Improve ListView smooth scrolling timing (234a5715) · Commits · e / os / android_frameworks_base

core/java/android/widget/AbsListView.java

+15 −6

Original line number	Diff line number	Diff line
		@@ -16,11 +16,12 @@

		package android.widget;

		import com.android.internal.R;

		import android.content.Context;
		import android.content.Intent;
		import android.content.res.TypedArray;
		import android.graphics.Canvas;
		import android.graphics.Color;
		import android.graphics.Rect;
		import android.graphics.drawable.Drawable;
		import android.graphics.drawable.TransitionDrawable;
		@@ -56,8 +57,6 @@ import android.view.inputmethod.InputConnection;
		import android.view.inputmethod.InputConnectionWrapper;
		import android.view.inputmethod.InputMethodManager;

		import com.android.internal.R;

		import java.util.ArrayList;
		import java.util.List;

		@@ -3074,8 +3073,10 @@ public abstract class AbsListView extends AdapterView<ListAdapter> implements Te

		// Estimate how many screens we should travel
		final float screenTravelCount = (float) viewTravelCount / childCount;
		mScrollDuration = (int) (SCROLL_DURATION / screenTravelCount);
		mScrollDuration = screenTravelCount < 1 ? (int) (screenTravelCount * SCROLL_DURATION) :
		(int) (SCROLL_DURATION / screenTravelCount);
		mLastSeenPos = INVALID_POSITION;

		post(this);
		}

		@@ -3213,9 +3214,15 @@ public abstract class AbsListView extends AdapterView<ListAdapter> implements Te
		}

		case MOVE_OFFSET: {
		final int childCount = getChildCount();
		if (mLastSeenPos == firstPos) {
		// No new views, let things keep going.
		post(this);
		return;
		}

		mLastSeenPos = firstPos;

		final int childCount = getChildCount();
		final int position = mTargetPos;
		final int lastPos = firstPos + childCount - 1;

		@@ -3228,7 +3235,9 @@ public abstract class AbsListView extends AdapterView<ListAdapter> implements Te
		} else {
		// On-screen, just scroll.
		final int targetTop = getChildAt(position - firstPos).getTop();
		smoothScrollBy(targetTop - mOffsetFromTop, mScrollDuration);
		final int distance = targetTop - mOffsetFromTop;
		smoothScrollBy(distance,
		(int) (mScrollDuration * ((float) distance / getHeight())));
		}
		break;
		}