change layout cause illegalStateException

Question

I show an ImageView in my Fragments to swipe between images. Thanks to this post I could adapt the image and the imageView to the width and height of the original image. But if the image always will be on the left top corner. Then I changed the layout of the fragment, tried to center the imageView horizontally and vertically. But after surrounding it with a RelativeLayout or a LinearLayout, I got a IllegalStateException: The specified child already has a parent. You must call removeView() on the child's parent first.

Not working code in comments:

Fragment:

ImageView image;
Bitmap bitmap = null;

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
        Bundle savedInstanceState)
{
    image = (ImageView) (ImageView) inflater.inflate(R.layout.fragment_image_page, container, false);
    // ViewGroup rootView = (ViewGroup) inflater.inflate(R.layout.fragment_image_page, container, false);
    // image = (ImageView) rootView.findViewById(R.id.imageView);
    new ImageLoad().execute("");
    return image;
}


private class ImageLoad extends AsyncTask<String, Void, Boolean>
{
    int width;
    int height;
    @Override
    protected Boolean doInBackground(String... params)
    {
        URL url;
        try
        {
            url = new URL(
                    "http://www.....jpg");
            // !!! ERROR IN FOLLOWING LINE !!!
            bitmap = BitmapFactory.decodeStream(url.openConnection().getInputStream());
            width = bitmap.getWidth();
            height = bitmap.getHeight();
            int bounding = getResources().getDisplayMetrics().widthPixels;

            if (bounding < width)
            {
                float ratio = width / height;
                width = bounding;
                height = (int) (width / ratio);
                bitmap = Bitmap.createBitmap(bitmap, 0, 0, width, height);
            }
        } catch (MalformedURLException e)
        {
            e.printStackTrace();
        } catch (IOException e)
        {
            e.printStackTrace();
        }
        return null;
    }

    protected void onPostExecute(Boolean doInBackground)
    {
        FrameLayout.LayoutParams param = (FrameLayout.LayoutParams) image.getLayoutParams();
        param.width = width;
        param.height = height;
        image.setLayoutParams(param);
        image.setImageBitmap(bitmap);
    }
}

XML working:

<?xml version="1.0" encoding="utf-8"?>
<ImageView xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/imageView"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:contentDescription="BILD" />

XML not working:

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:layout_centerInParent="true" >

    <ImageView
        android:id="@+id/imageView"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:contentDescription="BILD" />

</RelativeLayout>

score 0 · Answer 1 · answered Jul 04 '13 at 13:13

In onCreateView(), supply null instead of container. You also don't need to cast to ImageView twice.

Like this:

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

score 0 · Accepted Answer · answered Jul 04 '13 at 13:13

After changing xml file , you have to return the root inflated view.Which is your viewgroup.

   @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
            Bundle savedInstanceState)
    {

         ViewGroup rootView = (ViewGroup) inflater.inflate(R.layout.fragment_image_page, container, false);
         image = (ImageView) rootView.findViewById(R.id.imageView);
        new ImageLoad().execute("");
        return rootView;
    }

change layout cause illegalStateException

2 Answers2