/* * Copyright (C) 2015 The Android Open Source Project * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package com.android.documentsui.selection; import static com.android.documentsui.base.Shared.DEBUG; import static com.android.documentsui.ui.ViewAutoScroller.NOT_SET; import android.graphics.Point; import android.graphics.Rect; import android.graphics.drawable.Drawable; import android.support.annotation.Nullable; import android.support.annotation.VisibleForTesting; import android.support.v7.widget.GridLayoutManager; import android.support.v7.widget.RecyclerView; import android.support.v7.widget.RecyclerView.OnScrollListener; import android.util.Log; import android.util.SparseArray; import android.util.SparseBooleanArray; import android.util.SparseIntArray; import android.view.View; import com.android.documentsui.DirectoryReloadLock; import com.android.documentsui.R; import com.android.documentsui.base.Events.InputEvent; import com.android.documentsui.dirlist.DocumentsAdapter; import com.android.documentsui.ui.ViewAutoScroller; import com.android.documentsui.ui.ViewAutoScroller.ScrollActionDelegate; import com.android.documentsui.ui.ViewAutoScroller.ScrollDistanceDelegate; import java.util.ArrayList; import java.util.Collections; import java.util.HashSet; import java.util.List; import java.util.Map; import java.util.Set; import java.util.function.IntPredicate; /** * Provides mouse driven band-select support when used in conjunction with {@link RecyclerView} * and {@link SelectionManager}. This class is responsible for rendering the band select * overlay and selecting overlaid items via SelectionManager. */ public class BandController extends OnScrollListener { private static final String TAG = "BandController"; private final Runnable mModelBuilder; private final SelectionEnvironment mEnvironment; private final DocumentsAdapter mAdapter; private final SelectionManager mSelectionManager; private final DirectoryReloadLock mLock; private final Runnable mViewScroller; private final GridModel.OnSelectionChangedListener mGridListener; @Nullable private Rect mBounds; @Nullable private Point mCurrentPosition; @Nullable private Point mOrigin; @Nullable private BandController.GridModel mModel; private Selection mSelection; public BandController( final RecyclerView view, DocumentsAdapter adapter, SelectionManager selectionManager, DirectoryReloadLock lock, IntPredicate gridItemTester) { this(new RuntimeSelectionEnvironment(view), adapter, selectionManager, lock, gridItemTester); } @VisibleForTesting BandController( SelectionEnvironment env, DocumentsAdapter adapter, SelectionManager selectionManager, DirectoryReloadLock lock, IntPredicate gridItemTester) { mLock = lock; selectionManager.bindContoller(this); mEnvironment = env; mAdapter = adapter; mSelectionManager = selectionManager; mEnvironment.addOnScrollListener(this); mViewScroller = new ViewAutoScroller( new ScrollDistanceDelegate() { @Override public Point getCurrentPosition() { return mCurrentPosition; } @Override public int getViewHeight() { return mEnvironment.getHeight(); } @Override public boolean isActive() { return BandController.this.isActive(); } }, env); mAdapter.registerAdapterDataObserver( new RecyclerView.AdapterDataObserver() { @Override public void onChanged() { if (isActive()) { endBandSelect(); } } @Override public void onItemRangeChanged( int startPosition, int itemCount, Object payload) { // No change in position. Ignoring. } @Override public void onItemRangeInserted(int startPosition, int itemCount) { if (isActive()) { endBandSelect(); } } @Override public void onItemRangeRemoved(int startPosition, int itemCount) { assert(startPosition >= 0); assert(itemCount > 0); // TODO: Should update grid model. } @Override public void onItemRangeMoved(int fromPosition, int toPosition, int itemCount) { throw new UnsupportedOperationException(); } }); mGridListener = new GridModel.OnSelectionChangedListener() { @Override public void onSelectionChanged(Set updatedSelection) { BandController.this.onSelectionChanged(updatedSelection); } @Override public boolean onBeforeItemStateChange(String id, boolean