Question

I’m trying to send some data from my ListView to another activity through a single option list view fragment.
Here is how flow of data is supposed to be:

ListView (upon choosing an option) -> Single option list view fragment (again, upon choosing an option) -> AnotherActivity.

Code which sends the data from ListView to Fragment:

Bundle b = new Bundle();
b.putString("id", str_projectid);
Projectviewoptions pv = new Projectviewoptions();
pv.setArguments(b);

Projectviewoptions newFragment = new Projectviewoptions();
newFragment.show(getFragmentManager(), "projectoptions");

Code fragment class which receives the data and then sends it to the other activity:

public class Projectviewoptions extends DialogFragment {

String[] option_array = new String[] {"Project details","Edit","Delete","Mark Done"};
Bundle idbundle = getArguments(); 
String myid= idbundle.getString("id"); 

@Override
public Dialog onCreateDialog(Bundle savedInstanceState) {
    AlertDialog.Builder builder = new AlertDialog.Builder(getActivity());
    builder.setTitle("Options")
           .setItems(option_array, new DialogInterface.OnClickListener() {
               public void onClick(DialogInterface dialog, int which) {

                switch(which) {

                case 0: Intent intent = new Intent(getActivity(),ViewProjectDetails.class);
                        intent.putExtra("id", myid);
                        startActivity(intent);
                        break;




                }

           }
    });
    return builder.create();
}
}

Code in the OtherActivity which receives the data passed by the fragment:

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

    String id = getIntent().getExtras().getString("id");
    Toast.makeText(this, id, Toast.LENGTH_LONG).show();
}

The problem:
When I select an option from the ListView, the app crashes. If I remove the code which deals with passing of the data, the app works fine.
That is, if you remove the following code in the ListView:

/*Bundle b = new Bundle();
      b.putString("id", str_projectid);
      Projectviewoptions pv = new Projectviewoptions();
      pv.setArguments(b);*/

and the following, in fragment class:

//Bundle idbundle = getArguments(); 
//String myid= idbundle.getString("id"); 

Here is the LogCat:

12-30 23:21:09.620: W/dalvikvm(7406): threadid=1: thread exiting with uncaught
exception (group=0x409c01f8)
12-30 23:21:09.653: E/AndroidRuntime(7406): FATAL EXCEPTION: main
12-30 23:21:09.653: E/AndroidRuntime(7406): java.lang.NullPointerException
12-30 23:21:09.653: E/AndroidRuntime(7406):     at     
com.kk.project.Projectviewoptions.<init>(Projectviewoptions.java:14)
12-30 23:21:09.653: E/AndroidRuntime(7406):     at 
com.kk.project.ProjectExplorer.onListItemClick(ProjectExplorer.java:53)
12-30 23:21:09.653: E/AndroidRuntime(7406):     at 
android.app.ListActivity$2.onItemClick(ListActivity.java:319)
12-30 23:21:09.653: E/AndroidRuntime(7406):     at 
android.widget.AdapterView.performItemClick(AdapterView.java:292)
12-30 23:21:09.653: E/AndroidRuntime(7406):     at    
android.widget.AbsListView.performItemClick(AbsListView.java:1058)
12-30 23:21:09.653: E/AndroidRuntime(7406):     at  
android.widget.AbsListView$PerformClick.run(AbsListView.java:2514)
12-30 23:21:09.653: E/AndroidRuntime(7406):     at   
android.widget.AbsListView$1.run(AbsListView.java:3168)
12-30 23:21:09.653: E/AndroidRuntime(7406):     at 
android.os.Handler.handleCallback(Handler.java:605)
12-30 23:21:09.653: E/AndroidRuntime(7406):     at   
android.os.Handler.dispatchMessage(Handler.java:92)
12-30 23:21:09.653: E/AndroidRuntime(7406):     at     
android.os.Looper.loop(Looper.java:137)
12-30 23:21:09.653: E/AndroidRuntime(7406):     at  
android.app.ActivityThread.main(ActivityThread.java:4424)
12-30 23:21:09.653: E/AndroidRuntime(7406):     at   
java.lang.reflect.Method.invokeNative(Native Method)
12-30 23:21:09.653: E/AndroidRuntime(7406):     at 
java.lang.reflect.Method.invoke(Method.java:511)
12-30 23:21:09.653: E/AndroidRuntime(7406):     at  
com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:784)
12-30 23:21:09.653: E/AndroidRuntime(7406):     at  
com.android.internal.os.ZygoteInit.main(ZygoteInit.java:551)
12-30 23:21:09.653: E/AndroidRuntime(7406):     at    
dalvik.system.NativeStart.main(Native Method)

Answer 1

You cannot access the Fragment’s arguments outside of any method, simply move this code into onCreateDialog():

Bundle idbundle; 
String myid; 

@Override
public Dialog onCreateDialog(Bundle savedInstanceState) {
    idbundle = getArguments();
    myid = idbundle.getString("id");
    ...

The problem is that getArguments(); returns null when you try to access it before the Fragment’s lifecycle begins, so idbundle.getString() is an NPE.

---

Addition
You are creating two different copies of the same fragment named pv and newFragment, you should show pv and remove newFragment entirely:

Bundle b = new Bundle();
b.putString("id", str_projectid);
Projectviewoptions pv = new Projectviewoptions();
pv.setArguments(b);
pv.show(getFragmentManager(), "projectoptions");

Projectviewoptions newFragment = new Projectviewoptions();
newFragment.show(getFragmentManager(), "projectoptions");