1 /* 2 * Copyright (C) 2017 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 package com.android.documentsui.selection; 17 18 import static com.android.documentsui.base.SharedMinimal.DEBUG; 19 20 import android.support.v7.widget.RecyclerView; 21 import android.util.Log; 22 import android.view.MotionEvent; 23 24 import com.android.documentsui.selection.ItemDetailsLookup.ItemDetails; 25 import com.android.documentsui.selection.SelectionHelper.SelectionPredicate; 26 27 /** 28 * A MotionInputHandler that provides the high-level glue for touch driven selection. This class 29 * works with {@link RecyclerView}, {@link GestureRouter}, and {@link GestureSelectionHelper} to 30 * provide robust user drive selection support. 31 */ 32 public final class TouchInputHandler extends MotionInputHandler { 33 private static final String TAG = "TouchInputDelegate"; 34 35 private final SelectionPredicate mSelectionPredicate; 36 private final Callbacks mCallbacks; 37 private final Runnable mGestureKicker; 38 TouchInputHandler( SelectionHelper selectionHelper, ItemDetailsLookup detailsLookup, SelectionPredicate selectionPredicate, Runnable gestureKicker, Callbacks callbacks)39 public TouchInputHandler( 40 SelectionHelper selectionHelper, 41 ItemDetailsLookup detailsLookup, 42 SelectionPredicate selectionPredicate, 43 Runnable gestureKicker, 44 Callbacks callbacks) { 45 46 super(selectionHelper, detailsLookup, callbacks); 47 48 mSelectionPredicate = selectionPredicate; 49 mGestureKicker = gestureKicker; 50 mCallbacks = callbacks; 51 } 52 TouchInputHandler( SelectionHelper selectionHelper, ItemDetailsLookup detailsLookup, SelectionPredicate selectionPredicate, GestureSelectionHelper gestureHelper, Callbacks callbacks)53 public TouchInputHandler( 54 SelectionHelper selectionHelper, 55 ItemDetailsLookup detailsLookup, 56 SelectionPredicate selectionPredicate, 57 GestureSelectionHelper gestureHelper, 58 Callbacks callbacks) { 59 60 this( 61 selectionHelper, 62 detailsLookup, 63 selectionPredicate, 64 new Runnable() { 65 @Override 66 public void run() { 67 gestureHelper.start(); 68 } 69 }, 70 callbacks); 71 } 72 73 @Override onSingleTapUp(MotionEvent e)74 public boolean onSingleTapUp(MotionEvent e) { 75 if (!mDetailsLookup.overStableItem(e)) { 76 if (DEBUG) Log.d(TAG, "Tap not associated w/ model item. Clearing selection."); 77 mSelectionHelper.clearSelection(); 78 return false; 79 } 80 81 ItemDetails item = mDetailsLookup.getItemDetails(e); 82 if (mSelectionHelper.hasSelection()) { 83 if (isRangeExtension(e)) { 84 extendSelectionRange(item); 85 } else if (mSelectionHelper.isSelected(item.getStableId())) { 86 mSelectionHelper.deselect(item.getStableId()); 87 } else { 88 selectItem(item); 89 } 90 91 return true; 92 } 93 94 // Touch events select if they occur in the selection hotspot, 95 // otherwise they activate. 96 return item.inSelectionHotspot(e) 97 ? selectItem(item) 98 : mCallbacks.onItemActivated(item, e); 99 } 100 101 @Override onLongPress(MotionEvent e)102 public final void onLongPress(MotionEvent e) { 103 if (!mDetailsLookup.overStableItem(e)) { 104 if (DEBUG) Log.d(TAG, "Ignoring LongPress on non-model-backed item."); 105 return; 106 } 107 108 ItemDetails item = mDetailsLookup.getItemDetails(e); 109 boolean handled = false; 110 111 if (isRangeExtension(e)) { 112 extendSelectionRange(item); 113 handled = true; 114 } else { 115 if (!mSelectionHelper.isSelected(item.getStableId()) 116 && mSelectionPredicate.canSetStateForId(item.getStableId(), true)) { 117 // If we cannot select it, we didn't apply anchoring - therefore should not 118 // start gesture selection 119 if (selectItem(item)) { 120 // And finally if the item was selected && we can select multiple 121 // we kick off gesture selection. 122 if (mSelectionPredicate.canSelectMultiple()) { 123 mGestureKicker.run(); 124 } 125 handled = true; 126 } 127 } else { 128 // We only initiate drag and drop on long press for touch to allow regular 129 // touch-based scrolling 130 // mTouchDragListener.accept(e); 131 mCallbacks.onDragInitiated(e); 132 handled = true; 133 } 134 } 135 136 if (handled) { 137 mCallbacks.onPerformHapticFeedback(); 138 } 139 } 140 141 public static abstract class Callbacks extends MotionInputHandler.Callbacks { onItemActivated(ItemDetails item, MotionEvent e)142 public abstract boolean onItemActivated(ItemDetails item, MotionEvent e); onDragInitiated(MotionEvent e)143 public boolean onDragInitiated(MotionEvent e) { 144 return false; 145 } 146 } 147 } 148