nextState) { return BandController.this.onBeforeItemStateChange(id, nextState); } }; mModelBuilder = new Runnable() { @Override public void run() { mModel = new GridModel(mEnvironment, gridItemTester, mAdapter); mModel.addOnSelectionChangedListener(mGridListener); } }; } @VisibleForTesting boolean isActive() { return mModel != null; } void bindSelection(Selection selection) { mSelection = selection; } public boolean onInterceptTouchEvent(InputEvent e) { if (shouldStart(e)) { if (!e.isCtrlKeyDown()) { mSelectionManager.clearSelection(); } startBandSelect(e.getOrigin()); } else if (shouldStop(e)) { endBandSelect(); } return isActive(); } /** * Handle a change in layout by cleaning up and getting rid of the old model and creating * a new model which will track the new layout. */ public void handleLayoutChanged() { if (mModel != null) { mModel.removeOnSelectionChangedListener(mGridListener); mModel.stopListening(); // build a new model, all fresh and happy. mModelBuilder.run(); } } public boolean shouldStart(InputEvent e) { // Don't start, or extend bands on non-left clicks. if (!e.isPrimaryButtonPressed()) { return false; } if (!e.isMouseEvent() && isActive()) { // Weird things happen if we keep up band select // when touch events happen. endBandSelect(); return false; } // b/30146357 && b/23793622. onInterceptTouchEvent does not dispatch events to onTouchEvent // unless the event is != ACTION_DOWN. Thus, we need to actually start band selection when // mouse moves, or else starting band selection on mouse down can cause problems as events // don't get routed correctly to onTouchEvent. return !isActive() && e.isActionMove() // the initial button move via mouse-touch (ie. down press) && mAdapter.hasModelIds() // we want to check against actual modelIds count to // avoid dummy view count from the AdapterWrapper && !e.isOverDragHotspot(); } public boolean shouldStop(InputEvent input) { return isActive() && input.isMouseEvent() && (input.isActionUp() || input.isMultiPointerActionUp() || input.isActionCancel()); } /** * Processes a MotionEvent by starting, ending, or resizing the band select overlay. * @param input */ public void onTouchEvent(InputEvent input) { assert(input.isMouseEvent()); if (shouldStop(input)) { endBandSelect(); return; } // We shouldn't get any events in this method when band select is not active, // but it turns some guests show up late to the party. // Probably happening when a re-layout is happening to the ReyclerView (ie. Pull-To-Refresh) if (!isActive()) { return; } assert(input.isActionMove()); mCurrentPosition = input.getOrigin(); mModel.resizeSelection(input.getOrigin()); scrollViewIfNecessary(); resizeBandSelectRectangle(); } /** * Starts band select by adding the drawable to the RecyclerView's overlay. */ private void startBandSelect(Point origin) { if (DEBUG) Log.d(TAG, "Starting band select @ " + origin); mLock.block(); mOrigin = origin; mModelBuilder.run(); // Creates a new selection model. mModel.startSelection(mOrigin); } /** * Scrolls the view if necessary. */ private void scrollViewIfNecessary() { mEnvironment.removeCallback(mViewScroller); mViewScroller.run(); mEnvironment.invalidateView(); } /** * Resizes the band select rectangle by using the origin and the current pointer position as * two opposite corners of the selection. */ private void resizeBandSelectRectangle() { mBounds = new Rect(Math.min(mOrigin.x, mCurrentPosition.x), Math.min(mOrigin.y, mCurrentPosition.y), Math.max(mOrigin.x, mCurrentPosition.x), Math.max(mOrigin.y, mCurrentPosition.y)); mEnvironment.showBand(mBounds); } /** * Ends band select by removing the overlay. */ private void endBandSelect() { if (DEBUG) Log.d(TAG, "Ending band select."); mEnvironment.hideBand(); mSelection.applyProvisionalSelection(); mModel.endSelection(); int firstSelected = mModel.getPositionNearestOrigin(); if (firstSelected != NOT_SET) { if (mSelection.contains(mAdapter.getModelId(firstSelected))) { // TODO: firstSelected should really be lastSelected, we want to anchor the item // where the mouse-up occurred. mSelectionManager.setSelectionRangeBegin(firstSelected); } else { // TODO: Check if this