changeFragment

MainActivity.java

    /**
     * Change the current displayed fragment by a new one. 
     * - if the fragment is in backstack, it will pop it 
     * - if the fragment is already displayed (trying to change the fragment with the same), it will not do anything
     *
     * @param frag            the new fragment to display
     * @param saveInBackstack if we want the fragment to be in backstack
     * @param animate         if we want a nice animation or not
     */
    private void changeFragment(Fragment frag, boolean saveInBackstack, boolean animate) {
        String backStateName = ((Object) frag).getClass().getName();

        try {
            FragmentManager manager = getSupportFragmentManager();
            boolean fragmentPopped = manager.popBackStackImmediate(backStateName, 0);

            if (!fragmentPopped && manager.findFragmentByTag(backStateName) == null) { 
            	//fragment not in back stack, create it.
                FragmentTransaction transaction = manager.beginTransaction();

                if (animate) {
                    Log.d(TAG, "Change Fragment: animate");
                    transaction.setCustomAnimations(R.anim.slide_in_right, R.anim.slide_out_left, R.anim.slide_in_left, R.anim.slide_out_right);
                }

                transaction.replace(R.id.fragment_container, frag, backStateName);

                if (saveInBackstack) {
                    Log.d(TAG, "Change Fragment: addToBackTack " + backStateName);
                    transaction.addToBackStack(backStateName);
                } else {
                    Log.d(TAG, "Change Fragment: NO addToBackTack");
                }

                transaction.commit();
            } else {
                // custom effect if fragment is already instanciated
            }
        } catch (IllegalStateException exception) {
            Log.w(TAG, "Unable to commit fragment, could be activity as been killed in background. " + exception.toString());
        }
    }

asante sana