Android Studio 0.3.1 button.setOnClickListener（this）;崩潰的應用程序

Question

我有以下代碼正在Eclispe下正常工作，但不斷崩潰在Android Studio下。

public class MainActivity extends Activity implements OnClickListener{ 

private Button playBtn = null; 

@Override 
protected void onCreate(Bundle savedInstanceState) { 
    super.onCreate(savedInstanceState); 
    setContentView(R.layout.activity_main); 

    if (savedInstanceState == null) { 
     getFragmentManager().beginTransaction() 
       .add(R.id.container, new PlaceholderFragment()) 
       .commit(); 
    } 

     playBtn = (Button)findViewById(R.id.play_btn); 
     playBtn.setOnClickListener(this); 
    } 

    .... 

    @Override 
    public void onClick(View view) { 
     if(view.getId()==R.id.play_btn){ 
      //play button 
     } 
    } 

代碼在到達OnCreate（）時崩潰。

任何想法？

感謝

Answer 1

檢查了這一點..

public class MainActivity extends ActionBarActivity implements View.OnClickListener{ 

Button normal; 

@Override 
protected void onCreate(Bundle savedInstanceState) { 
super.onCreate(savedInstanceState); 
setContentView(R.layout.activity_main); 

    normal=(Button)findViewById(R.id.btn_normal); 
    normal.setOnClickListener(this); 
} 

@Override 
public void onClick(View view) { 

switch (view.getId()) 
{ 
    case R.id.btn_normal: 

    //Do what you want on clicking on the button. 

    break; 
} 
} 
} 

它爲我..