1 /* 2 * Copyright (C) 2015 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.deskclock.data; 18 19 import android.content.SharedPreferences; 20 21 /** 22 * This class encapsulates the transfer of data between widget objects and their permanent storage 23 * in {@link SharedPreferences}. 24 */ 25 final class WidgetDAO { 26 27 /** Suffix for a key to a preference that stores the instance count for a given widget type. */ 28 private static final String WIDGET_COUNT = "_widget_count"; 29 WidgetDAO()30 private WidgetDAO() {} 31 32 /** 33 * @param widgetProviderClass indicates the type of widget being counted 34 * @param count the number of widgets of the given type 35 * @return the delta between the new count and the old count 36 */ updateWidgetCount(SharedPreferences prefs, Class widgetProviderClass, int count)37 static int updateWidgetCount(SharedPreferences prefs, Class widgetProviderClass, int count) { 38 final String key = widgetProviderClass.getSimpleName() + WIDGET_COUNT; 39 final int oldCount = prefs.getInt(key, 0); 40 if (count == 0) { 41 prefs.edit().remove(key).apply(); 42 } else { 43 prefs.edit().putInt(key, count).apply(); 44 } 45 return count - oldCount; 46 } 47 }