Add SHIFT+Click selection support. (e63dce7f) · Commits · e / os / android_frameworks_base

packages/DocumentsUI/src/com/android/documentsui/MultiSelectManager.java

+195 −13

Original line number	Original line	Diff line number	Diff line
	@@ -16,6 +16,7 @@

	package com.android.documentsui;		package com.android.documentsui;

			import static com.android.internal.util.Preconditions.checkArgument;
	import static com.android.internal.util.Preconditions.checkNotNull;		import static com.android.internal.util.Preconditions.checkNotNull;
	import static com.android.internal.util.Preconditions.checkState;		import static com.android.internal.util.Preconditions.checkState;

	@@ -26,9 +27,12 @@ import android.util.Log;
	import android.util.SparseBooleanArray;		import android.util.SparseBooleanArray;
	import android.view.GestureDetector;		import android.view.GestureDetector;
	import android.view.GestureDetector.OnGestureListener;		import android.view.GestureDetector.OnGestureListener;
			import android.view.KeyEvent;
	import android.view.MotionEvent;		import android.view.MotionEvent;
	import android.view.View;		import android.view.View;

			import com.android.internal.util.Preconditions;

	import com.google.common.annotations.VisibleForTesting;		import com.google.common.annotations.VisibleForTesting;

	import java.util.ArrayList;		import java.util.ArrayList;
	@@ -43,9 +47,11 @@ public final class MultiSelectManager {
	private static final boolean DEBUG = false;		private static final boolean DEBUG = false;

	private final Selection mSelection = new Selection();		private final Selection mSelection = new Selection();

	// Only created when selection is cleared.		// Only created when selection is cleared.
	private Selection mIntermediateSelection;		private Selection mIntermediateSelection;

			private Ranger mRanger;
	private final List<MultiSelectManager.Callback> mCallbacks = new ArrayList<>(1);		private final List<MultiSelectManager.Callback> mCallbacks = new ArrayList<>(1);

	private Adapter<?> mAdapter;		private Adapter<?> mAdapter;
	@@ -213,6 +219,8 @@ public final class MultiSelectManager {
	* Clears the selection.		* Clears the selection.
	*/		*/
	public void clearSelection() {		public void clearSelection() {
			mRanger = null;

	if (mSelection.isEmpty()) {		if (mSelection.isEmpty()) {
	return;		return;
	}		}
	@@ -238,7 +246,7 @@ public final class MultiSelectManager {
	return false;		return false;
	}		}

	return onSingleTapUp(mHelper.findEventPosition(e));		return onSingleTapUp(mHelper.findEventPosition(e), e.getMetaState());
	}		}

	/**		/**
	@@ -246,11 +254,12 @@ public final class MultiSelectManager {
	* can be mocked.		* can be mocked.
	*		*
	* @param position		* @param position
			* @param metaState as returned from {@link MotionEvent#getMetaState()}.
	* @return true if the event was consumed.		* @return true if the event was consumed.
	* @hide		* @hide
	*/		*/
	@VisibleForTesting		@VisibleForTesting
	boolean onSingleTapUp(int position) {		boolean onSingleTapUp(int position, int metaState) {
	if (mSelection.isEmpty()) {		if (mSelection.isEmpty()) {
	return false;		return false;
	}		}
	@@ -261,10 +270,18 @@ public final class MultiSelectManager {
	return true;		return true;
	}		}

			if (isShiftPressed(metaState) && mRanger != null) {
			mRanger.snapSelection(position);
			} else {
	toggleSelection(position);		toggleSelection(position);
			}
	return true;		return true;
	}		}

			private static boolean isShiftPressed(int metaState) {
			return (metaState & KeyEvent.META_SHIFT_ON) != 0;
			}

	private void onLongPress(MotionEvent e) {		private void onLongPress(MotionEvent e) {
	if (DEBUG) Log.d(TAG, "Handling long press event.");		if (DEBUG) Log.d(TAG, "Handling long press event.");

