谁可以告诉我这个小代码为什么执行不了吗？
package com.sn.button.activity;

import android.app.Activity;
import android.content.DialogInterface;
import android.content.DialogInterface.OnClickListener;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;

public class MainActivity extends Activity {
private Button button1=null;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
button1=(Button)findViewById(R.id.button1);
button1.setOnClickListener(new OnClickListener());
}

}

class ButtonClick implements OnClickListener
{

@Override
public void onClick(DialogInterface dialog, int which)
{
System.out.println("您点击了按钮。");

}


}

[解决办法]
import android.content.DialogInterface.OnClickListener;
导入不应该是DialogInterface.OnClickListener;