xml - gridview and navigation drawer not working together in android

Question

I have downloaded code for gridview and code for navigation bar. Both codes are working fine individually but when I am trying to combine them its giving a runtime error "Unfortunately App Has Stopped".

Below is my code :

MainActivity.java

public class MainActivity extends Activity {
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<String>(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);
    getActionBar().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) {
            getActionBar().setTitle(mTitle);
            invalidateOptionsMenu(); // creates call to onPrepareOptionsMenu()
        }

        public void onDrawerOpened(View drawerView) {
            getActionBar().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, getActionBar().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
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";
    GridView gridview;
    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);
        gridview=(GridView) rootView.findViewById(R.id.gridview);
        ImageAdapter i= new ImageAdapter(this);
        gridview.setAdapter(i);
        return rootView;
    }
}

ImageAdapter.java

public class ImageAdapter extends BaseAdapter {

private static final Context PlanetFragment = null;
private PlanetFragment mContext;
public ImageAdapter(PlanetFragment c) {
mContext = c; 
}

public int getCount() {
return mThumbIds.length;
}

public Object getItem(int position) {
return null;
}

public long getItemId(int position) {
return 0;
}

public View getView(int position, View convertView, ViewGroup parent) {
 ImageView imageView;
    if (convertView == null) {  // if it's not recycled, initialize some attributes
        imageView = new ImageView(PlanetFragment);
        imageView.setLayoutParams(new GridView.LayoutParams(150, 150));
        imageView.setScaleType(ImageView.ScaleType.CENTER_CROP);
        imageView.setPadding(4, 4, 4, 4);
    } else {
        imageView = (ImageView) convertView;
    }

    imageView.setImageResource(mThumbIds[position]);
    return imageView;
}

private Integer[] mThumbIds = {
    R.drawable.snehalaya , R.drawable.prayas_11,
    R.drawable.vs , R.drawable.adr,
    R.drawable.anandvan , R.drawable.bgbb,
    R.drawable.bngvn , R.drawable.dilasa ,
    R.drawable.hohk , R.drawable.jivan,
    R.drawable.mahan,R.drawable.vishva,
    R.drawable.saraswati , R.drawable.samaj,
    R.drawable.atma

};
}

activity_main.xml

<android.support.v4.widget.DrawerLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/drawer_layout"
android:layout_width="match_parent"
android:layout_height="match_parent">

<FrameLayout
    android:id="@+id/content_frame"
    android:layout_width="match_parent"
    android:layout_height="match_parent" />

<ListView
    android:id="@+id/left_drawer"
    android:layout_width="240dp"
    android:layout_height="match_parent"
    android:layout_gravity="start"
    android:choiceMode="singleChoice"
    android:divider="@android:color/transparent"
    android:dividerHeight="0dp"
    android:background="#111"/>
</android.support.v4.widget.DrawerLayout>

drawer_list_item.xml

<TextView xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@android:id/text1"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:textAppearance="?android:attr/textAppearanceListItemSmall"
android:gravity="center_vertical"
android:paddingLeft="16dp"
android:paddingRight="16dp"
android:textColor="#fff"
android:background="?android:attr/activatedBackgroundIndicator"
android:minHeight="?android:attr/listPreferredItemHeightSmall"/>

fragment_planet.xml

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:layout_weight="6"
    android:background="#000000" 
    >
<GridView
    android:id="@+id/gridview"
    android:layout_width="fill_parent"
    android:layout_height="424dp"
    android:layout_marginTop="10dp"
    android:background="#000000"
    android:columnWidth="120dp"
    android:horizontalSpacing="10dp"
    android:numColumns="3"
    android:stretchMode="spacingWidthUniform"
    android:verticalSpacing="10dp" />
</LinearLayout>

Logcat :

01-25 17:27:48.637: E/Trace(892): error opening trace file: No such file or directory (2)
01-25 17:27:49.558: E/AndroidRuntime(892): FATAL EXCEPTION: main
01-25 17:27:49.558: E/AndroidRuntime(892): java.lang.NullPointerException
01-25 17:27:49.558: E/AndroidRuntime(892):  at android.view.ViewConfiguration.get(ViewConfiguration.java:318)
01-25 17:27:49.558: E/AndroidRuntime(892):  at android.view.View.<init>(View.java:3234)
01-25 17:27:49.558: E/AndroidRuntime(892):  at android.widget.ImageView.<init>(ImageView.java:105)
01-25 17:27:49.558: E/AndroidRuntime(892):  at com.example.android.navigationdrawerexample.ImageAdapter.getView(ImageAdapter.java:35)
01-25 17:27:49.558: E/AndroidRuntime(892):  at android.widget.AbsListView.obtainView(AbsListView.java:2159)
01-25 17:27:49.558: E/AndroidRuntime(892):  at android.widget.GridView.onMeasure(GridView.java:1040)
01-25 17:27:49.558: E/AndroidRuntime(892):  at android.view.View.measure(View.java:15513)
01-25 17:27:49.558: E/AndroidRuntime(892):  at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:4827)
01-25 17:27:49.558: E/AndroidRuntime(892):  at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1404)
01-25 17:27:49.558: E/AndroidRuntime(892):  at android.widget.LinearLayout.measureHorizontal(LinearLayout.java:1052)
01-25 17:27:49.558: E/AndroidRuntime(892):  at android.widget.LinearLayout.onMeasure(LinearLayout.java:590)
01-25 17:27:49.558: E/AndroidRuntime(892):  at android.view.View.measure(View.java:15513)
01-25 17:27:49.558: E/AndroidRuntime(892):  at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:4827)
01-25 17:27:49.558: E/AndroidRuntime(892):  at android.widget.FrameLayout.onMeasure(FrameLayout.java:310)
01-25 17:27:49.558: E/AndroidRuntime(892):  at android.view.View.measure(View.java:15513)
01-25 17:27:49.558: E/AndroidRuntime(892):  at android.support.v4.widget.DrawerLayout.onMeasure(DrawerLayout.java:615)
01-25 17:27:49.558: E/AndroidRuntime(892):  at android.view.View.measure(View.java:15513)
01-25 17:27:49.558: E/AndroidRuntime(892):  at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:4827)
01-25 17:27:49.558: E/AndroidRuntime(892):  at andr

Answer 1

Do ImageAdapter initialization like this-

ImageAdapter i= new ImageAdapter(getActivity());

and in ImageAdapter class, make changes like this-

private Activity mContext;
public ImageAdapter(Activity c) 
{
    mContext = c;
}

and then in your getView()-

imageView = new ImageView(mContext);