Custom dialog with ListView

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/customdialog"
    android:orientation="vertical"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:padding="20dp"
    android:minWidth="300dp">
    <ImageView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:src="@drawable/ic_launcher"/>

    <ListView
        android:id="@+id/dialoglist"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content" />

</LinearLayout>

package com.AndroidCustomDialog;

import android.app.Activity;
import android.app.Dialog;
import android.content.DialogInterface;
import android.content.DialogInterface.OnCancelListener;
import android.content.DialogInterface.OnDismissListener;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.EditText;
import android.widget.ListView;
import android.widget.TextView;
import android.widget.Toast;

public class AndroidCustomDialogActivity extends Activity {

 Button buttonOpenDialog;
 
 String KEY_TEXTPSS = "TEXTPSS";
 static final int CUSTOM_DIALOG_ID = 0;
 
 ListView dialog_ListView;
 
 String[] listContent = {
   "January", "February", "March", "April", 
   "May", "June", "July", "August", "September", 
   "October", "November", "December"};
 
    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        buttonOpenDialog = (Button)findViewById(R.id.opendialog);
        buttonOpenDialog.setOnClickListener(new Button.OnClickListener(){

   @Override
   public void onClick(View arg0) {
    showDialog(CUSTOM_DIALOG_ID);
   }});
  
    }

 @Override
 protected Dialog onCreateDialog(int id) {

  Dialog dialog = null;
  
  switch(id) {
     case CUSTOM_DIALOG_ID:
      dialog = new Dialog(AndroidCustomDialogActivity.this);
      dialog.setContentView(R.layout.dialoglayout);
      dialog.setTitle("Custom Dialog");
      
      dialog.setCancelable(true);
      dialog.setCanceledOnTouchOutside(true);
      
      dialog.setOnCancelListener(new OnCancelListener(){

    @Override
    public void onCancel(DialogInterface dialog) {
     // TODO Auto-generated method stub
     Toast.makeText(AndroidCustomDialogActivity.this, 
       "OnCancelListener", 
       Toast.LENGTH_LONG).show();
    }});
      
      dialog.setOnDismissListener(new OnDismissListener(){

    @Override
    public void onDismiss(DialogInterface dialog) {
     // TODO Auto-generated method stub
     Toast.makeText(AndroidCustomDialogActivity.this, 
       "OnDismissListener", 
       Toast.LENGTH_LONG).show();
    }});

      //Prepare ListView in dialog
      dialog_ListView = (ListView)dialog.findViewById(R.id.dialoglist);
      ArrayAdapter<String> adapter 
       = new ArrayAdapter<String>(this, 
         android.R.layout.simple_list_item_1, listContent);
      dialog_ListView.setAdapter(adapter);
      dialog_ListView.setOnItemClickListener(new OnItemClickListener(){

    @Override
    public void onItemClick(AdapterView<?> parent, View view,
      int position, long id) {
     // TODO Auto-generated method stub
     Toast.makeText(AndroidCustomDialogActivity.this, 
       parent.getItemAtPosition(position).toString() + " clicked", 
       Toast.LENGTH_LONG).show();
     dismissDialog(CUSTOM_DIALOG_ID);
    }});
      
         break;
     }

  return dialog;
 }

 @Override
 protected void onPrepareDialog(int id, Dialog dialog, Bundle bundle) {
  // TODO Auto-generated method stub
  super.onPrepareDialog(id, dialog, bundle);

  switch(id) {
     case CUSTOM_DIALOG_ID:
      //
         break;
     }
  
 }

}

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:orientation="vertical" >

    <TextView
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:text="@string/hello" />

    <Button
        android:id="@+id/opendialog"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:text="Open Dialog" />

</LinearLayout>