Fragment cannot be resolved to a type after adding support library in android-Collection of common programming errors

11 years ago

admin

6 minutes

Hi I want to use Fragment and action bar in my project for android 2.2 so I had added Support Library- v4 and v7 in but still I am getting error as

Fragment cannot be resolved to a type and The method getActionBar() is undefined for the type MainActivity.

here is my code:

import java.util.Locale;

import android.R;
import android.app.SearchManager;
import android.content.Intent;
import android.content.res.Configuration;
import android.os.Bundle;
import android.support.v4.app.ActionBarDrawerToggle;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentManager;
import android.support.v4.view.GravityCompat;
import android.support.v4.widget.DrawerLayout;
import android.support.v7.app.ActionBarActivity;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.MenuInflater;
import android.view.MenuItem;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.ImageView;
import android.widget.ListView;
import android.widget.Toast;
import android.support.v7.appcompat.*;
import android.support.v7.app.ActionBar;

public class MainActivity extends ActionBarActivity {
private DrawerLayout mDrawerLayout;
private ListView mDrawerList;
private ActionBarDrawerToggle mDrawerToggle;

private CharSequence mDrawerTitle;
private CharSequence mTitle;
private String[] mPlanetTitles;

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

    mTitle = mDrawerTitle = getTitle();
    mPlanetTitles = getResources().getStringArray(R.array.planets_array);
    mDrawerLayout = (DrawerLayout) findViewById(R.id.drawer_layout);
    mDrawerList = (ListView) findViewById(R.id.left_drawer);

    // set a custom shadow that overlays the main content when the drawer
    // opens
    mDrawerLayout.setDrawerShadow(R.drawable.drawer_shadow,
            GravityCompat.START);
    // set up the drawer's list view with items and click listener
    mDrawerList.setAdapter(new ArrayAdapter(this,
            R.layout.drawer_list_item, mPlanetTitles));
    mDrawerList.setOnItemClickListener(new DrawerItemClickListener());

    // enable ActionBar app icon to behave as action to toggle nav drawer
    getActionBar().setDisplayHomeAsUpEnabled(true);
    getSupportActionbar().setHomeButtonEnabled(true);

    // ActionBarDrawerToggle ties together the the proper interactions
    // between the sliding drawer and the action bar app icon
    mDrawerToggle = new ActionBarDrawerToggle(this, /* host Activity */
    mDrawerLayout, /* DrawerLayout object */
    R.drawable.ic_drawer, /* nav drawer image to replace 'Up' caret */
    R.string.drawer_open, /* "open drawer" description for accessibility */
    R.string.drawer_close /* "close drawer" description for accessibility */
    ) {
        public void onDrawerClosed(View view) {
            getSupportActionbar().setTitle(mTitle);
            invalidateOptionsMenu(); // creates call to
                                        // onPrepareOptionsMenu()
        }

        public void onDrawerOpened(View drawerView) {
            getSupportActionbar().setTitle(mDrawerTitle);
            invalidateOptionsMenu(); // creates call to
                                        // onPrepareOptionsMenu()
        }
    };
    mDrawerLayout.setDrawerListener(mDrawerToggle);

    if (savedInstanceState == null) {
        selectItem(0);
    }
}

@Override
public boolean onCreateOptionsMenu(Menu menu) {
    MenuInflater inflater = getMenuInflater();
    inflater.inflate(R.menu.main, menu);
    return super.onCreateOptionsMenu(menu);
}

/* Called whenever we call invalidateOptionsMenu() */
@Override
public boolean onPrepareOptionsMenu(Menu menu) {
    // If the nav drawer is open, hide action items related to the content
    // view
    boolean drawerOpen = mDrawerLayout.isDrawerOpen(mDrawerList);
    menu.findItem(R.id.action_websearch).setVisible(!drawerOpen);
    return super.onPrepareOptionsMenu(menu);
}

