public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity2);
        
        button1=(Button) this.findViewById(R.id.button1);
        button1.setOnClickListener(BtnOnClickListener);
  }    public OnClickListener BtnOnClickListener=new OnClickListener(){
     public void OnClick(View arg0){
Toast toast=Toast.makeText(getApplicationContext(), "test",Toast.LENGTH_LONG);
toast.show();
Intent it=new Intent(Activity2.this,MainActivity.class);
     Activity2.this.startActivity(it);
     finish();
     }
上面的代码,运行后,点button1按钮,没有任何反应,是什么原因?