How to know the calling activity in Android

Question

I have an activity which is called by a few other activities. For example, I have Activity1, Activity2, and Activity3. Activity1 calls Activity2 and passes a parameter. Activity3 also calls Activity2 and passes a parameter.

Now, based on the calling activity, Activity2 performs some task. How do I know which activity is calling Activity2?

Answer 1

A. If you can use startActivityForResult

As per Zain Ali's answer below: If you can start Activity with startActivityForResult() then you can get name of calling Activity class by this.getCallingActivity().getClassName();

B. If you can not use startActivityForResult

If you can not use startActivityForResult(), then you can use following method: You can pass additional parameter in intent, check the value in activity and act accordingly.

1) Define an interface or constants class to define integer constants to indicate calling activity

public interface ActivityConstants {
            public static final int ACTIVITY_1 = 1001;
            public static final int ACTIVITY_2 = 1002;
            public static final int ACTIVITY_3 = 1003;
}

2) Add extra parameter in intent while calling Activity2.

        Intent act2 = new Intent(context, Activity2.class);
                act2.putExtra("calling-activity", ActivityConstants.ACTIVITY_1);
    // or ActivityConstants.ACTIVITY_3 if called form Activity3
startActivity(act2);

3) Check the value of this extra parameter in Activity2 and act accordingly..

int callingActivity = getIntent().getIntExtra("calling-activity", 0);

        switch (callingActivity) {
        case ActivityConstants.ACTIVITY_1:
            // Activity2 is started from Activity1
            break;
        case ActivityConstants.ACTIVITY_3:
            // Activity2 is started from Activity3
            break;
        }