从一个Activity中打开另一个Activity时出错。

Java code

package aa.TActivity;import android.app.Activity;import android.content.Intent;import android.os.Bundle;import android.view.View;import android.view.View.OnClickListener;import android.widget.Button;public class twoActivity extends Activity{    @Override    protected void onCreate(Bundle savedInstanceState) {        // TODO Auto-generated method stub        super.onCreate(savedInstanceState);        Button button2=(Button)findViewById(R.id.button2);        button2.setOnClickListener(new button2OnClickListener());    }}class button2OnClickListener implements OnClickListener{    @Override    public void onClick(View v) {        // TODO Auto-generated method stub        Intent intent2=new Intent();        intent2.setClass(twoActivity.this, TestActivity.class);            }    }

上面倒数第三行中的字“twoActivity.this”报错：No enclosing instance of the type TestActivityActivity is accessible in scope

这个是怎么回事，是怎么造成的呀？

[解决办法]
class button2OnClickListener 放到public class twoActivity 内部，做它的内部类

Java code

class button2OnClickListener implements OnClickListener{    @Override    public void onClick(View v) {        // TODO Auto-generated method stub        Intent intent2=new Intent();        intent2.setClass(twoActivity.this, TestActivity.class);            }}