How to check if intent/activity is already open in Android?

Question

So, I'm kind of a noob in Android but I searched a lot for this and I was not able to find a solution:

In my navigation drawer, each row opens a new intent. How can I check if a certain intent is open/active so that I'll use that instead of creating a new one?

I tried using this solution:

Link

But my issue is that the drawer opens the same class everytime, but each class has different "extras." For example:

    public void itemClicked(View view, int position) {
        Intent intent=null;
        switch (position) {
            case 1:
                intent = new Intent(getActivity(), DisplayActivity.class);
                intent.putExtra("ARGUMENT","SECTION 1");
                break;
            case 2:
                intent = new Intent(getActivity(), DisplayActivity.class);
                 intent.putExtra("ARGUMENT","SECTION 2");
               break;
            case 3:
                intent = new Intent(getActivity(), DisplayActivity.class);
                intent.putExtra("ARGUMENT","SECTION 3");
                break;
           }        
      startActivity(intent);
    }

How can I check if an intent with that class and with those extras is already open?

Thanks!

you can use `shared preferences` or extent from Application class where you store last/current activity visible. — Murtaza Khursheed Hussain, Jun 15 '15 at 07:37

score 2 · Answer 1 · answered Jun 15 '15 at 07:41

You can use shared preferences or extent from Application class where you store last/current activity visible

If you extend class for Application or you are targetting devices API Level 14 or above you can implement ActivityLifecycleCallbacks.

Sample Code

public class MyApplication extends Application implements ActivityLifecycleCallbacks {
    private static boolean isMySomeActivityVisible;

    @Override
    public void onCreate() {
        super.onCreate();

        // Register to be notified of activity state changes
        registerActivityLifecycleCallbacks(this);
        ....
    }

    @Override
    public void onActivityResumed(Activity activity) {
        if (activity instanceof YOURACTIVITY) {
             isMySomeActivityVisible = true;
        }
    }

    @Override
    public void onActivityStopped(Activity activity) {
        if (activity instanceof YOURACTIVITY) {
             isMySomeActivityVisible = false;
        }
    }

    // Other state change callback stubs
    ....
}

Thanks for your answer! Im going to test it now. But how about extras that I have in intents? Can I check for these here as well? — tj56, Jun 15 '15 at 08:02
Also, Im not so sure how I can use this. Where does the checking of the "DisplayActivity" class come into play? Thanks! — tj56, Jun 15 '15 at 08:10
You can make this singleton and call the instance when you want to check which activity is in display — Murtaza Khursheed Hussain, Jun 15 '15 at 09:59

score 1 · Answer 2 · answered Jun 15 '15 at 09:28

1

You can also check about the launch modes in android which you make use of. I think it will serve your requirement well. For your reference have a look at this http://www.intridea.com/blog/2011/6/16/android-understanding-activity-launchmode

answered Jun 15 '15 at 09:28

frost

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How to check if intent/activity is already open in Android?

2 Answers2