is really happening. Log.w(TAG, "First selected by band is NOT in selection!"); } } mModel = null; mOrigin = null; mLock.unblock(); } private void onSelectionChanged(Set updatedSelection) { Map delta = mSelection.setProvisionalSelection(updatedSelection); for (Map.Entry entry: delta.entrySet()) { mSelectionManager.notifyItemStateChanged(entry.getKey(), entry.getValue()); } mSelectionManager.notifySelectionChanged(); } private boolean onBeforeItemStateChange(String id, boolean nextState) { return mSelectionManager.canSetState(id, nextState); } @Override public void onScrolled(RecyclerView recyclerView, int dx, int dy) { if (!isActive()) { return; } // Adjust the y-coordinate of the origin the opposite number of pixels so that the // origin remains in the same place relative to the view's items. mOrigin.y -= dy; resizeBandSelectRectangle(); } /** * Provides a band selection item model for views within a RecyclerView. This class queries the * RecyclerView to determine where its items are placed; then, once band selection is underway, * it alerts listeners of which items are covered by the selections. */ @VisibleForTesting static final class GridModel extends RecyclerView.OnScrollListener { public static final int NOT_SET = -1; // Enum values used to determine the corner at which the origin is located within the private static final int UPPER = 0x00; private static final int LOWER = 0x01; private static final int LEFT = 0x00; private static final int RIGHT = 0x02; private static final int UPPER_LEFT = UPPER | LEFT; private static final int UPPER_RIGHT = UPPER | RIGHT; private static final int LOWER_LEFT = LOWER | LEFT; private static final int LOWER_RIGHT = LOWER | RIGHT; private final SelectionEnvironment mHelper; private final IntPredicate mGridItemTester; private final DocumentsAdapter mAdapter; private final List mOnSelectionChangedListeners = new ArrayList<>(); // Map from the x-value of the left side of a SparseBooleanArray of adapter positions, keyed // by their y-offset. For example, if the first column of the view starts at an x-value of 5, // mColumns.get(5) would return an array of positions in that column. Within that array, the // value for key y is the adapter position for the item whose y-offset is y. private final SparseArray mColumns = new SparseArray<>(); // List of limits along the x-axis (columns). // This list is sorted from furthest left to furthest right. private final List mColumnBounds = new ArrayList<>(); // List of limits along the y-axis (rows). Note that this list only contains items which // have been in the viewport. private final List mRowBounds = new ArrayList<>(); // The adapter positions which have been recorded so far. private final SparseBooleanArray mKnownPositions = new SparseBooleanArray(); // Array passed to registered OnSelectionChangedListeners. One array is created and reused // throughout the lifetime of the object. private final Set mSelection = new HashSet<>(); // The current pointer (in absolute positioning from the top of the view). private Point mPointer = null; // The bounds of the band selection. private RelativePoint mRelativeOrigin; private RelativePoint mRelativePointer; private boolean mIsActive; // Tracks where the band select originated from. This is used to determine where selections // should expand from when Shift+click is used. private int mPositionNearestOrigin = NOT_SET; GridModel(SelectionEnvironment helper, IntPredicate gridItemTester, DocumentsAdapter adapter) { mHelper = helper; mAdapter = adapter; mGridItemTester = gridItemTester; mHelper.addOnScrollListener(this); } /** * Stops listening to the view's scrolls. Call this function before discarding a * BandSelecModel object to prevent memory leaks. */ void stopListening() { mHelper.removeOnScrollListener(this); } /** * Start a band select operation at the given point. * @param relativeOrigin The origin of the band select operation, relative to the viewport. * For example, if the view is scrolled to the bottom, the top-left of the viewport * would have a relative origin of (0, 0), even though its absolute point has a higher * y-value. */ void startSelection(Point