How to make the image zoom in (magnify) by two fingers or using the slider?

How to make the image zoom in (magnify) by two fingers (movement) or using the slider?

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This is what Taifun recommended once: "  you can do it with the webviewer, see an example here http://puravidaapps.com/snippets.php#zoom

You might also be able to do it by simultaneously changing the image height and width from within a slider, where you multiply or divide those values by the slider value.  Be careful here, you will want to make sure that you are only using integer values to multiple and you need to have zoom/unzoom limits (high and low values) set in the slider.     How successful this is is dependent on the image and the actual resolution of the screen and of course, the original size of the image on the screen.    I have not tried this.

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The attached aia demonstrates use of a slider to zoom a simple pgn image.   Zooming this way is feasible.  The example does not have a lot of error control.

I am sure some of you can improve the example a lot.  There is also a Canvas image..I did not experiment with that.  Be aware, your device screen size (in pixels)

is probably a big limitation to this method.

Are there better ways?    I do not know.   If you have one, please post.

ZoomImage.aia

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Thanks for your help!

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