How to remove a selected item from ListView using CursorAdapter

问题

I am using CursorAdapter and below is my adapter class. My list consists of two text views and one button on each row. Now, on click of the button I want to delete the selected item from the list as well as from the database. How can I get the id of the selected item from the database so that I can delete it and then notify the adapter (refresh the list).

public class MyAdapter extends CursorAdapter {

    Cursor c;
    LayoutInflater inflater;
    Context context;
    private String TAG = getClass().getSimpleName();

    public MyAdapter(Context context, Cursor c) {
        super(context, c);
        this.c = c;
        this.context = context;
        inflater = LayoutInflater.from(context);
    }

    @Override
    public void bindView(View view, Context context, final Cursor cursor) {

        TextView txtName = (TextView) view.findViewById(R.id.txt_name);
        txtName.setText(cursor.getString(cursor.getColumnIndex(Helper.tbl_col_username)));
        TextView txtPassword = (TextView) view.findViewById(R.id.txt_password);
        txtPassword.setText(cursor.getString(cursor.getColumnIndex(Helper.tbl_col_password)));

        Button button = (Button) view.findViewById(R.id.btn_delete);
        button.setOnClickListener(new OnClickListener() {
            public void onClick(View arg0) {
                Log.d(TAG, "Button Click ");
            }
        });
    }
    @Override
    public View newView(Context context, Cursor cursor, ViewGroup parent) {
        View v = inflater.inflate(R.layout.row, null); 
        return v;
    }
}

回答1:

Try some thing like this :

@Override
public void bindView(View view, Context context, final Cursor cursor) {

    TextView txtName = (TextView) view.findViewById(R.id.txt_name);
    txtName.setText(cursor.getString(cursor.getColumnIndex(Helper
                                                           .tbl_col_username)));
    TextView txtPassword = (TextView) view.findViewById(R.id.txt_password);
    txtPassword.setText(cursor.getString(cursor.getColumnIndex(Helper
                                                           .tbl_col_password)));

    final String itemId = cursor.getString(cursor.getColumnIndex("id"));

    Button button = (Button) view.findViewById(R.id.btn_delete);
    button.setOnClickListener(new OnClickListener() {

        public void onClick(View arg0) {
            Log.d(TAG, "Button Click ");
            deleteRecordWithId(itemId);
            cursor.requery();
            notifyDataSetChanged();
        }
    });
}

回答2:

Im assuming this ID is in the cursor. Then simply make your own class DeleteEntryOnClicklistener which implements OnClickListener and let it take the ID in its constructor, and deletes the entry when clicked.

Please comment if I have misunderstood your problem or if Im being unclear, cheers :)

edit:

In your bindView(), change the OnClicklistener to something like this:

long id = cursor.getLong(cursor.getColumnIndex(Helper.tbl_col_id));
button.setOnClicklistener(new DeleteEntryOnClicklistener(id));

And DeleteEntryOnClicklistener should look something like this:

public class DeleteEntryOnClicklistener implements View.OnClickListener {

    long id;

    public DeleteEntryOnClicklistener(long id) {
        this.id = id;
    }

    @Override
    public void onClick(View v) {
        database.deleteEntry(id);
    }

}

来源：https://stackoverflow.com/questions/8416389/how-to-remove-a-selected-item-from-listview-using-cursoradapter