The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame^] | 1 | /* |
| 2 | * Copyright (C) 2007 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 android.widget; |
| 18 | |
| 19 | import android.database.DataSetObservable; |
| 20 | import android.database.DataSetObserver; |
| 21 | import android.view.KeyEvent; |
| 22 | |
| 23 | /** |
| 24 | * Base class for a {@link ExpandableListAdapter} used to provide data and Views |
| 25 | * from some data to an expandable list view. |
| 26 | * <p> |
| 27 | * Adapters inheriting this class should verify that the base implementations of |
| 28 | * {@link #getCombinedChildId(long, long)} and {@link #getCombinedGroupId(long)} |
| 29 | * are correct in generating unique IDs from the group/children IDs. |
| 30 | * <p> |
| 31 | * @see SimpleExpandableListAdapter |
| 32 | * @see SimpleCursorTreeAdapter |
| 33 | */ |
| 34 | public abstract class BaseExpandableListAdapter implements ExpandableListAdapter { |
| 35 | private final DataSetObservable mDataSetObservable = new DataSetObservable(); |
| 36 | |
| 37 | public void registerDataSetObserver(DataSetObserver observer) { |
| 38 | mDataSetObservable.registerObserver(observer); |
| 39 | } |
| 40 | |
| 41 | public void unregisterDataSetObserver(DataSetObserver observer) { |
| 42 | mDataSetObservable.unregisterObserver(observer); |
| 43 | } |
| 44 | |
| 45 | /** |
| 46 | * {@see DataSetObservable#notifyInvalidated()} |
| 47 | */ |
| 48 | public void notifyDataSetInvalidated() { |
| 49 | mDataSetObservable.notifyInvalidated(); |
| 50 | } |
| 51 | |
| 52 | /** |
| 53 | * {@see DataSetObservable#notifyChanged()} |
| 54 | */ |
| 55 | public void notifyDataSetChanged() { |
| 56 | mDataSetObservable.notifyChanged(); |
| 57 | } |
| 58 | |
| 59 | public boolean areAllItemsEnabled() { |
| 60 | return true; |
| 61 | } |
| 62 | |
| 63 | public void onGroupCollapsed(int groupPosition) { |
| 64 | } |
| 65 | |
| 66 | public void onGroupExpanded(int groupPosition) { |
| 67 | } |
| 68 | |
| 69 | /** |
| 70 | * Override this method if you foresee a clash in IDs based on this scheme: |
| 71 | * <p> |
| 72 | * Base implementation returns a long: |
| 73 | * <li> bit 0: Whether this ID points to a child (unset) or group (set), so for this method |
| 74 | * this bit will be 1. |
| 75 | * <li> bit 1-31: Lower 31 bits of the groupId |
| 76 | * <li> bit 32-63: Lower 32 bits of the childId. |
| 77 | * <p> |
| 78 | * {@inheritDoc} |
| 79 | */ |
| 80 | public long getCombinedChildId(long groupId, long childId) { |
| 81 | return 0x8000000000000000L | ((groupId & 0x7FFFFFFF) << 32) | (childId & 0xFFFFFFFF); |
| 82 | } |
| 83 | |
| 84 | /** |
| 85 | * Override this method if you foresee a clash in IDs based on this scheme: |
| 86 | * <p> |
| 87 | * Base implementation returns a long: |
| 88 | * <li> bit 0: Whether this ID points to a child (unset) or group (set), so for this method |
| 89 | * this bit will be 0. |
| 90 | * <li> bit 1-31: Lower 31 bits of the groupId |
| 91 | * <li> bit 32-63: Lower 32 bits of the childId. |
| 92 | * <p> |
| 93 | * {@inheritDoc} |
| 94 | */ |
| 95 | public long getCombinedGroupId(long groupId) { |
| 96 | return (groupId & 0x7FFFFFFF) << 32; |
| 97 | } |
| 98 | |
| 99 | /** |
| 100 | * {@inheritDoc} |
| 101 | */ |
| 102 | public boolean isEmpty() { |
| 103 | return getGroupCount() == 0; |
| 104 | } |
| 105 | |
| 106 | } |