Ensure page up/down always moves to first/last selectable item. (af9c5ea2) · Commits · e / os / android_frameworks_base

core/java/android/widget/ListView.java

+64 −15

Original line number	Diff line number	Diff line
		@@ -2058,17 +2058,61 @@ public class ListView extends AbsListView {
		position--;
		}
		}
		}

		if (position < 0 \|\| position >= count) {
		return INVALID_POSITION;
		}

		return position;
		}

		/**
		* Find a position that can be selected (i.e., is not a separator). If there
		* are no selectable positions in the specified direction from the starting
		* position, searches in the opposite direction from the starting position
		* to the current position.
		*
		* @param current the current position
		* @param position the starting position
		* @param lookDown whether to look down for other positions
		* @return the next selectable position, or {@link #INVALID_POSITION} if
		* nothing can be found
		*/
		int lookForSelectablePositionAfter(int current, int position, boolean lookDown) {
		final ListAdapter adapter = mAdapter;
		if (adapter == null \|\| isInTouchMode()) {
		return INVALID_POSITION;
		}

		// First check after the starting position in the specified direction.
		final int after = lookForSelectablePosition(position, lookDown);
		if (after != INVALID_POSITION) {
		return after;
		}

		// Then check between the starting position and the current position.
		final int count = adapter.getCount();
		current = MathUtils.constrain(current, -1, count - 1);
		if (lookDown) {
		position = Math.min(position - 1, count - 1);
		while ((position > current) && !adapter.isEnabled(position)) {
		position--;
		}
		if (position <= current) {
		return INVALID_POSITION;
		}
		} else {
		if (position < 0 \|\| position >= count) {
		position = Math.max(0, position + 1);
		while ((position < current) && !adapter.isEnabled(position)) {
		position++;
		}
		if (position >= current) {
		return INVALID_POSITION;
		}
		return position;
		}

		return position;
		}

		/**
		@@ -2281,27 +2325,30 @@ public class ListView extends AbsListView {
		* @return whether selection was moved
		*/
		boolean pageScroll(int direction) {
		int nextPage = -1;
		boolean down = false;
		final int nextPage;
		final boolean down;

		if (direction == FOCUS_UP) {
		nextPage = Math.max(0, mSelectedPosition - getChildCount() - 1);
		down = false;
		} else if (direction == FOCUS_DOWN) {
		nextPage = Math.min(mItemCount - 1, mSelectedPosition + getChildCount() - 1);
		down = true;
		} else {
		return false;
		}

		if (nextPage >= 0) {
		int position = lookForSelectablePosition(nextPage, down);
		final int position = lookForSelectablePositionAfter(mSelectedPosition, nextPage, down);
		if (position >= 0) {
		mLayoutMode = LAYOUT_SPECIFIC;
		mSpecificTop = mPaddingTop + getVerticalFadingEdgeLength();

		if (down && position > mItemCount - getChildCount()) {
		if (down && (position > (mItemCount - getChildCount()))) {
		mLayoutMode = LAYOUT_FORCE_BOTTOM;
		}

		if (!down && position < getChildCount()) {
		if (!down && (position < getChildCount())) {
		mLayoutMode = LAYOUT_FORCE_TOP;
		}

		@@ -2319,18 +2366,18 @@ public class ListView extends AbsListView {
		}

		/**
		* Go to the last or first item if possible (not worrying about panning across or navigating
		* within the internal focus of the currently selected item.)
		* Go to the last or first item if possible (not worrying about panning
		* across or navigating within the internal focus of the currently selected
		* item.)
		*
		* @param direction either {@link View#FOCUS_UP} or {@link View#FOCUS_DOWN}
		*
		* @return whether selection was moved
		*/
		boolean fullScroll(int direction) {
		boolean moved = false;
		if (direction == FOCUS_UP) {
		if (mSelectedPosition != 0) {
		int position = lookForSelectablePosition(0, true);
		final int position = lookForSelectablePositionAfter(mSelectedPosition, 0, true);
		if (position >= 0) {
		mLayoutMode = LAYOUT_FORCE_TOP;
		setSelectionInt(position);
		@@ -2339,8 +2386,10 @@ public class ListView extends AbsListView {
		moved = true;
		}
		} else if (direction == FOCUS_DOWN) {
		if (mSelectedPosition < mItemCount - 1) {
		int position = lookForSelectablePosition(mItemCount - 1, true);
		final int lastItem = (mItemCount - 1);
		if (mSelectedPosition < lastItem) {
		final int position = lookForSelectablePositionAfter(
		mSelectedPosition, lastItem, false);
		if (position >= 0) {
		mLayoutMode = LAYOUT_FORCE_BOTTOM;
		setSelectionInt(position);