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 17package android.arch.paging.integration.testapp; 18 19import android.arch.paging.BoundedDataSource; 20import android.graphics.Color; 21import android.support.annotation.ColorInt; 22 23import java.util.ArrayList; 24import java.util.List; 25 26/** 27 * Sample data source with artificial data. 28 */ 29class ItemDataSource extends BoundedDataSource<Item> { 30 private static final int COUNT = 500; 31 32 @ColorInt 33 private static final int[] COLORS = new int[] { 34 Color.RED, 35 Color.BLUE, 36 Color.BLACK, 37 }; 38 39 private static int sGenerationId; 40 private final int mGenerationId = sGenerationId++; 41 42 @Override 43 public int countItems() { 44 return COUNT; 45 } 46 47 @Override 48 public List<Item> loadRange(int startPosition, int loadCount) { 49 if (isInvalid()) { 50 // abort! 51 return null; 52 } 53 54 List<Item> items = new ArrayList<>(); 55 int end = Math.min(COUNT, startPosition + loadCount); 56 int bgColor = COLORS[mGenerationId % COLORS.length]; 57 58 try { 59 Thread.sleep(1000); 60 } catch (InterruptedException e) { 61 e.printStackTrace(); 62 } 63 for (int i = startPosition; i != end; i++) { 64 items.add(new Item(i, "item " + i, bgColor)); 65 } 66 67 if (isInvalid()) { 68 // abort! 69 return null; 70 } 71 return items; 72 } 73} 74