To cancel alarm, we can use the function alarmManager.cancel(pendingIntent).
But...When the MyScheduledActivity is started by MyScheduledReceiver, the main activity AndroidScheduledActivity may be already killed by system or by Task Killer; so we cannot call any function in AndroidScheduledActivity to retrieve the AlarmManager and PendingIntent to cancel the alarm. So we have to re-create both AlarmManager and PendingIntent in MyScheduledActivity.
Modify layout_scheduledactivity.xml to add a Stop button for user to cancel the alarm.
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
>
<TextView
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="--- Scheduled Activity ---"
/>
<Button
android:id="@+id/stop"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text=" Stop! "
/>
<Button
android:id="@+id/dismiss"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:text="Dismiss"
/>
</LinearLayout>
Modify MyScheduledActivity to implement buttonStop.setOnClickListener() and override onClick() to retrieve AlarmManager and PendingIntent, and cancel the alarm using alarmManager.cancel(pendingIntent).
package com.exercise.AndroidScheduledActivity;
import android.app.Activity;
import android.app.AlarmManager;
import android.app.PendingIntent;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
public class MyScheduledActivity extends Activity {
@Override
protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
setContentView(R.layout.layout_scheduledactivity);
Button buttonDismiss = (Button)findViewById(R.id.dismiss);
Button buttonStop = (Button)findViewById(R.id.stop);
buttonDismiss.setOnClickListener(new Button.OnClickListener(){
@Override
public void onClick(View arg0) {
// TODO Auto-generated method stub
finish();
}});
buttonStop.setOnClickListener(new Button.OnClickListener(){
@Override
public void onClick(View arg0) {
// TODO Auto-generated method stub
Intent myIntent = new Intent(getBaseContext(),
MyScheduledReceiver.class);
PendingIntent pendingIntent
= PendingIntent.getBroadcast(getBaseContext(),
0, myIntent, 0);
AlarmManager alarmManager
= (AlarmManager)getSystemService(ALARM_SERVICE);
alarmManager.cancel(pendingIntent);
Intent intent = new Intent();
intent.setClass(MyScheduledActivity.this,
AndroidScheduledActivity.class);
startActivity(intent);
finish();
}});
}
}
Remark: I don't know if it's the formal method to cancel alarm without knowing the original AlarmManager and PendingIntent! But it work as expected in my test.
Download the files.
