externes Bild als Hintergrund

import java.io.IOException;
import java.io.InputStream;
import java.net.MalformedURLException;
import java.net.URL;


import android.app.Activity;
import android.graphics.drawable.Drawable;
import android.os.Bundle;
import android.widget.ImageView;


public class Dashboard extends Activity {


	private ImageView mImageView;


	@Override
	protected void onCreate(Bundle savedInstanceState) {
	
		super.onCreate(savedInstanceState);
		setContentView(R.layout.dashboard);
		mImageView=(ImageView) findViewById(R.id.iv_hintergrund);
	}


	@Override
	protected void onStart() {
		
		super.onStart();
		bildLaden();
	}


	private void bildLaden() {
		String urlString="http://xyonline.de/wp-content/uploads/2010/08/android.gif";
		try {
			mImageView.setImageDrawable(
			Drawable.createFromStream((InputStream)
					new URL(urlString).getContent(), "startseite")		
		);
		} catch (MalformedURLException e) {
		e.printStackTrace();
		} catch (IOException e) {
			e.printStackTrace();
		}
		
	}


}

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
  xmlns:android="http://schemas.android.com/apk/res/android"
  android:layout_width="fill_parent"
  android:layout_height="fill_parent"
  android:background="@color/weiss"
  android:orientation="vertical"
  android:padding="10dip">
  <ImageView
  android:layout_width="fill_parent"
  android:layout_height="wrap_content"
  android:id="@+id/iv_hintergrund"
  android:layout_weight="1"
  />
  <Button
  android:layout_width="fill_parent"
  android:layout_height="wrap_content"
  android:text="test"
  />
  




</LinearLayout>