Accessing same PendingIntent in two different blocks

Question

I have 2 buttons save and set alarm and cancel alarm which are meant to do exactly what they suggest.

I have the following 3 lines of code right inside onCreate().

final Intent alarmintent = new Intent(AlarmActivity.this, AlarmReceiver.class);
final AlarmManager alarmManager = (AlarmManager)getSystemService(Context.ALARM_SERVICE);
final PendingIntent sender1 = PendingIntent.getBroadcast(getApplicationContext(), 2, alarmintent, PendingIntent.FLAG_UPDATE_CURRENT |  Intent.FILL_IN_DATA);

Problem

Declaring like this doesn't show any exception but it won't let me achieve the required result.I want to use same PendingIntent,AlarmManager and Intent in two different blocks of code i.e blocks for save and set alarm and cancel's onClickListener().

Note:I can't put those 3 above onCreate() as it throws componentinfo nullpointerexception.

Question

So i need to access same PendingIntent,AlarmManager and Intent in 2 different blocks.How to achieve this?

P.S

1.I tried to make them static but that doesn't work.

2.If i don't use same PendingIntent the desired result(i.e setting up and cancelling alarm) can't be achieved.

Answer 1

Given your code sample, you can simply get back an identical PendingIntent with which you can set the alarm and cancel the alarm. The getBroadcast line that you listed will allow you to do this:

PendingIntent.getBroadcast(getApplicationContext(), 2, alarmintent, PendingIntent.FLAG_UPDATE_CURRENT |  Intent.FILL_IN_DATA);

For a more complete example, see the following IntentSender and AlarmReceiver classes:

public class IntentSender extends Activity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.pending_intent);

        Button setAlarmButton = (Button) findViewById(R.id.set_alarm_button);
        Button cancelAlarmButton = (Button) findViewById(R.id.cancel_alarm_button);

        setAlarmButton.setOnClickListener(new OnClickListener() {
            @Override
            public void onClick(View v) {
                final Intent alarmintent = new Intent(IntentSender.this, AlarmReceiver.class);
                final AlarmManager alarmManager = (AlarmManager) getSystemService(Context.ALARM_SERVICE);
                final PendingIntent sender1 = getPendingIntent(alarmintent);

                alarmManager.set(AlarmManager.RTC, System.currentTimeMillis() + 2000, sender1);
            }
        });

        cancelAlarmButton.setOnClickListener(new OnClickListener() {
            @Override
            public void onClick(View v) {
                final Intent alarmintent = new Intent(IntentSender.this, AlarmReceiver.class);
                final AlarmManager alarmManager = (AlarmManager) getSystemService(Context.ALARM_SERVICE);
                final PendingIntent sender1 = getPendingIntent(alarmintent);

                alarmManager.cancel(sender1);
            }
        });
    }

    private PendingIntent getPendingIntent(final Intent alarmintent) {
        return PendingIntent.getBroadcast(getApplicationContext(), 2, alarmintent, PendingIntent.FLAG_UPDATE_CURRENT |
                                                                                   Intent.FILL_IN_DATA);
    }
}

public class AlarmReceiver extends BroadcastReceiver {

    @Override
    public void onReceive(Context context, Intent intent) {
        Toast.makeText(context, "Received the broadcast!", Toast.LENGTH_SHORT).show();
    }
}

And here's a layout with two buttons that you can click to set and cancel the alarm:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical" >

    <Button
        android:id="@+id/set_alarm_button"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Set Alarm" />

    <Button
        android:id="@+id/cancel_alarm_button"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Cancel Alarm" />

</LinearLayout>

Go ahead and try this out. Click the "Set Alarm" button, wait 2 seconds, and you should see a Toast. For a second test, click "Set Alarm" and then quickly click "Cancel Alarm". You should not see the Toast message.