relativeOrigin) { recordVisibleChildren(); if (isEmpty()) { // The selection band logic works only if there is at least one visible child. return; } mIsActive = true; mPointer = mHelper.createAbsolutePoint(relativeOrigin); mRelativeOrigin = new RelativePoint(mPointer); mRelativePointer = new RelativePoint(mPointer); computeCurrentSelection(); notifyListeners(); } /** * Resizes the selection by adjusting the pointer (i.e., the corner of the selection * opposite the origin. * @param relativePointer The pointer (opposite of the origin) of the band select operation, * relative to the viewport. For example, if the view is scrolled to the bottom, the * top-left of the viewport would have a relative origin of (0, 0), even though its * absolute point has a higher y-value. */ @VisibleForTesting void resizeSelection(Point relativePointer) { mPointer = mHelper.createAbsolutePoint(relativePointer); updateModel(); } /** * Ends the band selection. */ void endSelection() { mIsActive = false; } /** * @return The adapter position for the item nearest the origin corresponding to the latest * band select operation, or NOT_SET if the selection did not cover any items. */ int getPositionNearestOrigin() { return mPositionNearestOrigin; } @Override public void onScrolled(RecyclerView recyclerView, int dx, int dy) { if (!mIsActive) { return; } mPointer.x += dx; mPointer.y += dy; recordVisibleChildren(); updateModel(); } /** * Queries the view for all children and records their location metadata. */ private void recordVisibleChildren() { for (int i = 0; i < mHelper.getVisibleChildCount(); i++) { int adapterPosition = mHelper.getAdapterPositionAt(i); // Sometimes the view is not attached, as we notify the multi selection manager // synchronously, while views are attached asynchronously. As a result items which // are in the adapter may not actually have a corresponding view (yet). if (mHelper.hasView(adapterPosition) && mGridItemTester.test(adapterPosition) && !mKnownPositions.get(adapterPosition)) { mKnownPositions.put(adapterPosition, true); recordItemData(mHelper.getAbsoluteRectForChildViewAt(i), adapterPosition); } } } /** * Checks if there are any recorded children. */ private boolean isEmpty() { return mColumnBounds.size() == 0 || mRowBounds.size() == 0; } /** * Updates the limits lists and column map with the given item metadata. * @param absoluteChildRect The absolute rectangle for the child view being processed. * @param adapterPosition The position of the child view being processed. */ private void recordItemData(Rect absoluteChildRect, int adapterPosition) { if (mColumnBounds.size() != mHelper.getColumnCount()) { // If not all x-limits have been recorded, record this one. recordLimits( mColumnBounds, new Limits(absoluteChildRect.left, absoluteChildRect.right)); } recordLimits(mRowBounds, new Limits(absoluteChildRect.top, absoluteChildRect.bottom)); SparseIntArray columnList = mColumns.get(absoluteChildRect.left); if (columnList == null) { columnList = new SparseIntArray(); mColumns.put(absoluteChildRect.left, columnList); } columnList.put(absoluteChildRect.top, adapterPosition); } /** * Ensures limits exists within the sorted list limitsList, and adds it to the list if it * does not exist. */ private void recordLimits(List limitsList, GridModel.Limits limits) { int index = Collections.binarySearch(limitsList, limits); if (index < 0) { limitsList.add(~index, limits); } } /** * Handles a moved pointer; this function determines whether the pointer movement resulted * in a selection change and, if it has, notifies listeners of this change. */ private void updateModel() { RelativePoint old = mRelativePointer; mRelativePointer = new RelativePoint(mPointer); if (old != null && mRelativePointer.equals(old)) { return; } computeCurrentSelection(); notifyListeners(); } /** * Computes the currently-selected items. */ private void computeCurrentSelection() { if (areItemsCoveredByBand(mRelativePointer, mRelativeOrigin)) { updateSelection(computeBounds()); } else { mSelection.clear(); mPositionNearestOrigin = NOT_SET; } } /** * Notifies all listeners of a selection change. Note that this