Run second activity when first is closed

Question

Can you tell me how to run my second activity if my first activity is closed?There can be some time before the second activity must be opened.Should I use a Service?And please give an example.Thank you so much.

Answer 1

The answer will depend under what condition you want to start the next activity. Following is just a sample, whatever is done in the onDestroy can be copied anywhere else to start the next activity.

Override the onDestroy method of the first activity and then fire an intent to start the second activity. In your first activity,

public class A extends Activity{
    .
    .
    .
    @Override
    public void onDestroy(){
        Intent in = new Intent(this, SecondActivity.class);
        startActivity(in);
    .
    .
    .
    }
}

Make sure both the Activities are metioned in the AndroidManifest.xml

EDIT: To start after some time, you can use a Handler like this. (NOTE : This one is not tested. I hope it works as expected)

public void onDestroy(){
    new Handler.postDelayed(new Runnable(){
                    public void run() {
                        Intent in = new Intent(this, SecondActivity.class);
                        startActivity(in);
                    }                   
                }, 7000);
}

7000 over here is the milliseconds after which you want to start the next activity. i.e the next activity will start after 7s.

All the best :)

Answer 2

if my first activity is closed

For me it sounds like you mean "closed as a result of a user action". Starting a new Activity from onDestroy() is a bad idea since the system may destroy your Activity if it needs to. It can also be destroyed if the device is rotated. A better approach is overriding the back button:

   @Override
   public void onBackPressed() {
     //delay 2nd Activity launch
    super.onBackPressed();
   }

Answer 3

If you try to delay a launch of a second Activity from within your first Activity, you risk it not opening at all, if the app is cleared from memory. Your best bet is to use AlarmManager to schedule the opening of a new Activity after a certain amount of time. This puts the work on the Android OS instead of in your app.

This post contains some code examples of how to approach this.