	@@ -273,7 +290,7 @@ public final class MultiSelectManager {
	if (DEBUG) Log.i(TAG, "View is null. Cannot handle tap event.");		if (DEBUG) Log.i(TAG, "View is null. Cannot handle tap event.");
	}		}

	toggleSelection(position);		onLongPress(position);
	}		}

	/**		/**
	@@ -292,22 +309,87 @@ public final class MultiSelectManager {
	toggleSelection(position);		toggleSelection(position);
	}		}

	private void toggleSelection(int position) {		/**
			* Toggles the selection state at position. If an item does end up selected
			* a new Ranger (range selection manager) at that point is created.
			*
			* @param position
			* @return True if state changed.
			*/
			private boolean toggleSelection(int position) {
	// Position may be special "no position" during certain		// Position may be special "no position" during certain
	// transitional phases. If so, skip handling of the event.		// transitional phases. If so, skip handling of the event.
	if (position == RecyclerView.NO_POSITION) {		if (position == RecyclerView.NO_POSITION) {
	if (DEBUG) Log.d(TAG, "Ignoring toggle for element with no position.");		if (DEBUG) Log.d(TAG, "Ignoring toggle for element with no position.");
	return;		return false;
			}

			if (mSelection.contains(position)) {
			return attemptDeselect(position);
			} else {
			boolean selected = attemptSelect(position);
			// Here we're already in selection mode. In that case
			// When a simple click/tap (without SHIFT) creates causes
			// an item to be selected.
			// By recreating Ranger at this point, we allow the user to create
			// multiple separate contiguous ranges with SHIFT+Click & Click.
			if (selected) {
			mRanger = new Ranger(position);
			}
			return selected;
			}
			}

			/**
			* Try to select all elements in range. Not that callbacks can cancel selection
			* of specific items, so some or even all items may not reflect the desired
			* state after the update is complete.
			*
			* @param begin inclusive
			* @param end inclusive
			* @param selected
			*/
			private void updateRange(int begin, int end, boolean selected) {
			checkState(end >= begin);
			if (DEBUG) Log.i(TAG, String.format("Updating range begin=%d, end=%d, selected=%b.", begin, end, selected));
			for (int i = begin; i <= end; i++) {
			if (selected) {
			attemptSelect(i);
			} else {
			attemptDeselect(i);
			}
			}
			}

			/**
			* @param position
			* @return True if the update was applied.
			*/
			private boolean attemptSelect(int position) {
			if (notifyBeforeItemStateChange(position, true)) {
			mSelection.add(position);
			notifyItemStateChanged(position, true);
			if (DEBUG) Log.d(TAG, "Selection after select: " + mSelection);
			return true;
			} else {
			if (DEBUG) Log.d(TAG, "Select cancelled by listener.");
			return false;
			}
	}		}

	if (DEBUG) Log.d(TAG, "Handling long press on view: " + position);		/**
	boolean nextState = !mSelection.contains(position);		* @param position
	if (notifyBeforeItemStateChange(position, nextState)) {		* @return True if the update was applied.
	boolean selected = mSelection.flip(position);		*/
	notifyItemStateChanged(position, selected);		private boolean attemptDeselect(int position) {
	if (DEBUG) Log.d(TAG, "Selection after long press: " + mSelection);		if (notifyBeforeItemStateChange(position, false)) {
			mSelection.remove(position);
			notifyItemStateChanged(position, false);
			if (DEBUG) Log.d(TAG, "Selection after deselect: " + mSelection);
			return true;
	} else {		} else {
	Log.i(TAG, "Selection change cancelled by listener.");		if (DEBUG) Log.d(TAG, "Select cancelled by listener.");
			return false;
	}		}
	}		}

	@@ -335,6 +417,106 @@ public final class MultiSelectManager {
	mAdapter.notifyItemChanged(position);		mAdapter.notifyItemChanged(position);
	}		}

