What you want to do is definitely possible, however you will need to manually fetch the image and set it on the ImageButton.
Here is a little method you can use to fetch an image:
private Bitmap fetchImage( String urlstr )
{
try
{
URL url;
url = new URL( urlstr );
HttpURLConnection c = ( HttpURLConnection ) url.openConnection();
c.setDoInput( true );
c.connect();
InputStream is = c.getInputStream();
Bitmap img;
img = BitmapFactory.decodeStream( is );
return img;
}
catch ( MalformedURLException e )
{
Log.d( "RemoteImageHandler", "fetchImage passed invalid URL: " + urlstr );
}
catch ( IOException e )
{
Log.d( "RemoteImageHandler", "fetchImage IO exception: " + e );
}
return null;
}
Of course you will want to wrap this method in a thread (Using AsyncTask with SDK 1.5 or UserTask in SDK pre 1.5), then simply call:
myImageButton.setImageBitmap( bitmap );
I think this has answered your question, if not please elaborate further.