Navigation drawer, handling the back button to go to previous fragments?

Just wanted to report my findings even though this question is a little old for anyone else who may have had the same problem with the accepted answer. For me, doing the method suggested in the accepted answer, made the layers overlap, quickly making them unreadable. The code below (adapted from the accepted answer) avoids the overlaying but still adds the screen to the back stack.

fragmentManager.beginTransaction().replace(R.id.container, fragment).addToBackStack("fragBack").commit();

Instead of:

fm.beginTransaction().replace(R.id.main, newFragment).addToBackStack("fragBack").commit();

Call:

fm.beginTransaction().add(R.id.main, newFragment).addToBackStack("fragBack").commit();

addToBackStack works with add.

replace function removes previous fragment and places new fragment so on your back-stack there is only one fragment all the time. So use add function to keep previous fragments on stack.

To always goto fragemnt1 from any fragment onBackPress try to do following:

getFragmentManager().popBackStack();
fm.beginTransaction().add(R.id.main, newFragment).addToBackStack("fragBack").commit();

this will remove last transaction from backstack and add new one. Try this.

In some cases you have to use replace then you cant work with addtobackstack() so you can use this code in MainActivity. In this code when you press back key you always go to first fragment (i call it HomeFragment) and when you are in HomeFragment it ask twice time to go out from application.

 private Boolean exit = false;
@Override
    public void onBackPressed() {
        if (exit) {
            super.onBackPressed();
            return;
        }

    try {
        FragmentManager fragmentManager = getSupportFragmentManager();
        Fragment fragment = fragmentManager.findFragmentByTag("HOME");
        if (fragment != null) {
            if (fragment.isVisible()) {
                this.exit = true;
                Toast.makeText(this, "Press Back again to Exit", Toast.LENGTH_SHORT).show();
            }
        }
        else {
            fragment = HomeFragment.class.newInstance();
            getFragmentManager().popBackStack();
            fragmentManager.beginTransaction().replace(R.id.flContent, fragment, "HOME").commit();
        }
    } catch (Exception e) {

    }
    new Handler().postDelayed(new Runnable() {
        @Override
        public void run() {
            exit = false;
        }
    }, 2000);
}