Question

I have a ListView with a custom adapter that extends CursorAdapter.
that ListView also has a footer view

when a list item is clicked (which is not the footer) in the OnListItemClickListener
I get a ClassCastException on

Cursor c = ((CursorAdapter)l.getAdapter()).getCursor();

E/AndroidRuntime( 8579): FATAL EXCEPTION: main
E/AndroidRuntime( 8579): java.lang.ClassCastException: android.widget.HeaderViewListAdapter
E/AndroidRuntime( 8579):        at com.gbenhaim.dealsapp.BrowsePostsActivity.onListItemClick(BrowsePostsActivity.java:277)
E/AndroidRuntime( 8579):        at android.app.ListActivity$2.onItemClick(ListActivity.java:319)
E/AndroidRuntime( 8579):        at android.widget.AdapterView.performItemClick(AdapterView.java:284)
E/AndroidRuntime( 8579):        at android.widget.ListView.performItemClick(ListView.java:3513)
E/AndroidRuntime( 8579):        at android.widget.AbsListView$PerformClick.run(AbsListView.java:1812)
E/AndroidRuntime( 8579):        at android.os.Handler.handleCallback(Handler.java:587)
E/AndroidRuntime( 8579):        at android.os.Handler.dispatchMessage(Handler.java:92)
E/AndroidRuntime( 8579):        at android.os.Looper.loop(Looper.java:130)
E/AndroidRuntime( 8579):        at android.app.ActivityThread.main(ActivityThread.java:3683)
E/AndroidRuntime( 8579):        at java.lang.reflect.Method.invokeNative(Native Method)
E/AndroidRuntime( 8579):        at java.lang.reflect.Method.invoke(Method.java:507)
E/AndroidRuntime( 8579):        at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:839)
E/AndroidRuntime( 8579):        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:597)
E/AndroidRuntime( 8579):        at dalvik.system.NativeStart.main(Native Method)

the footer view is inflated and added to the listview before setting the adapter.

clicking on the footer works fine and
if I don’t add the footer to the listview clicking on a list item works fine

what is the problem and how do i fix it ?

EDIT:
my custom adapter extends CursorAdapter and overrides BindView and NewView

@Override
protected void onListItemClick(ListView l, View v, int position, long id) {
if (v == footer) {
    ...
} else {
        Cursor c = ((CursorAdapter) l.getAdapter()).getCursor();
        c.moveToPosition(position); 
        ...
    }
}

class PostAdapter extends CursorAdapter {

    public PostAdapter(Context context, Cursor c) {
        super(context, c);
        // TODO Auto-generated constructor stub
    }

    @Override
    public void bindView(View view, Context context, Cursor cursor) {
        // DISPLAY DATA in view
                    ...
    }

    @Override
    public View newView(Context context, Cursor cursor, ViewGroup parent) {
        LayoutInflater inflater = LayoutInflater.from(context);
        return inflater.inflate(R.layout.postrow, parent, false);
    }
}

Answer 1

Well from the looks of the error it doesn’t seem to agree that your HeaderViewListAdapter can be casted to a CursorAdapter.

Why don’t you show us some of the code for your HeaderViewListAdapter?

Edit: It appears that becuase you have headers/footers in your ListView, the adapter you get back is a HeadListViewAdapter, which wraps your original adapter.

From Android Dev API:

HeaderViewListAdapter

ListAdapter used when a ListView has header views. This ListAdapter wraps another one and also keeps track of the header views and their associated data objects. 

http://developer.android.com/reference/android/widget/HeaderViewListAdapter.html

The following is all educated guesses, but try it out:

1. l.getAdapter <– HeaderListViewAdapter

2. ((HeaderListViewAdapter)l.getAdapter).getWrappedAdapter() <– The custom adapter you created.

So instead of this: Cursor c = ((CursorAdapter) l.getAdapter()).getCursor();


Try this:

HeaderViewListAdapter hlva = (HeaderViewListAdapter)l.getAdapter();
PostAdapter postAdapter = (PostAdapter)hlva.getWrappedAdapter();
Cursor cur = postAdapter.getCursor();

I broke it up so that if it doesn’t work, you’ll know exactly which statement is erroring out.