1 /* 2 * Copyright (C) 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.car.settingslib.loader; 18 19 import android.annotation.Nullable; 20 import android.content.Context; 21 import android.support.v4.content.AsyncTaskLoader; 22 23 /** 24 * This class fills in some boilerplate for AsyncTaskLoader to actually load things. 25 * Classes the extend {@link AsyncLoader} need to properly implement required methods expressed in 26 * {@link AsyncTaskLoader} 27 * 28 * <p>Taken from {@link com.android.settingslib.utils.AsyncLoader}. Only change to extend from 29 * support library {@link AsyncTaskLoader} 30 * 31 * @param <T> the data type to be loaded. 32 */ 33 public abstract class AsyncLoader<T> extends AsyncTaskLoader<T> { 34 @Nullable 35 private T mResult; 36 37 public AsyncLoader(Context context) { 38 super(context); 39 } 40 41 @Override 42 protected void onStartLoading() { 43 if (mResult != null) { 44 deliverResult(mResult); 45 } 46 47 if (takeContentChanged() || mResult == null) { 48 forceLoad(); 49 } 50 } 51 52 @Override 53 protected void onStopLoading() { 54 cancelLoad(); 55 } 56 57 @Override 58 public void deliverResult(T data) { 59 if (isReset()) { 60 return; 61 } 62 mResult = data; 63 if (isStarted()) { 64 super.deliverResult(data); 65 } 66 } 67 68 @Override 69 protected void onReset() { 70 super.onReset(); 71 onStopLoading(); 72 mResult = null; 73 } 74 } 75
