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 17 package androidx.work.impl.constraints.trackers; 18 19 import android.content.BroadcastReceiver; 20 import android.content.Context; 21 import android.content.Intent; 22 import android.content.IntentFilter; 23 import android.support.annotation.NonNull; 24 import android.support.annotation.RestrictTo; 25 import android.util.Log; 26 27 /** 28 * A {@link ConstraintTracker} with a {@link BroadcastReceiver} for monitoring constraint changes. 29 * 30 * @param <T> the constraint data type observed by this tracker 31 * @hide 32 */ 33 @RestrictTo(RestrictTo.Scope.LIBRARY_GROUP) 34 public abstract class BroadcastReceiverConstraintTracker<T> extends ConstraintTracker<T> { 35 private static final String TAG = "BrdcstRcvrCnstrntTrckr"; 36 37 private final BroadcastReceiver mBroadcastReceiver = new BroadcastReceiver() { 38 @Override 39 public void onReceive(Context context, Intent intent) { 40 if (intent != null) { 41 onBroadcastReceive(context, intent); 42 } 43 } 44 }; 45 46 public BroadcastReceiverConstraintTracker(Context context) { 47 super(context); 48 } 49 50 /** 51 * Called when the {@link BroadcastReceiver} is receiving an {@link Intent} broadcast and should 52 * handle the received {@link Intent}. 53 * 54 * @param context The {@link Context} in which the receiver is running. 55 * @param intent The {@link Intent} being received. 56 */ 57 public abstract void onBroadcastReceive(Context context, @NonNull Intent intent); 58 59 /** 60 * @return The {@link IntentFilter} associated with this tracker. 61 */ 62 public abstract IntentFilter getIntentFilter(); 63 64 @Override 65 public void startTracking() { 66 Log.d(TAG, String.format("%s: registering receiver", getClass().getSimpleName())); 67 mAppContext.registerReceiver(mBroadcastReceiver, getIntentFilter()); 68 } 69 70 @Override 71 public void stopTracking() { 72 Log.d(TAG, String.format("%s: unregistering receiver", getClass().getSimpleName())); 73 mAppContext.unregisterReceiver(mBroadcastReceiver); 74 } 75 } 76