			/**
			* Class providing support for managing range selections.
			*/
			private final class Ranger {
			private static final int UNDEFINED = -1;

			final int mBegin;
			int mEnd = UNDEFINED;

			public Ranger(int begin) {
			if (DEBUG) Log.d(TAG, String.format("New Ranger(%d) created.", begin));
			mBegin = begin;
			}

			void snapSelection(int position) {
			checkState(mRanger != null);
			checkArgument(position != RecyclerView.NO_POSITION);

			if (mEnd == UNDEFINED \|\| mEnd == mBegin) {
			// Reset mEnd so it can be established in establishRange.
			mEnd = UNDEFINED;
			establishRange(position);
			} else {
			reviseRange(position);
			}
			}

			private void establishRange(int position) {
			checkState(mRanger.mEnd == UNDEFINED);

			if (position == mBegin) {
			mEnd = position;
			}

			if (position > mBegin) {
			updateRange(mBegin + 1, position, true);
			} else if (position < mBegin) {
			updateRange(position, mBegin - 1, true);
			}

			mEnd = position;
			}

			private void reviseRange(int position) {
			checkState(mEnd != UNDEFINED);
			checkState(mBegin != mEnd);

			if (position == mEnd) {
			if (DEBUG) Log.i(TAG, "Skipping no-op revision click on mEndRange.");
			}

			if (mEnd > mBegin) {
			reviseAscendingRange(position);
			} else if (mEnd < mBegin) {
			reviseDescendingRange(position);
			}
			// the "else" case is covered by checkState at beginning of method.

			mEnd = position;
			}

			/**
			* Updates an existing ascending seleciton.
			* @param position
			*/
			private void reviseAscendingRange(int position) {
			// Reducing or reversing the range....
			if (position < mEnd) {
			if (position < mBegin) {
			updateRange(mBegin + 1, mEnd, false);
			updateRange(position, mBegin -1, true);
			} else {
			updateRange(position + 1, mEnd, false);
			}
			}

			// Extending the range...
			else if (position > mEnd) {
			updateRange(mEnd + 1, position, true);
			}
			}

			private void reviseDescendingRange(int position) {
			// Reducing or reversing the range....
			if (position > mEnd) {
			if (position > mBegin) {
			updateRange(mEnd, mBegin - 1, false);
			updateRange(mBegin + 1, position, true);
			} else {
			updateRange(mEnd, position - 1, false);
			}
			}

			// Extending the range...
			else if (position < mEnd) {
			updateRange(position, mEnd - 1, true);
			}
			}
			}

	/**		/**
	* Object representing the current selection. Provides read only access		* Object representing the current selection. Provides read only access
	* public access, and private write access.		* public access, and private write access.

packages/DocumentsUI/tests/src/com/android/documentsui/MultiSelectManagerTest.java

+78 −8

Original line number	Original line	Diff line number	Diff line
	@@ -19,6 +19,7 @@ package com.android.documentsui;
	import static org.junit.Assert.*;		import static org.junit.Assert.*;

	import android.support.v7.widget.RecyclerView;		import android.support.v7.widget.RecyclerView;
			import android.view.KeyEvent;
	import android.view.MotionEvent;		import android.view.MotionEvent;
	import android.view.View;		import android.view.View;
	import android.view.ViewGroup;		import android.view.ViewGroup;
	@@ -78,34 +79,92 @@ public class MultiSelectManagerTest {

	@Test		@Test
	public void singleTapUp_DoesNotSelectBeforeLongPress() {		public void singleTapUp_DoesNotSelectBeforeLongPress() {
	mManager.onSingleTapUp(99);		mManager.onSingleTapUp(99, 0);
	assertSelection();		assertSelection();
	}		}

	@Test		@Test
	public void singleTapUp_UnselectsSelectedItem() {		public void singleTapUp_UnselectsSelectedItem() {
	mManager.onLongPress(7);		mManager.onLongPress(7);
	mManager.onSingleTapUp(7);		mManager.onSingleTapUp(7, 0);
	assertSelection();		assertSelection();
	}		}

	@Test		@Test
	public void singleTapUp_NoPositionClearsSelection() {		public void singleTapUp_NoPositionClearsSelection() {
	mManager.onLongPress(7);		mManager.onLongPress(7);
	mManager.onSingleTapUp(11);		mManager.onSingleTapUp(11, 0);
	mManager.onSingleTapUp(RecyclerView.NO_POSITION);		mManager.onSingleTapUp(RecyclerView.NO_POSITION, 0);
	assertSelection();		assertSelection();
	}		}

