案例：有兩個Activity，第一個Activity中有一個按鈕，這個按鈕的Text是pca，點選之後跳到定外的Activity，在定外一個Activity中發送廣播，改變第一個Activity中按鈕Text的值，變成chy。下面請看代碼：
1.自定義廣播接收者
private class MBroadcastReceiver extends BroadcastReceiver{
@Override
public void onReceive(Context context, Intent intent) {
userName = "chy";
bt1.setText(userName);
}
}
2.注冊廣播
廣播的Action
public static final String USER_BROD_ACTION = "user.broadcast.action";注冊廣播：
MBroadcastReceiver receiver;
receiver = new MBroadcastReceiver();
IntentFilter filter = new IntentFilter(Constants.USER_BROD_ACTION);
registerReceiver(receiver, filter);
3.記的要在Activity銷毀的時候解除廣播的注冊
@Override
protected void onDestroy() {
// TODO Auto-generated method stub
super.onDestroy();
unregisterReceiver(receiver);
}
4.發送廣播
Intent intent = new Intent(Constants.USER_BROD_ACTION);
sendBroadcast(intent);