function simply passes * mSelection, so computeCurrentSelection() should be called before this * function. */ private void notifyListeners() { for (GridModel.OnSelectionChangedListener listener : mOnSelectionChangedListeners) { listener.onSelectionChanged(mSelection); } } /** * @param rect Rectangle including all covered items. */ private void updateSelection(Rect rect) { int columnStart = Collections.binarySearch(mColumnBounds, new Limits(rect.left, rect.left)); assert(columnStart >= 0); int columnEnd = columnStart; for (int i = columnStart; i < mColumnBounds.size() && mColumnBounds.get(i).lowerLimit <= rect.right; i++) { columnEnd = i; } int rowStart = Collections.binarySearch(mRowBounds, new Limits(rect.top, rect.top)); if (rowStart < 0) { mPositionNearestOrigin = NOT_SET; return; } int rowEnd = rowStart; for (int i = rowStart; i < mRowBounds.size() && mRowBounds.get(i).lowerLimit <= rect.bottom; i++) { rowEnd = i; } updateSelection(columnStart, columnEnd, rowStart, rowEnd); } /** * Computes the selection given the previously-computed start- and end-indices for each * row and column. */ private void updateSelection( int columnStartIndex, int columnEndIndex, int rowStartIndex, int rowEndIndex) { if (DEBUG) Log.d(TAG, String.format("updateSelection: %d, %d, %d, %d", columnStartIndex, columnEndIndex, rowStartIndex, rowEndIndex)); mSelection.clear(); for (int column = columnStartIndex; column <= columnEndIndex; column++) { SparseIntArray items = mColumns.get(mColumnBounds.get(column).lowerLimit); for (int row = rowStartIndex; row <= rowEndIndex; row++) { // The default return value for SparseIntArray.get is 0, which is a valid // position. Use a sentry value to prevent erroneously selecting item 0. final int rowKey = mRowBounds.get(row).lowerLimit; int position = items.get(rowKey, NOT_SET); if (position != NOT_SET) { String id = mAdapter.getModelId(position); if (id != null) { // The adapter inserts items for UI layout purposes that aren't associated // with files. Those will have a null model ID. Don't select them. if (canSelect(id)) { mSelection.add(id); } } if (isPossiblePositionNearestOrigin(column, columnStartIndex, columnEndIndex, row, rowStartIndex, rowEndIndex)) { // If this is the position nearest the origin, record it now so that it // can be returned by endSelection() later. mPositionNearestOrigin = position; } } } } } /** * @return True if the item is selectable. */ private boolean canSelect(String id) { // TODO: Simplify the logic, so the check whether we can select is done in one place. // Consider injecting ActivityConfig, or move the checks from MultiSelectManager to // Selection. for (GridModel.OnSelectionChangedListener listener : mOnSelectionChangedListeners) { if (!listener.onBeforeItemStateChange(id, true)) { return false; } } return true; } /** * @return Returns true if the position is the nearest to the origin, or, in the case of the * lower-right corner, whether it is possible that the position is the nearest to the * origin. See comment below for reasoning for this special case. */ private boolean isPossiblePositionNearestOrigin(int columnIndex, int columnStartIndex, int columnEndIndex, int rowIndex, int rowStartIndex, int rowEndIndex) { int corner = computeCornerNearestOrigin(); switch (corner) { case UPPER_LEFT: return columnIndex == columnStartIndex && rowIndex == rowStartIndex; case UPPER_RIGHT: return columnIndex == columnEndIndex && rowIndex == rowStartIndex; case LOWER_LEFT: return columnIndex == columnStartIndex && rowIndex == rowEndIndex; case LOWER_RIGHT: // Note that in some cases, the last row will not have as many items as there // are columns (e.g., if there are 4 items and 3 columns, the second row will // only have one item in the first column). This function is invoked for each // position from left to right, so return true for any position in the bottom // row and only the right-most position in the bottom row will be recorded. return rowIndex == rowEndIndex; default: throw new RuntimeException("Invalid corner type."); } } /** * Listener for changes in which items have been band selected. */ static interface OnSelectionChangedListener { public void onSelectionChanged(Set updatedSelection); public boolean onBeforeItemStateChange(String id, boolean nextState); } void addOnSelectionChangedListener(GridModel.OnSelectionChangedListener listener) { mOnSelectionChangedListeners.add(listener); } void removeOnSelectionChangedListener(GridModel.OnSelectionChangedListener listener) { mOnSelectionChangedListeners.remove(listener); } /** * Limits of a view item. For example, if an item's left side is at x-value 5 and its right side * is at x-value 10, the limits would be from 5 to 10. Used to record the left- and right sides * of item columns and the top- and bottom sides of item rows so that it can be determined * whether the pointer is located within the bounds of an item. */ private static class Limits implements Comparable { int lowerLimit; int upperLimit; Limits(int lowerLimit, int upperLimit) { this.lowerLimit = lowerLimit; this.upperLimit = upperLimit; } @Override public int compareTo(GridModel.Limits other) { return lowerLimit - other.lowerLimit; } @Override public boolean equals(Object other) { if (!(other instanceof GridModel.Limits)) { return false; } return ((GridModel.Limits) other).lowerLimit == lowerLimit && ((GridModel.Limits) other).upperLimit == upperLimit; } @Override public String toString() { return "(" + lowerLimit + ", " + upperLimit + ")"; } } /** * The location of a coordinate relative to items. This class represents a general area of the * view as it relates to band selection rather than an explicit point. For example, two * different points within an item are considered to have the same "location" because band * selection originating within the item would select the same items no matter which point * was used. Same goes for points between items as well as those at the very beginning or end * of the view. * * Tracking a coordinate (e.g., an x-value) as a CoordinateLocation instead of as an int has the * advantage of tying the value to the Limits of items along that axis. This allows easy * selection of items within those Limits as opposed to a search through every item to see if a * given coordinate value falls within those Limits. */ private static class RelativeCoordinate implements Comparable { /** * Location describing points after the last known item. */ static final int AFTER_LAST_ITEM = 0; /** * Location describing points before the first known item. */ static final int BEFORE_FIRST_ITEM = 1; /** * Location describing points between two items. */ static final int BETWEEN_TWO_ITEMS = 2; /** * Location describing points within the limits of one item. */ static final int WITHIN_LIMITS = 3; /** * The type of this coordinate, which is one of AFTER_LAST_ITEM, BEFORE_FIRST_ITEM, * BETWEEN_TWO_ITEMS, or WITHIN_LIMITS. */ final int type; /** * The limits before the coordinate; only populated when type == WITHIN_LIMITS or type == * BETWEEN_TWO_ITEMS. */ GridModel.Limits limitsBeforeCoordinate; /** * The limits after the coordinate; only populated when type == BETWEEN_TWO_ITEMS. */ GridModel.Limits limitsAfterCoordinate; // Limits of the first known item; only populated when type == BEFORE_FIRST_ITEM. GridModel.Limits mFirstKnownItem; // Limits of the last known item; only populated when type == AFTER_LAST_ITEM. GridModel.Limits mLastKnownItem; /** * @param limitsList The sorted limits list for the coordinate type. If this * CoordinateLocation is an x-value, mXLimitsList should be passed; otherwise, * mYLimitsList should be pased. * @param value The coordinate value. */ RelativeCoordinate(List limitsList, int value) { int index = Collections.binarySearch(limitsList, new Limits(value, value)); if (index >= 0) { this.type = WITHIN_LIMITS; this.limitsBeforeCoordinate = limitsList.get(index); } else if (~index == 0) { this.type = BEFORE_FIRST_ITEM; this.mFirstKnownItem = limitsList.get(0); } else if (~index == limitsList.size()) { GridModel.Limits lastLimits = limitsList.get(limitsList.size() - 1); if (lastLimits.lowerLimit <= value && value <= lastLimits.upperLimit) { this.type = WITHIN_LIMITS; this.limitsBeforeCoordinate = lastLimits; } else { this.type = AFTER_LAST_ITEM; this.mLastKnownItem = lastLimits; } } else { GridModel.Limits limitsBeforeIndex = limitsList.get(~index - 1); if (limitsBeforeIndex.lowerLimit <= value && value <= limitsBeforeIndex.upperLimit) { this.type = WITHIN_LIMITS; this.limitsBeforeCoordinate = limitsList.get(~index - 1); } else { this.type = BETWEEN_TWO_ITEMS; this.limitsBeforeCoordinate = limitsList.get(~index - 1); this.limitsAfterCoordinate = limitsList.get(~index); } } } int toComparisonValue() { if (type == BEFORE_FIRST_ITEM) { return mFirstKnownItem.lowerLimit - 1; } else if (type == AFTER_LAST_ITEM) { return mLastKnownItem.upperLimit + 1; } else if (type == BETWEEN_TWO_ITEMS) { return limitsBeforeCoordinate.upperLimit + 1; } else { return limitsBeforeCoordinate.lowerLimit; } } @Override public boolean equals(Object other) { if (!(other instanceof GridModel.RelativeCoordinate)) { return false; } GridModel.RelativeCoordinate otherCoordinate = (GridModel.RelativeCoordinate) other; return toComparisonValue() == otherCoordinate.toComparisonValue(); } @Override public int compareTo(GridModel.RelativeCoordinate other) { return toComparisonValue() - other.toComparisonValue(); } } /** * The location of a point relative to the Limits of nearby items; consists of both an x- and * y-RelativeCoordinateLocation. */ private class RelativePoint { final GridModel.RelativeCoordinate xLocation; final GridModel.RelativeCoordinate yLocation; RelativePoint(Point point) { this.xLocation = new RelativeCoordinate(mColumnBounds, point.x); this.yLocation = new RelativeCoordinate(mRowBounds, point.y); } @Override public boolean equals(Object other) { if (!(other instanceof RelativePoint)) { return false; } RelativePoint otherPoint = (RelativePoint) other; return xLocation.equals(otherPoint.xLocation) && yLocation.equals(otherPoint.yLocation); } } /** * Generates a rectangle which contains the items selected by the pointer and origin. * @return The rectangle, or null if no items were selected. */ private Rect computeBounds() { Rect rect = new Rect(); rect.left = getCoordinateValue( min(mRelativeOrigin.xLocation, mRelativePointer.xLocation), mColumnBounds, true); rect.right = getCoordinateValue( max(mRelativeOrigin.xLocation, mRelativePointer.xLocation), mColumnBounds, false); rect.top = getCoordinateValue( min(mRelativeOrigin.yLocation, mRelativePointer.yLocation), mRowBounds, true); rect.bottom = getCoordinateValue( max(mRelativeOrigin.yLocation, mRelativePointer.yLocation), mRowBounds, false); return rect; } /** * Computes the corner of the selection nearest the origin. * @return */ private int computeCornerNearestOrigin() { int cornerValue = 0; if (mRelativeOrigin.yLocation == min(mRelativeOrigin.yLocation, mRelativePointer.yLocation)) { cornerValue |= UPPER; } else { cornerValue |= LOWER; } if (mRelativeOrigin.xLocation == min(mRelativeOrigin.xLocation, mRelativePointer.xLocation)) { cornerValue |= LEFT; } else { cornerValue |= RIGHT; } return cornerValue; } private GridModel.RelativeCoordinate min(GridModel.RelativeCoordinate first, GridModel.RelativeCoordinate second) { return first.compareTo(second) < 0 ? first : second; } private GridModel.RelativeCoordinate max(GridModel.RelativeCoordinate first, GridModel.RelativeCoordinate second) { return first.compareTo(second) > 0 ? first : second; } /** * @return The absolute coordinate (i.e., the x- or y-value) of the given relative * coordinate. */ private int getCoordinateValue(GridModel.RelativeCoordinate coordinate, List limitsList, boolean isStartOfRange) { switch (coordinate.type) { case RelativeCoordinate.BEFORE_FIRST_ITEM: return limitsList.get(0).lowerLimit; case RelativeCoordinate.AFTER_LAST_ITEM: return limitsList.get(limitsList.size() - 1).upperLimit; case RelativeCoordinate.BETWEEN_TWO_ITEMS: if (isStartOfRange) { return coordinate.limitsAfterCoordinate.lowerLimit; } else { return coordinate.limitsBeforeCoordinate.upperLimit; } case RelativeCoordinate.WITHIN_LIMITS: return coordinate.limitsBeforeCoordinate.lowerLimit; } throw new RuntimeException("Invalid coordinate value."); } private boolean areItemsCoveredByBand( RelativePoint first, RelativePoint second) { return