eclipse - Android application: "The Application has stopped unexpectedly" - using setText() method -

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• nullpointerexception accessing views in oncreate() 11 answers

i have problem android application. if use settext() method textview have problem like: application has stopped unexpectedly. please try again.

code of application:

public class tc1 extends actionbaractivity {  private textview textview;  @override protected void oncreate(bundle savedinstancestate) {       super.oncreate(savedinstancestate);     setcontentview(r.layout.activity_tc1);      if (savedinstancestate == null) {         getsupportfragmentmanager().begintransaction()                 .add(r.id.container, new placeholderfragment()).commit();     }       textview = (textview)findviewbyid(r.id.textview);     textview.settext("hi"); // wrong line } ... } 

xml fragment:

<relativelayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent" android:layout_height="match_parent" android:paddingbottom="@dimen/activity_vertical_margin" android:paddingleft="@dimen/activity_horizontal_margin" android:paddingright="@dimen/activity_horizontal_margin" android:paddingtop="@dimen/activity_vertical_margin" tools:context="com.example.tc.tc1$placeholderfragment" >  <textview     android:id="@+id/textview"     android:layout_width="wrap_content"     android:layout_height="wrap_content"     android:layout_alignparentleft="true"     android:layout_alignparenttop="true"     android:layout_marginleft="35dp"     android:layout_margintop="20dp"     android:text="text" />  </relativelayout> 

your textview part of fragment xml try activity layout. move findviewbyid() call oncreateview() method of fragment.

for future questions: please not quote "the application has stopped unexpectedly" instead check logcat output error messages , stack traces. error message quoted default crashed information user, nothing provides detailed informations developers.