how control scroll in webview (Android)

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http://stackoverflow.com – I have an image with low resolution, this image should be shown in a web-view. User can scale the image, Then i need to replace image with higher resolution after the web-view got the zoom-in event. I should load image and scroll to same x and y with higher resolution. Any idea? is it possible to do it smoothly? I have tried this but it is not working wv.scrollTo(x,y); (HowTos)