Get from Android BroadcastReceiver to a UI
I have a receiver that works well, but I can't seem to show a proper UI, although the toast appears correctly. As far as I can tell, this is caused by Android requiring the class to extend Activity, however, the class already extends BroadcastReceiver, so I can't do this. So, I tried to do an Intent, but this failed too. There are no errors, but the screen doesn't show. Source code is below.
Broadcast (Method in AndyRoidAlarm)
public void setAlarm(){
Intent intent = new Intent(AndyRoidAlarm.this, Reciever.class);
PendingIntent sender = PendingIntent.getBroadcast(AndyRoidAlarm.this,
0, intent, 0);
// We want the alarm to go off 30 seconds from now.
Calendar calendar = Calendar.getInstance();
calendar.setTimeInMillis(System.currentTimeMillis());
calendar.add(Calendar.SECOND, 10);
// Schedule the alarm!
AlarmManager am = (AlarmManager)getSystemService(ALARM_SERVICE);
am.set(AlarmManager.RTC_WAKEUP开发者_JS百科, calendar.getTimeInMillis(), sender);
// Tell the user about what we did.
if (mToast != null) {
mToast.cancel();
}
mToast = Toast.makeText(AndyRoidAlarm.this, "Alarm Scheduled for 30secs", Toast.LENGTH_LONG);
mToast.show();
}
Reciever
public class Reciever extends BroadcastReceiver
{
@Override
public void onReceive(Context context, Intent intent)
{
Toast.makeText(context, "Alarm Received", Toast.LENGTH_LONG).show();
Intent i = new Intent();
i.setClass(context, AlarmRing.class);
}
}
Reciever V2
@Override
public void onReceive(Context context, Intent intent)
{
Toast.makeText(context, "Alarm Received", Toast.LENGTH_LONG).show();
Intent foo = new Intent(context, AlarmRing.class);
//foo.putExtra("id", "id");//example, if you wish to pass custom variables
context.startActivity(foo);
}
AlarmRing
public class AlarmRing extends Activity {
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.alarm);
MediaPlayer mp = MediaPlayer.create(getBaseContext(), R.raw.sweetchild);
mp.start();
}
Manifest
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.comaad.andyroidalarm"
android:versionCode="1"
android:versionName="1.0">
<application android:icon="@drawable/icon" android:label="@string/app_name">
<activity android:name=".AndyRoidAlarm"
android:label="@string/app_name">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<receiver android:name="com.comaad.andyroidalarm.Reciever" android:enabled="true">
<intent-filter>
<action android:name="com.comaad.andyroidalarm.Reciever"></action>
</intent-filter>
</receiver>
<activity android:name=".AlarmRing"></activity>
</application>
</manifest>
}
In a BroadcastReceiver
onReceive()
method, if you need a Context
(e.g., to create an Intent
), use the Context
that is passed to you as a parameter of onReceive()
. You even have this code in your onReceive()
-- you're just not doing anything with the resulting Intent
(e.g., calling startActivity()
).
Intent foo = new Intent(this, AlarmRing.class);
foo.putExtra("id", id);//example, if you wish to pass custom variables
this.startActivity(foo);
Edit
Check out this example to use BroadcastReciever within an Activity. http://almondmendoza.com/2009/01/04/getting-battery-information-on-android/
精彩评论