Android 中BroadCast Receiver可以用来侦听广播事件。在使用Broadcast 之前,必须使用代码或是在AndroidManifest.xml进行注册。
下面的例子实现使用短信来触发AndroidGraphics2DTutorial中的示例。短信格式为:@demo:xxxx ,xxxx为 示例名称,比如, 启动Colors示例, 则向手机发送: @demo:Colors . 手机在收到短信后,先检测短信格式是否符合 @demo:xxxx, 若符合,这启动对应的示例。
在AndroidGraphics2DTutorial中添加一个自定义的Broadcast Receiver SmsMessageReceiver 用于监测接受到的短信:
public class SmsMessageReceiver extends BroadcastReceiver { private static final String queryString="@demo:"; @Override public void onReceive(Context context, Intent intent) { Bundle extras = intent.getExtras(); if (extras == null) return; Object[] pdus = (Object[]) extras.get("pdus"); for (int i = 0; i < pdus.length; i++) { SmsMessage message = SmsMessage.createFromPdu((byte[]) pdus[i]); String fromAddress = message.getOriginatingAddress(); String fromDisplayName = fromAddress; String msg=message.getMessageBody(); if(msg.startsWith(queryString)){ // Trigger the main activity to fire up a dialog //that shows/reads the received messages Intent di = new Intent(); di.setClass(context, AndroidGraphics2DTutorial.class); di.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK | Intent.FLAG_ACTIVITY_SINGLE_TOP); di.putExtra(AndroidGraphics2DTutorial.SMS_FROM_ADDRESS_EXTRA, fromAddress); di.putExtra(AndroidGraphics2DTutorial.SMS_FROM_DISPLAY_NAME_EXTRA, fromDisplayName); di.putExtra(AndroidGraphics2DTutorial.SMS_MESSAGE_EXTRA, msg); context.startActivity(di); } } } }
onReceive 会在Broadcast 事件发生是执行,这里检测短信内容,如果是以@demo:开头的,则启动AndroidGraphics2DTutorial Main Activity。
修改AndroidMainifest.xml
<receiver android:name=".SmsMessageReceiver" android:enabled="true"> <intent-filter> <action android:name="android.provider.Telephony.SMS_RECEIVED" /> </intent-filter> </receiver>
同时添加permission ,和Java ME类似Android某些API需要指定对应的Permission才可以使用。
<uses-permission android:name="android.permission.SEND_SMS" /> <uses-permission android:name="android.permission.RECEIVE_SMS" />
修改AndroidGraphics2DTutorial.java 来处理SMS消息:
public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); Resources res = getResources(); String[] activity_Names = res.getStringArray(R.array.activity_name); String[] activity_Infos = res.getStringArray(R.array.activity_info); for(int i=0;i<activity_Names.length;i++){ ActivityInfo activityInfo=new ActivityInfo(); activityInfo.activityName=activity_Names[i]; activityInfo.activityInfo=activity_Infos[i]; activityInfo.iconIndex=R.drawable.icon1+i; activityInfos.add(activityInfo); } aa=new ActivityInfoAdapter(this,R.layout.activitylist,activityInfos); setListAdapter(aa); Bundle bundle=getIntent().getExtras(); if(bundle!=null){ mFromAddress = bundle.getString(SMS_FROM_ADDRESS_EXTRA); mMessage = bundle.getString(SMS_MESSAGE_EXTRA); int index=mMessage.indexOf(queryString); if(index>=0){ String demoName=mMessage.substring(index+queryString.length()); Intent intent = new Intent(); intent.setClassName(this, packgeName+".example." +demoName); startActivity(intent); } } }
下面来测试,如果使用设备,则给手机发送@demo:Colors .
如果使用模拟器,则可以启动两个模拟器:
模拟器左上角数字5554,5556为模拟器的号码。发送@demo:Paths ,则自动触发Paths示例,如果AndroidGraphics2DTutorial没有运行,手机收到SMS短信后,会自动启动应用。