| /* |
| * Copyright (C) 2017 The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| package android.arch.paging.integration.testapp; |
| |
| import android.arch.paging.PositionalDataSource; |
| import android.graphics.Color; |
| import android.support.annotation.ColorInt; |
| import android.support.annotation.NonNull; |
| |
| import java.util.ArrayList; |
| import java.util.List; |
| |
| /** |
| * Sample data source with artificial data. |
| */ |
| class ItemDataSource extends PositionalDataSource<Item> { |
| private static final int COUNT = 500; |
| |
| @ColorInt |
| private static final int[] COLORS = new int[] { |
| Color.RED, |
| Color.BLUE, |
| Color.BLACK, |
| }; |
| |
| private static int sGenerationId; |
| private final int mGenerationId = sGenerationId++; |
| |
| private List<Item> loadRangeInternal(int startPosition, int loadCount) { |
| List<Item> items = new ArrayList<>(); |
| int end = Math.min(COUNT, startPosition + loadCount); |
| int bgColor = COLORS[mGenerationId % COLORS.length]; |
| |
| try { |
| Thread.sleep(1000); |
| } catch (InterruptedException e) { |
| e.printStackTrace(); |
| } |
| for (int i = startPosition; i != end; i++) { |
| items.add(new Item(i, "item " + i, bgColor)); |
| } |
| return items; |
| } |
| |
| @Override |
| public void loadInitial(@NonNull LoadInitialParams params, |
| @NonNull LoadInitialCallback<Item> callback) { |
| int position = computeInitialLoadPosition(params, COUNT); |
| int loadSize = computeInitialLoadSize(params, position, COUNT); |
| List<Item> data = loadRangeInternal(position, loadSize); |
| callback.onResult(data, position, COUNT); |
| } |
| |
| @Override |
| public void loadRange(@NonNull LoadRangeParams params, |
| @NonNull LoadRangeCallback<Item> callback) { |
| List<Item> data = loadRangeInternal(params.startPosition, params.loadSize); |
| callback.onResult(data); |
| } |
| } |