1/*
2 * Copyright (C) 2011 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 com.example.android.supportv4.content;
18
19import com.example.android.supportv4.R;
20
21import android.app.Activity;
22import android.app.Service;
23import android.content.BroadcastReceiver;
24import android.content.Context;
25import android.content.Intent;
26import android.content.IntentFilter;
27import android.os.Bundle;
28import android.os.Handler;
29import android.os.IBinder;
30import android.os.Message;
31import android.support.v4.app.ServiceCompat;
32import android.support.v4.content.LocalBroadcastManager;
33import android.view.View;
34import android.view.View.OnClickListener;
35import android.widget.Button;
36import android.widget.TextView;
37
38/**
39 * Demonstrates the use of a LocalBroadcastManager to easily communicate
40 * data from a service to any other interested code.
41 */
42public class LocalServiceBroadcaster extends Activity {
43    static final String ACTION_STARTED = "com.example.android.supportv4.STARTED";
44    static final String ACTION_UPDATE = "com.example.android.supportv4.UPDATE";
45    static final String ACTION_STOPPED = "com.example.android.supportv4.STOPPED";
46
47    LocalBroadcastManager mLocalBroadcastManager;
48    BroadcastReceiver mReceiver;
49
50    @Override
51    protected void onCreate(Bundle savedInstanceState) {
52        super.onCreate(savedInstanceState);
53
54        setContentView(R.layout.local_service_broadcaster);
55
56        // This is where we print the data we get back.
57        final TextView callbackData = (TextView)findViewById(R.id.callback);
58
59        // Put in some initial text.
60        callbackData.setText("No broadcast received yet");
61
62        // We use this to send broadcasts within our local process.
63        mLocalBroadcastManager = LocalBroadcastManager.getInstance(this);
64
65        // We are going to watch for interesting local broadcasts.
66        IntentFilter filter = new IntentFilter();
67        filter.addAction(ACTION_STARTED);
68        filter.addAction(ACTION_UPDATE);
69        filter.addAction(ACTION_STOPPED);
70        mReceiver = new BroadcastReceiver() {
71            @Override
72            public void onReceive(Context context, Intent intent) {
73                if (intent.getAction().equals(ACTION_STARTED)) {
74                    callbackData.setText("STARTED");
75                } else if (intent.getAction().equals(ACTION_UPDATE)) {
76                    callbackData.setText("Got update: " + intent.getIntExtra("value", 0));
77                } else if (intent.getAction().equals(ACTION_STOPPED)) {
78                    callbackData.setText("STOPPED");
79                }
80            }
81        };
82        mLocalBroadcastManager.registerReceiver(mReceiver, filter);
83
84        // Watch for button clicks.
85        Button button = (Button)findViewById(R.id.start);
86        button.setOnClickListener(mStartListener);
87        button = (Button)findViewById(R.id.stop);
88        button.setOnClickListener(mStopListener);
89    }
90
91    @Override
92    protected void onDestroy() {
93        super.onDestroy();
94        mLocalBroadcastManager.unregisterReceiver(mReceiver);
95    }
96
97    private OnClickListener mStartListener = new OnClickListener() {
98        public void onClick(View v) {
99            startService(new Intent(LocalServiceBroadcaster.this, LocalService.class));
100        }
101    };
102
103    private OnClickListener mStopListener = new OnClickListener() {
104        public void onClick(View v) {
105            stopService(new Intent(LocalServiceBroadcaster.this, LocalService.class));
106        }
107    };
108
109    public static class LocalService extends Service {
110        LocalBroadcastManager mLocalBroadcastManager;
111        int mCurUpdate;
112
113        static final int MSG_UPDATE = 1;
114
115        Handler mHandler = new Handler() {
116            @Override
117            public void handleMessage(Message msg) {
118                switch (msg.what) {
119                    case MSG_UPDATE: {
120                        mCurUpdate++;
121                        Intent intent = new Intent(ACTION_UPDATE);
122                        intent.putExtra("value", mCurUpdate);
123                        mLocalBroadcastManager.sendBroadcast(intent);
124                        Message nmsg = mHandler.obtainMessage(MSG_UPDATE);
125                        mHandler.sendMessageDelayed(nmsg, 1000);
126                    } break;
127                    default:
128                        super.handleMessage(msg);
129                }
130            }
131        };
132
133        @Override
134        public void onCreate() {
135            super.onCreate();
136            mLocalBroadcastManager = LocalBroadcastManager.getInstance(this);
137        }
138
139        public int onStartCommand(Intent intent, int flags, int startId) {
140            // Tell any local interested parties about the start.
141            mLocalBroadcastManager.sendBroadcast(new Intent(ACTION_STARTED));
142
143            // Prepare to do update reports.
144            mHandler.removeMessages(MSG_UPDATE);
145            Message msg = mHandler.obtainMessage(MSG_UPDATE);
146            mHandler.sendMessageDelayed(msg, 1000);
147            return ServiceCompat.START_STICKY;
148        }
149
150        @Override
151        public void onDestroy() {
152            super.onDestroy();
153
154            // Tell any local interested parties about the stop.
155            mLocalBroadcastManager.sendBroadcast(new Intent(ACTION_STOPPED));
156
157            // Stop doing updates.
158            mHandler.removeMessages(MSG_UPDATE);
159        }
160
161        @Override
162        public IBinder onBind(Intent intent) {
163            return null;
164        }
165    }
166}
167