Using Radio Buttons within a Dialog in Android app

Question

I have an Android app where I want to offer the user the choice of ordering a table using different fields. I've used a dialog with three radio buttons to offer the choice of each sort type.

Below is the code within the dialog code which declares the radio buttons

        LayoutInflater layoutInflater = (LayoutInflater)
        getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        final View layout = layoutInflater.inflate(R.layout.lectindex_dialog, (ViewGroup) findViewById(R.id.lect_index));

        builder.setView(layout);

        // Now configure the AlertDialog
        builder.setTitle(R.string.exindex_title);                       

        final RadioButton radio_date = (RadioButton) findViewById(R.id.RBdate);
        final RadioButton radio_loctn = (RadioButton) findViewById(R.id.RBloctn);
        final RadioButton radio_stream = (RadioButton) findViewById(R.id.RBstream);        
        radio_date.setOnClickListener(radio_listener);
        radio_loctn.setOnClickListener(radio_listener);
        radio_stream.setOnClickListener(radio_listener);

        builder.setNegativeButton(android.R.string.cancel, new DialogInterface.OnClickListener() {
            public void onClick(DialogInterface dialog, int whichButton) {
                // We forcefully dismiss and remove the Dialog, so it cannot be used again (no cached info)
                LecturesActivity.this.removeDialog(SELINDEX_DIALOG_ID);
            }
        });

The code for radio_listener is declared separately like so

        private OnClickListener radio_listener = new OnClickListener() {
          public void onClick(View v) {
            // Perform action on clicks
            RadioButton rb = (RadioButton) v;
            Toast.makeText(LecturesActivity.this, rb.getText(), Toast.LENGTH_SHORT).show();
          }
        }; 

Everything seems to work ok but the code for radio_listener never gets used, Why?