Android moving back to first activity on button click

Question

I am writing a application where I am dealing with 4 activities, let's say A, B, C & D. Activity A invokes B, B invokes C, C invokes D. On each of the activity, I have a button called "home" button. When user clicks on home button in any of the B, C, D activities, application should go back to A activity screen ?

How to simulate "home" button in this case ?

Answer 1

button.setOnClickListener(new View.OnClickListener() {     public void onClick(View v) {         startActivity(new Intent(D.this, A.class));     } }); 

Declare A in your manifest with the android:launchMode="singleTask". This way, when you call startActivity() from your other activies, and A is already running, it will just bring it to the front. Otherwise it'll launch a new instance.

Answer 2

The only problem i see using android:launchMode="singleTask" is whenever you minimize app and start app by pressing app icon again then app start from scratch and doesn't acquire its state. so i have opted to use

intent.setFlags( Intent.FLAG_ACTIVITY_CLEAR_TOP ); 

which will keep only one instance and clear all activities on top of that.

Intent intent = new Intent( context, MyActivity.class ); intent.setFlags( Intent.FLAG_ACTIVITY_CLEAR_TOP ); current_activity.startActivity( intent );