Manage toolbar's navigation and back button from fragment to fragment in android

Question

All of my fragments are controlled through ActionBarActivity (mainActivity), inside mainActivity a DrawerLayout is implemented and all the child fragments are pushed through drawerLayout's list item click. The problem that I'm facing is after pushing a fragment through drawerLayout I want to change the drawer icon into back icon of ToolBar so that user can navigate to previous fragment and to handle the callback of android.R.id.home either inside the same fragment or inside the mainActivity.

Answer 1

You have add Fragment to back stack and add listener in fragment manager like this

getSupportFragmentManager().addOnBackStackChangedListener(new FragmentManager.OnBackStackChangedListener() {
            @Override
            public void onBackStackChanged() {
                if (getSupportFragmentManager().getBackStackEntryCount() > 0) {
                    getSupportActionBar().setDisplayHomeAsUpEnabled(true); // show back button
                    toolbar.setNavigationOnClickListener(new View.OnClickListener() {
                        @Override
                        public void onClick(View v) {
                            onBackPressed();
                        }
                    });
                } else {
                    //show hamburger
                    getSupportActionBar().setDisplayHomeAsUpEnabled(false);
                    toggle.syncState();
                    toolbar.setNavigationOnClickListener(new View.OnClickListener() {
                        @Override
                        public void onClick(View v) {
                            drawerLayout.openDrawer(GravityCompat.START);
                        }
                    });
                }
            }
        });