1 /* 2 * Copyright 2018 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 17 package com.android.documentsui; 18 19 import android.os.Bundle; 20 21 import androidx.recyclerview.selection.MutableSelection; 22 import androidx.recyclerview.selection.Selection; 23 import androidx.recyclerview.selection.SelectionTracker; 24 import androidx.recyclerview.widget.RecyclerView.AdapterDataObserver; 25 26 import java.util.Set; 27 28 /** 29 * A stub SelectionTracker used by DocsSelectionHelper before a real SelectionTracker has been 30 * initialized by DirectoryFragment. 31 * @param <K> Selection key type which extends {@link SelectionTracker}. 32 */ 33 public class StubSelectionTracker<K> extends SelectionTracker<K> { 34 35 @Override addObserver(SelectionObserver observer)36 public void addObserver(SelectionObserver observer) { 37 } 38 39 @Override hasSelection()40 public boolean hasSelection() { 41 return false; 42 } 43 44 @Override getSelection()45 public Selection<K> getSelection() { 46 return new MutableSelection<K>(); 47 } 48 49 @Override copySelection(MutableSelection<K> dest)50 public void copySelection(MutableSelection<K> dest) { 51 } 52 53 @Override isSelected(K key)54 public boolean isSelected(K key) { 55 return false; 56 } 57 58 @Override restoreSelection(Selection<K> selection)59 public void restoreSelection(Selection<K> selection) { 60 } 61 62 @Override clearSelection()63 public boolean clearSelection() { 64 return false; 65 } 66 67 @Override setItemsSelected(Iterable<K> keys, boolean selected)68 public boolean setItemsSelected(Iterable<K> keys, boolean selected) { 69 return false; 70 } 71 72 @Override select(K key)73 public boolean select(K key) { 74 return false; 75 } 76 77 @Override deselect(K key)78 public boolean deselect(K key) { 79 return false; 80 } 81 82 @Override getAdapterDataObserver()83 protected AdapterDataObserver getAdapterDataObserver() { 84 return null; 85 } 86 87 @Override startRange(int position)88 public void startRange(int position) { 89 } 90 91 @Override extendRange(int position)92 public void extendRange(int position) { 93 } 94 95 @Override endRange()96 public void endRange() { 97 } 98 99 @Override isRangeActive()100 public boolean isRangeActive() { 101 return false; 102 } 103 104 @Override anchorRange(int position)105 public void anchorRange(int position) { 106 } 107 108 @Override extendProvisionalRange(int position)109 public void extendProvisionalRange(int position) { 110 } 111 112 @Override setProvisionalSelection(Set<K> newSelection)113 public void setProvisionalSelection(Set<K> newSelection) { 114 } 115 116 @Override clearProvisionalSelection()117 public void clearProvisionalSelection() { 118 } 119 120 @Override mergeProvisionalSelection()121 public void mergeProvisionalSelection() { 122 } 123 124 @Override onSaveInstanceState(Bundle state)125 public void onSaveInstanceState(Bundle state) { 126 } 127 128 @Override onRestoreInstanceState(Bundle state)129 public void onRestoreInstanceState(Bundle state) { 130 } 131 132 } 133