Prevent ListView from scrolling/flinging its content when the content fits on screen.
Change-Id: Id46313bca3ae53b0717cd74a4a6f889a01f9fcb1
diff --git a/core/java/android/view/View.java b/core/java/android/view/View.java
index 425ccab..d569220 100644
--- a/core/java/android/view/View.java
+++ b/core/java/android/view/View.java
@@ -46,7 +46,6 @@
import android.os.SystemProperties;
import android.util.AttributeSet;
import android.util.Config;
-import android.util.DisplayMetrics;
import android.util.EventLog;
import android.util.Log;
import android.util.Pool;
diff --git a/core/java/android/widget/AbsListView.java b/core/java/android/widget/AbsListView.java
index 67721c9..2f292d5 100644
--- a/core/java/android/widget/AbsListView.java
+++ b/core/java/android/widget/AbsListView.java
@@ -1996,7 +1996,10 @@
if (y != mLastY) {
deltaY -= mMotionCorrection;
int incrementalDeltaY = mLastY != Integer.MIN_VALUE ? y - mLastY : deltaY;
- trackMotionScroll(deltaY, incrementalDeltaY);
+ // No need to do all this work if we're not going to move anyway
+ if (incrementalDeltaY != 0) {
+ trackMotionScroll(deltaY, incrementalDeltaY);
+ }
// Check to see if we have bumped into the scroll limit
View motionView = this.getChildAt(mMotionPosition - mFirstPosition);
@@ -2063,7 +2066,7 @@
if (mSelector != null) {
Drawable d = mSelector.getCurrent();
if (d != null && d instanceof TransitionDrawable) {
- ((TransitionDrawable)d).resetTransition();
+ ((TransitionDrawable) d).resetTransition();
}
}
postDelayed(new Runnable() {
@@ -2087,15 +2090,27 @@
mTouchMode = TOUCH_MODE_REST;
break;
case TOUCH_MODE_SCROLL:
- final VelocityTracker velocityTracker = mVelocityTracker;
- velocityTracker.computeCurrentVelocity(1000, mMaximumVelocity);
- final int initialVelocity = (int) velocityTracker.getYVelocity();
- if (Math.abs(initialVelocity) > mMinimumVelocity && (getChildCount() > 0)) {
- if (mFlingRunnable == null) {
- mFlingRunnable = new FlingRunnable();
+ final int childCount = getChildCount();
+ if (childCount > 0) {
+ if (mFirstPosition == 0 && getChildAt(0).getTop() >= mListPadding.top &&
+ mFirstPosition + childCount < mItemCount &&
+ getChildAt(childCount - 1).getBottom() <=
+ getHeight() - mListPadding.bottom) {
+ mTouchMode = TOUCH_MODE_REST;
+ reportScrollStateChange(OnScrollListener.SCROLL_STATE_IDLE);
+ } else {
+ final VelocityTracker velocityTracker = mVelocityTracker;
+ velocityTracker.computeCurrentVelocity(1000, mMaximumVelocity);
+ final int initialVelocity = (int) velocityTracker.getYVelocity();
+
+ if (Math.abs(initialVelocity) > mMinimumVelocity) {
+ if (mFlingRunnable == null) {
+ mFlingRunnable = new FlingRunnable();
+ }
+ reportScrollStateChange(OnScrollListener.SCROLL_STATE_FLING);
+ mFlingRunnable.start(-initialVelocity);
+ }
}
- reportScrollStateChange(OnScrollListener.SCROLL_STATE_FLING);
- mFlingRunnable.start(-initialVelocity);
} else {
mTouchMode = TOUCH_MODE_REST;
reportScrollStateChange(OnScrollListener.SCROLL_STATE_IDLE);
diff --git a/core/java/android/widget/ListView.java b/core/java/android/widget/ListView.java
index 993b7cb..6316864 100644
--- a/core/java/android/widget/ListView.java
+++ b/core/java/android/widget/ListView.java
@@ -1328,19 +1328,23 @@
// Make sure we are 1) Too low, and 2) Either there are more rows below the
// last row or the last row is scrolled off the bottom of the drawable area
- if (topOffset > 0 && (lastPosition < mItemCount - 1 || lastBottom > end)) {
- if (lastPosition == mItemCount - 1 ) {
- // Don't pull the bottom too far up
- topOffset = Math.min(topOffset, lastBottom - end);
- }
- // Move everything up
- offsetChildrenTopAndBottom(-topOffset);
- if (lastPosition < mItemCount - 1) {
- // Fill the gap that was opened below the last position with more rows, if
- // possible
- fillDown(lastPosition + 1, lastChild.getBottom() + mDividerHeight);
- // Close up the remaining gap
- adjustViewsUpOrDown();
+ if (topOffset > 0) {
+ if (lastPosition < mItemCount - 1 || lastBottom > end) {
+ if (lastPosition == mItemCount - 1) {
+ // Don't pull the bottom too far up
+ topOffset = Math.min(topOffset, lastBottom - end);
+ }
+ // Move everything up
+ offsetChildrenTopAndBottom(-topOffset);
+ if (lastPosition < mItemCount - 1) {
+ // Fill the gap that was opened below the last position with more rows, if
+ // possible
+ fillDown(lastPosition + 1, lastChild.getBottom() + mDividerHeight);
+ // Close up the remaining gap
+ adjustViewsUpOrDown();
+ }
+ } else if (lastPosition == mItemCount - 1) {
+ adjustViewsUpOrDown();
}
}
}
