeingDragged) {
		// Scroll to follow the motion event
		final int deltaY = (int) (mLastMotionY - y);
		mLastMotionY = y;
		@@ -462,7 +487,9 @@ public class ScrollView extends FrameLayout {
		overscrollBy(0, deltaY, 0, mScrollY, 0, getScrollRange(),
		0, getOverscrollMax());
		break;
		}
		case MotionEvent.ACTION_UP:
		if (mIsBeingDragged) {
		final VelocityTracker velocityTracker = mVelocityTracker;
		velocityTracker.computeCurrentVelocity(1000, mMaximumVelocity);
		int initialVelocity = (int) velocityTracker.getYVelocity();
		@@ -483,6 +510,7 @@ public class ScrollView extends FrameLayout {
		mVelocityTracker = null;
		}
		}
		}
		return true;
		}