	@Test		@Test
	public void singleTapUp_ExtendsSelection() {		public void singleTapUp_ExtendsSelection() {
	mManager.onLongPress(99);		mManager.onLongPress(99);
	mManager.onSingleTapUp(7);		mManager.onSingleTapUp(7, 0);
	mManager.onSingleTapUp(13);		mManager.onSingleTapUp(13, 0);
	mManager.onSingleTapUp(129899);		mManager.onSingleTapUp(129899, 0);
	assertSelection(7, 99, 13, 129899);		assertSelection(7, 99, 13, 129899);
	}		}

			@Test
			public void singleTapUp_ShiftCreatesRangeSelection() {
			mManager.onLongPress(7);
			mManager.onSingleTapUp(17, KeyEvent.META_SHIFT_ON);
			assertRangeSelection(7, 17);
			}

			@Test
			public void singleTapUp_ShiftCreatesRangeSeletion_Backwards() {
			mManager.onLongPress(17);
			mManager.onSingleTapUp(7, KeyEvent.META_SHIFT_ON);
			assertRangeSelection(7, 17);
			}

			@Test
			public void singleTapUp_SecondShiftClickExtendsSelection() {
			mManager.onLongPress(7);
			mManager.onSingleTapUp(11, KeyEvent.META_SHIFT_ON);
			mManager.onSingleTapUp(17, KeyEvent.META_SHIFT_ON);
			assertRangeSelection(7, 17);
			}

			@Test
			public void singleTapUp_MultipleContiguousRangesSelected() {
			mManager.onLongPress(7);
			mManager.onSingleTapUp(11, KeyEvent.META_SHIFT_ON);
			mManager.onSingleTapUp(20, 0);
			mManager.onSingleTapUp(25, KeyEvent.META_SHIFT_ON);
			assertRangeSelected(7, 11);
			assertRangeSelected(20, 25);
			assertSelectionSize(11);
			}

			@Test
			public void singleTapUp_ShiftReducesSelectionRange_FromPreviousShiftClick() {
			mManager.onLongPress(7);
			mManager.onSingleTapUp(17, KeyEvent.META_SHIFT_ON);
			mManager.onSingleTapUp(10, KeyEvent.META_SHIFT_ON);
			assertRangeSelection(7, 10);
			}

			@Test
			public void singleTapUp_ShiftReducesSelectionRange_FromPreviousShiftClick_Backwards() {
			mManager.onLongPress(17);
			mManager.onSingleTapUp(7, KeyEvent.META_SHIFT_ON);
			mManager.onSingleTapUp(14, KeyEvent.META_SHIFT_ON);
			assertRangeSelection(14, 17);
			}


			@Test
			public void singleTapUp_ShiftReversesSelectionDirection() {
			mManager.onLongPress(7);
			mManager.onSingleTapUp(17, KeyEvent.META_SHIFT_ON);
			mManager.onSingleTapUp(0, KeyEvent.META_SHIFT_ON);
			assertRangeSelection(0, 7);
			}

	private void assertSelected(int... expected) {		private void assertSelected(int... expected) {
	for (int i = 0; i < expected.length; i++) {		for (int i = 0; i < expected.length; i++) {
	Selection selection = mManager.getSelection();		Selection selection = mManager.getSelection();
	@@ -120,9 +179,20 @@ public class MultiSelectManagerTest {
	assertSelected(expected);		assertSelected(expected);
	}		}

			private void assertRangeSelected(int begin, int end) {
			for (int i = begin; i <= end; i++) {
			assertSelected(i);
			}
			}

			private void assertRangeSelection(int begin, int end) {
			assertSelectionSize(end - begin + 1);
			assertRangeSelected(begin, end);
			}

	private void assertSelectionSize(int expected) {		private void assertSelectionSize(int expected) {
	Selection selection = mManager.getSelection();		Selection selection = mManager.getSelection();
	assertEquals(expected, selection.size());		assertEquals(selection.toString(), expected, selection.size());
	}		}

	private static final class EventHelper implements RecyclerViewHelper {		private static final class EventHelper implements RecyclerViewHelper {