即使在启动新活动并清除后退堆栈后也要保持根活动

Question

I will be starting activities in the following series:

A->B->C->D Now I want to start another activity suppose E from D and clear the stack but keep activity A as root activity. After starting E the stack should be A->E. How can I achieve this?

Answer 1

You can acheive that with TaskStackBuilder . This dude lets you rebuild stack which you need. You need somethink like this:

final Intent activityAIntent = new Intent(this, ActivityA.class);
activityAIntent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TASK);

TaskStackBuilder.create(this)
                .addNextIntent(activityAIntent)
                .addNextIntent(new Intent(this, ActivityE.class))
                .startActivities();

Answer 2

When your start activity E from D first clear flag top Or finishAffinity(). So all your previous activity is closed. and open first activity from backpress.

Add OnBackPressed method in E Activity.

Like this

   @Override
    public void onBackPressed() {
        super.onBackPressed();
        Intent intent = new Intent(getApplicationContext(), AActivity.class);
        startActivity(intent);
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN) {
            finishAffinity();
        } else {
            finish();
        }
    }