How to Implement Onbackpressed() in Fragments

onBackPressed() and Fragments

the problem is that Fragment does not have public void onBackPressed() method.

you are getting the error because your method is annotated with @Override but it is not actually overriding any method in the superclass. the purpose of @Override is exactly this one, letting you know that you think you're overriding something but, actually, you aren't

on a side note, what you are trying to do is unnecessary. if you press the back button and you have fragments in the back stack they will be popped automatically. try this

public class FragmentsActivity extends AppCompatActivity {

    public static class FragmentA extends Fragment {
        @Nullable
        @Override
        public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
            View view = new TextView(getActivity());
            view.setLayoutParams(new ViewGroup.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.MATCH_PARENT));
            view.setBackgroundColor(0xffff0000);    
            return view;
        }
    }

    public static class FragmentB extends Fragment {
        @Nullable
        @Override
        public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
            View view = new TextView(getActivity());
            view.setLayoutParams(new ViewGroup.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.MATCH_PARENT));
            view.setBackgroundColor(0xff00ff00);    
            return view;
        }
    }

    @Override
    protected void onCreate(@Nullable Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_fragments);

        FragmentManager fm = getSupportFragmentManager();
        fm.beginTransaction()
                .add(R.id.fragment_container, new FragmentA(), FragmentA.class.getSimpleName())
                .commit();

        // notice addToBackStack here
        fm.beginTransaction()
                .add(R.id.fragment_container, new FragmentB(), FragmentB.class.getSimpleName())
                .addToBackStack(FragmentB.class.getSimpleName())
                .commit();
    }
}

Using onBackPressed() in Android Fragments

Why don't you want to use the back stack? If there is an underlying problem or confusion maybe we can clear it up for you.

If you want to stick with your requirement just override your Activity's onBackPressed() method and call whatever method you're calling when the back arrow in your ActionBar gets clicked.

EDIT: How to solve the "black screen" fragment back stack problem:

You can get around that issue by adding a backstack listener to the fragment manager. That listener checks if the fragment back stack is empty and finishes the Activity accordingly:

You can set that listener in your Activity's onCreate method:

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    FragmentManager fm = getFragmentManager();
    fm.addOnBackStackChangedListener(new OnBackStackChangedListener() {
        @Override
        public void onBackStackChanged() {
            if(getFragmentManager().getBackStackEntryCount() == 0) finish();
        }
    });
}

How to implement onBackPressed() & intents in fragment?

Override onKeyDown instead of onBackPressed. Not necessarily . But this works for me

public boolean onKeyDown(int keyCode, KeyEvent event) {

        switch (keyCode) {
            case KeyEvent.KEYCODE_BACK:
                String cameback="CameBack";
                intent = new Intent(getActivity(),HomeActivity.class);
                intent.putExtra("Comingback", cameback);
                startActivity(intent);
                return true
    }
            return false;
}

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