2012-09-01 61 views
-1

当我将OnFocusChangeListener设置为editText时,我的应用程序保持崩溃状态..应用程序崩溃并且我logcat发送给我java.lang.nullPointerException ..为什么?Android应用程序崩溃时,将setOnFocusChangeListener设置为EditText

public class MainActivity extends FragmentActivity 
    implements HeadlinesFragment.OnHeadlineSelectedListener { 
private int myYear, myMonth, myDay; 
static final int ID_DATEPICKER = 0; 
/** Called when the activity is first created. */ 
@Override 
public void onCreate(Bundle savedInstanceState) { 
    super.onCreate(savedInstanceState); 

    setContentView(R.layout.news_articles); 
    EditText txt1 = (EditText) findViewById(R.id.editText2); 
    txt1.setOnFocusChangeListener(new View.OnFocusChangeListener() { 
     @Override 
     public void onFocusChange(View v, boolean hasFocus) { 
      final Calendar c = Calendar.getInstance(); 
      myYear = c.get(Calendar.YEAR); 
      myMonth = c.get(Calendar.MONTH); 
      myDay = c.get(Calendar.DAY_OF_MONTH); 
      showDialog(ID_DATEPICKER); 
     } 
     }); 
+3

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回答

1

确保您的布局news_articles.xmleditText2里面。

如果你在网上txt1.setOnFocusChangeListener越来越NullPointerException这可能是造成飞机坠毁后