I have a fragment fragmentA on which I have a gridview. The user clicks on a row the grid, I read the value of the first column and pass it to another fragment MapFragment. When I run in debug mode, I can see that the data from fragmentA is passed to the main activity and the app crashes.
What is wrong with code? Am I missing anything?
FATAL EXCEPTION: main java.lang.NullPointerException at com.text.MainActivity.SendData(MainActivity.java:51) at com.test.fragmentAFragment$1.onItemClick(BurnScheduleFragment.java:50) at android.widget.AdapterView.performItemClick(AdapterView.java:301) at android.widget.AbsListView.performItemClick(AbsListView.java:1539) at android.widget.AbsListView$PerformClick.run(AbsListView.java:3332) at android.widget.AbsListView$1.run(AbsListView.java:4554) at android.os.Handler.handleCallback(Handler.java:725) at android.os.Handler.dispatchMessage(Handler.java:92) at android.os.Looper.loop(Looper.java:176) at android.app.ActivityThread.main(ActivityThread.java:5279) at java.lang.reflect.Method.invokeNative(Native Method) at java.lang.reflect.Method.invoke(Method.java:511) at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1102) at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:869) at dalvik.system.NativeStart.main(Native Method)
I have an interface as
`public interface Communicate {
public void SendData(String place);
}
In MapFragment
public class MapFragment extends Fragment {
private MapView map;
HashMap markerMap = new HashMap();
Marker marker;
public MapFragment() {
}
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
Bundle bundle = this.getArguments();
}
public void Show(String title)
{
Marker showMarkerOnMap = (Marker)markerMap.get(title);
showMarkerOnMap.showInfoWindow();
}
private void CreateMarkers(){
GoogleMap gMap = map.getMap();
gMap.setMyLocationEnabled(true);
gMap.setMapType(GoogleMap.MAP_TYPE_NORMAL);
marker = gMap.addMarker(new MarkerOptions().title("One")
.snippet("description")
.position(new LatLng( 0, 0)));
markerMap.put("One", marker);
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.fragment_map, container, false);
if (GooglePlayServicesUtil.isGooglePlayServicesAvailable(getActivity().getApplicationContext()) == ConnectionResult.SUCCESS) {
//Initialze mapview
MapsInitializer.initialize(getActivity());
map = (MapView) view.findViewById(R.id.mapView);
map.onCreate(savedInstanceState);
CreateMarkers();
} else {
Toast.makeText(getActivity(), "Please install google play services", Toast.LENGTH_LONG).show();
}
return view;
}
@Override
public void onResume() {
super.onResume();
map.onResume();
}
@Override
public void onPause() {
super.onPause();
map.onPause();
}
@Override
public void onDestroy() {
super.onDestroy();
map.onDestroy();
}
@Override
public void onLowMemory() {
super.onLowMemory();
map.onLowMemory();
}
}
In My MainAcyivity I have
implemented the SendData as
public void SendData(String place)
{
FragmentManager fragmentManager = getSupportFragmentManager();
MapFragment mapFragment = (MapFragment)fragmentManager.findFragmentById(R.id.mapView);
mapFragment.Show(place);
}
and I have added the method Show in the MapFragment
public void Show(String title)
{
Marker showMarkerOnMap = (Marker)markerMap.get(title);
showMarkerOnMap.showInfoWindow();
}
public class MainActivity extends ActionBarActivity
implements NavigationDrawerFragment.NavigationDrawerCallbacks, Communicate {
private NavigationDrawerFragment mNavigationDrawerFragment;
private CharSequence mTitle;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
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));
}
public void SendData(String place)
{
FragmentManager fragmentManager = getSupportFragmentManager();
MapFragment mapFragment = (MapFragment)fragmentManager.findFragmentById(R.id.mapView);
mapFragment.Show(place);
}
@Override
public void onNavigationDrawerItemSelected(int position)
{
// update the main content by replacing fragments
Fragment fragment = null;
switch (position){
case 0:
fragment= new MapFragment();
break;
case 1:
fragment = new BFragment();
break;
case 2:
break;
default:
fragment = new AFragment();
break;
}
FragmentManager fragmentManager = getSupportFragmentManager();
fragmentManager.beginTransaction()
.replace(R.id.container, fragment)
.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.main, 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();
//noinspection SimplifiableIfStatement
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;
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.fragment_main, container, false);
return rootView;
}
@Override
public void onAttach(Activity activity) {
super.onAttach(activity);
((MainActivity) activity).onSectionAttached(
getArguments().getInt(ARG_SECTION_NUMBER));
}
}
}
`
Map_fragment.xml
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent" >
<com.google.android.gms.maps.MapView
android:id="@+id/mapView"
android:layout_width="fill_parent"
android:layout_height="wrap_content"/>
</RelativeLayout>