@Override
public boolean onOptionsItemSelected(MenuItem item) {
     // The action bar home/up action should open or close the drawer.
     // ActionBarDrawerToggle will take care of this.
    if (mDrawerToggle.onOptionsItemSelected(item)) {
        return true;
    }
    // Handle action buttons
    switch(item.getItemId()) {
    case R.id.action_websearch:
        // create intent to perform web search for this planet
        Intent intent = new Intent(Intent.ACTION_WEB_SEARCH);
        intent.putExtra(SearchManager.QUERY, getSupportActionbar()().getTitle());
        // catch event that there's no activity to handle intent
        if (intent.resolveActivity(getPackageManager()) != null) {
            startActivity(intent);
        } else {
            Toast.makeText(this, R.string.app_not_available, Toast.LENGTH_LONG).show();
        }
        return true;
    default:
        return super.onOptionsItemSelected(item);
    }
}

/* The click listner for ListView in the navigation drawer */
private class DrawerItemClickListener implements
        ListView.OnItemClickListener {
    @Override
    public void onItemClick(AdapterView parent, View view, int position,
            long id) {
        selectItem(position);
    }
}

private void selectItem(int position) {
    // update the main content by replacing fragments
    Fragment fragment = new PlanetFragment();
    Bundle args = new Bundle();
    args.putInt(PlanetFragment.ARG_PLANET_NUMBER, position);
    fragment.setArguments(args);

    FragmentManager fragmentManager = getFragmentManager();
    fragmentManager.beginTransaction()
            .replace(R.id.content_frame, fragment).commit();

    // update selected item and title, then close the drawer
    mDrawerList.setItemChecked(position, true);
    setTitle(mPlanetTitles[position]);
    mDrawerLayout.closeDrawer(mDrawerList);
}

@Override
public void setTitle(CharSequence title) {
    mTitle = title;
    getSupportActionbar().setTitle(mTitle);
}

/**
 * When using the ActionBarDrawerToggle, you must call it during
 * onPostCreate() and onConfigurationChanged()...
 */

@Override
protected void onPostCreate(Bundle savedInstanceState) {
    super.onPostCreate(savedInstanceState);
    // Sync the toggle state after onRestoreInstanceState has occurred.
    mDrawerToggle.syncState();
}

@Override
public void onConfigurationChanged(Configuration newConfig) {
    super.onConfigurationChanged(newConfig);
    // Pass any configuration change to the drawer toggls
    mDrawerToggle.onConfigurationChanged(newConfig);
}

/**
 * Fragment that appears in the "content_frame", shows a planet
 */
public static class PlanetFragment extends Fragment {
    public static final String ARG_PLANET_NUMBER = "planet_number";

    public PlanetFragment() {
        // Empty constructor required for fragment subclasses
    }

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
            Bundle savedInstanceState) {
        View rootView = inflater.inflate(R.layout.fragment_planet,
                container, false);
        int i = getArguments().getInt(ARG_PLANET_NUMBER);
        String planet = getResources()
                .getStringArray(R.array.planets_array)[i];

        int imageId = getResources().getIdentifier(
                planet.toLowerCase(Locale.getDefault()), "drawable",
                getActivity().getPackageName());
        ((ImageView) rootView.findViewById(R.id.image))
                .setImageResource(imageId);
        getActivity().setTitle(planet);
        return rootView;
    }
}
}

Now here I had tried both

getSupportActionbar() and and getActionBar(). But both gives error.

Also I have activity_main.xml file but in setContentView(R.layout.activity_main); also it gives error as activity_main cannot be resolved or is not a field`

I had already setup compact library file in below screen shot

1. You need to use getSupportActionBar() instead of getActionBar() if you’re using the support library.
2. Make sure your Fragment is from android.support.v4.app.Fragment namespace – this one is from the support library.
Right click on the action bar Sherlock library => Properties => Java Build Path => Order and Export tab => check android support v4 or Android Private Libraries and select OK Right click on your personal project and go to properties => java build path => check Android Private Libraries Clean both projects, it should work.
If supporting API levels lower than 11: import android.support.v7.app.ActionBar

Also your fragment import must be from support library import android.support.v4.app.Fragment

Use getSupportActionBar() instead of getActionBar(). Your activity must extend ActionBarActivity.

In Fragment
```
((ActionBarActivity) getActivity()).getSupportActionBar().setTitle("My Title"); 
```
Check the topic adding the action bar

http://developer.android.com/guide/topics/ui/actionbar.html

Edit:

CHange
```
 getActionBar().setDisplayHomeAsUpEnabled(true);
```
to
```
 getSupportActionBar().setDisplayHomeAsUpEnabled(true);
```
Remove
```
 import android.R;
```