doesCoordinateLocationCoverItems(first.xLocation, second.xLocation) && doesCoordinateLocationCoverItems(first.yLocation, second.yLocation); } private boolean doesCoordinateLocationCoverItems( GridModel.RelativeCoordinate pointerCoordinate, GridModel.RelativeCoordinate originCoordinate) { if (pointerCoordinate.type == RelativeCoordinate.BEFORE_FIRST_ITEM && originCoordinate.type == RelativeCoordinate.BEFORE_FIRST_ITEM) { return false; } if (pointerCoordinate.type == RelativeCoordinate.AFTER_LAST_ITEM && originCoordinate.type == RelativeCoordinate.AFTER_LAST_ITEM) { return false; } if (pointerCoordinate.type == RelativeCoordinate.BETWEEN_TWO_ITEMS && originCoordinate.type == RelativeCoordinate.BETWEEN_TWO_ITEMS && pointerCoordinate.limitsBeforeCoordinate.equals( originCoordinate.limitsBeforeCoordinate) && pointerCoordinate.limitsAfterCoordinate.equals( originCoordinate.limitsAfterCoordinate)) { return false; } return true; } } /** * Provides functionality for BandController. Exists primarily to tests that are * fully isolated from RecyclerView. */ interface SelectionEnvironment extends ScrollActionDelegate { void showBand(Rect rect); void hideBand(); void addOnScrollListener(RecyclerView.OnScrollListener listener); void removeOnScrollListener(RecyclerView.OnScrollListener listener); int getHeight(); void invalidateView(); Point createAbsolutePoint(Point relativePoint); Rect getAbsoluteRectForChildViewAt(int index); int getAdapterPositionAt(int index); int getColumnCount(); int getChildCount(); int getVisibleChildCount(); /** * Items may be in the adapter, but without an attached view. */ boolean hasView(int adapterPosition); } /** Recycler view facade implementation backed by good ol' RecyclerView. */ private static final class RuntimeSelectionEnvironment implements SelectionEnvironment { private final RecyclerView mView; private final Drawable mBand; private boolean mIsOverlayShown = false; RuntimeSelectionEnvironment(RecyclerView view) { mView = view; mBand = mView.getContext().getTheme().getDrawable(R.drawable.band_select_overlay); } @Override public int getAdapterPositionAt(int index) { return mView.getChildAdapterPosition(mView.getChildAt(index)); } @Override public void addOnScrollListener(RecyclerView.OnScrollListener listener) { mView.addOnScrollListener(listener); } @Override public void removeOnScrollListener(RecyclerView.OnScrollListener listener) { mView.removeOnScrollListener(listener); } @Override public Point createAbsolutePoint(Point relativePoint) { return new Point(relativePoint.x + mView.computeHorizontalScrollOffset(), relativePoint.y + mView.computeVerticalScrollOffset()); } @Override public Rect getAbsoluteRectForChildViewAt(int index) { final View child = mView.getChildAt(index); final Rect childRect = new Rect(); child.getHitRect(childRect); childRect.left += mView.computeHorizontalScrollOffset(); childRect.right += mView.computeHorizontalScrollOffset(); childRect.top += mView.computeVerticalScrollOffset(); childRect.bottom += mView.computeVerticalScrollOffset(); return childRect; } @Override public int getChildCount() { return mView.getAdapter().getItemCount(); } @Override public int getVisibleChildCount() { return mView.getChildCount(); } @Override public int getColumnCount() { RecyclerView.LayoutManager layoutManager = mView.getLayoutManager(); if (layoutManager instanceof GridLayoutManager) { return ((GridLayoutManager) layoutManager).getSpanCount(); } // Otherwise, it is a list with 1 column. return 1; } @Override public int getHeight() { return mView.getHeight(); } @Override public void invalidateView() { mView.invalidate(); } @Override public void runAtNextFrame(Runnable r) { mView.postOnAnimation(r); } @Override public void removeCallback(Runnable r) { mView.removeCallbacks(r); } @Override public void scrollBy(int dy) { mView.scrollBy(0, dy); } @Override public void showBand(Rect rect) { mBand.setBounds(rect); if (!mIsOverlayShown) { mView.getOverlay().add(mBand); } } @Override public void hideBand() { mView.getOverlay().remove(mBand); } @Override public boolean hasView(int pos) { return mView.findViewHolderForAdapterPosition(pos) != null; } } }