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findViewById in onCreate returns NULL when using Fragment


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Call findViewById from onCreateView

public class MainActivity extends ActionBarActivity {

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

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


	/**
	 * A placeholder fragment containing a simple view.
	 */
	public static class PlaceholderFragment extends Fragment {
		public PlaceholderFragment() {
		}

		@Override
		public View onCreateView(LayoutInflater inflater, ViewGroup container,
				Bundle savedInstanceState) {
			View rootView = inflater.inflate(R.layout.fragment_main, container,
					false);
			if (container == null) {
		        return null;
		    }


			 TextView mText;
			mText = (TextView)rootView.findViewById(R.id.idText);
			mText.setText("Hello from fragment_main");

			return rootView;
		}
	}
}




res\layout
activity_main.xml

<FrameLayout xmlns:android="//schemas.android.com/apk/res/android"
    xmlns:tools="//schemas.android.com/tools"
    android:id="@+id/containerMoje"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context="cz.okhelp.autoskola.MainActivity"
    tools:ignore="MergeRootFrame" />



fragment_main.xml

<RelativeLayout xmlns:android="//schemas.android.com/apk/res/android"
    xmlns:tools="//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="cz.okhelp.autoskola.MainActivity$PlaceholderFragment" >

    <TextView
        android:id="@+id/idText"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="@string/hello_world" />

</RelativeLayout>

397LW NO topic_id




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Editace: 2014-07-12 13:48:55
Počet článků v kategorii: 397
Url:findviewbyid-in-oncreate-returns-null-when-using-fragment

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