Incompatible types: Fragment cannot be converted to NavigationDrawerFragment

Question

I worked on the application using API 14, but I had to switch to API 10. The application has fragments and activity fragments, I imported libraries and used getFragmentSupportManager because it is v4. However, I have the following error:

I created a dummy application with Drawer layout and fragments with API 10 from the very beginning, it had the same line in the MyActivity file, and that was not an error. Here is my code:

 package az.test2; import android.app.Activity; import android.os.Bundle; import android.view.LayoutInflater; import android.view.Menu; import android.view.MenuItem; import android.view.View; import android.view.ViewGroup; import android.support.v4.widget.DrawerLayout; import android.support.v7.app.ActionBarActivity; import android.support.v7.app.ActionBar; import android.support.v4.app.Fragment; import android.support.v4.app.FragmentManager; import android.view.Gravity; public class MyActivity extends ActionBarActivity implements NavigationDrawerFragment.NavigationDrawerCallbacks { /** * Fragment managing the behaviors, interactions and presentation of the navigation drawer. */ private NavigationDrawerFragment mNavigationDrawerFragment; /** * Used to store the last screen title. For use in {@link #restoreActionBar()}. */ private CharSequence mTitle; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_my); mNavigationDrawerFragment = (NavigationDrawerFragment) getSupportFragmentManager().findFragmentById(R.id.navigation_drawer); mTitle = getTitle(); // Set up the drawer. mNavigationDrawerFragment.setUp( R.id.navigation_drawer, (DrawerLayout) findViewById(R.id.drawer_layout)); } @Override public void onNavigationDrawerItemSelected(int position) { // update the main content by replacing fragments android.support.v4.app.FragmentManager lolo; FragmentManager FM = getSupportFragmentManager(); FragAV fav = new FragAV(); FragW fw = new FragW(); switch (position){ case 0: FM.beginTransaction() .replace(R.id.container, fav).commit(); break; case 1: FM.beginTransaction() .replace(R.id.container, fw).commit(); break; case 2: break; } //FM.beginTransaction().replace(R.id.container, PlaceholderFragment.newInstance(position + 1)).commit(); } public void onSectionAttached(int number) { switch (number) { case 1: mTitle = getString(R.string.title_section1); break; case 2: mTitle = getString(R.string.title_section2); break; case 3: mTitle = getString(R.string.title_section3); break; } } public void restoreActionBar() { ActionBar actionBar = getSupportActionBar(); actionBar.setNavigationMode(ActionBar.NAVIGATION_MODE_STANDARD); actionBar.setDisplayShowTitleEnabled(true); actionBar.setTitle(mTitle); } @Override public boolean onCreateOptionsMenu(Menu menu) { if (!mNavigationDrawerFragment.isDrawerOpen()) { // Only show items in the action bar relevant to this screen // if the drawer is not showing. Otherwise, let the drawer // decide what to show in the action bar. getMenuInflater().inflate(R.menu.my, menu); restoreActionBar(); return true; } return super.onCreateOptionsMenu(menu); } @Override public boolean onOptionsItemSelected(MenuItem item) { // Handle action bar item clicks here. The action bar will // automatically handle clicks on the Home/Up button, so long // as you specify a parent activity in AndroidManifest.xml. int id = item.getItemId(); if (id == R.id.action_settings) { return true; } return super.onOptionsItemSelected(item); } /** * A placeholder fragment containing a simple view. */ public static class PlaceholderFragment extends Fragment { /** * The fragment argument representing the section number for this * fragment. */ private static final String ARG_SECTION_NUMBER = "section_number"; /** * Returns a new instance of this fragment for the given section * number. */ public static PlaceholderFragment newInstance(int sectionNumber) { PlaceholderFragment fragment = new PlaceholderFragment(); Bundle args = new Bundle(); args.putInt(ARG_SECTION_NUMBER, sectionNumber); fragment.setArguments(args); return fragment; } public PlaceholderFragment() { } @Override public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) { View rootView = inflater.inflate(R.layout.fragment_my, container, false); return rootView; } @Override public void onAttach(Activity activity) { super.onAttach(activity); ((MyActivity) activity).onSectionAttached( getArguments().getInt(ARG_SECTION_NUMBER)); } } } 

I did everything I could, but this error seems very rare. Any help would be greatly appreciated.

Answer 1

When using the support package, your slices should extend android.support.v4.app.Fragment , not a regular fragment class.

Answer 2

make sure your drawer snippet class is extended by android.support.v4.app.Fragment not snippet.

Answer 3

change this value

 NavigationDrawerFragment mNavigationDrawerFragment; mNavigationDrawerFragment = (NavigationDrawerFragment) getSupportFragmentManager().findFragmentById(R.id.navigation_drawer); 

to

 Fragment mNavigationDrawerFragment; mNavigationDrawerFragment = (NavigationDrawerFragment) getSupportFragmentManager().findFragmentById(R.id.navigation_drawer); 

Answer 4

in your importing class mNavigationDrawerFragment "import android.support.v4.app.Fragment;" instead of "import android.app.Fragment;"