1 /* 2 * Copyright (C) 2009 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 android.os; 18 19 import com.android.internal.os.IResultReceiver; 20 21 /** 22 * Generic interface for receiving a callback result from someone. Use this 23 * by creating a subclass and implement {@link #onReceiveResult}, which you can 24 * then pass to others and send through IPC, and receive results they 25 * supply with {@link #send}. 26 */ 27 public class ResultReceiver implements Parcelable { 28 final boolean mLocal; 29 final Handler mHandler; 30 31 IResultReceiver mReceiver; 32 33 class MyRunnable implements Runnable { 34 final int mResultCode; 35 final Bundle mResultData; 36 MyRunnable(int resultCode, Bundle resultData)37 MyRunnable(int resultCode, Bundle resultData) { 38 mResultCode = resultCode; 39 mResultData = resultData; 40 } 41 run()42 public void run() { 43 onReceiveResult(mResultCode, mResultData); 44 } 45 } 46 47 class MyResultReceiver extends IResultReceiver.Stub { send(int resultCode, Bundle resultData)48 public void send(int resultCode, Bundle resultData) { 49 if (mHandler != null) { 50 mHandler.post(new MyRunnable(resultCode, resultData)); 51 } else { 52 onReceiveResult(resultCode, resultData); 53 } 54 } 55 } 56 57 /** 58 * Create a new ResultReceive to receive results. Your 59 * {@link #onReceiveResult} method will be called from the thread running 60 * <var>handler</var> if given, or from an arbitrary thread if null. 61 */ ResultReceiver(Handler handler)62 public ResultReceiver(Handler handler) { 63 mLocal = true; 64 mHandler = handler; 65 } 66 67 /** 68 * Deliver a result to this receiver. Will call {@link #onReceiveResult}, 69 * always asynchronously if the receiver has supplied a Handler in which 70 * to dispatch the result. 71 * @param resultCode Arbitrary result code to deliver, as defined by you. 72 * @param resultData Any additional data provided by you. 73 */ send(int resultCode, Bundle resultData)74 public void send(int resultCode, Bundle resultData) { 75 if (mLocal) { 76 if (mHandler != null) { 77 mHandler.post(new MyRunnable(resultCode, resultData)); 78 } else { 79 onReceiveResult(resultCode, resultData); 80 } 81 return; 82 } 83 84 if (mReceiver != null) { 85 try { 86 mReceiver.send(resultCode, resultData); 87 } catch (RemoteException e) { 88 } 89 } 90 } 91 92 /** 93 * Override to receive results delivered to this object. 94 * 95 * @param resultCode Arbitrary result code delivered by the sender, as 96 * defined by the sender. 97 * @param resultData Any additional data provided by the sender. 98 */ onReceiveResult(int resultCode, Bundle resultData)99 protected void onReceiveResult(int resultCode, Bundle resultData) { 100 } 101 describeContents()102 public int describeContents() { 103 return 0; 104 } 105 writeToParcel(Parcel out, int flags)106 public void writeToParcel(Parcel out, int flags) { 107 synchronized (this) { 108 if (mReceiver == null) { 109 mReceiver = new MyResultReceiver(); 110 } 111 out.writeStrongBinder(mReceiver.asBinder()); 112 } 113 } 114 ResultReceiver(Parcel in)115 ResultReceiver(Parcel in) { 116 mLocal = false; 117 mHandler = null; 118 mReceiver = IResultReceiver.Stub.asInterface(in.readStrongBinder()); 119 } 120 121 public static final Parcelable.Creator<ResultReceiver> CREATOR 122 = new Parcelable.Creator<ResultReceiver>() { 123 public ResultReceiver createFromParcel(Parcel in) { 124 return new ResultReceiver(in); 125 } 126 public ResultReceiver[] newArray(int size) { 127 return new ResultReceiver[size]; 128 } 129 }; 130 } 131