Re: IKImageView weird Zooming behaviour?

FROM : Randall Meadows
DATE : Thu May 29 18:56:39 2008

On May 29, 2008, at 8:26 AM, Karl von Moller wrote:

> Recently I have been exploring what ImageKit has to offer and by and 
> large it's all very cool. However I have an IKImageView which is 
> hooked up in interface builder to  "+" and "-" button's in the aim 
> to zooming IN and OUT of the image. So this is being handled by IB 
> and not by my own code. However when I build and run the 
> application, the image zooms but always to a view coordinate that's 
> at the bottom left. I tried to override this by creating my own 
> point and setting the zoom factor by using [imageViewOutlet 
> setImageZoomFactor:[sender floatValue] centerPoint:viewsPoint];
>
> But this doesn't solve the problem. Infact, it appears that my point 
> is being ignored all together???
>
> Googling for info on IKImageView is pretty sparse. Can anyone 
> suggest a possible fix?


I went through 2 separate battles with this, trying to get it right. 
I finally came to the conclusion, with the agreement of another 
developer whom I contacted after I found a post of his regarding this 
exact same subject, that much of IK was rushed out the door in an 
effort to support iPhone, and the only testing done (well) was 
whatever Apple engineers needed it to do at the time.

We ended up rolling our own implementations, and it really wasn't that 
hard, nor that much code.

Another huge issue for me was that of live-zooming; there's apparently 
no way to turn off the animation effects, and by using IK with live-
zooming, there is this enormously annoying stuttering effect as the 
current animation is stopped and a new one is started (at least, I 
think that's what it is).

I finally got panning and zooming (from the center point, but 
presumably one could tweak it so it zooms from any point) working 
perfectly (for my needs, anyway!) using a subclass of NSImageView. 
I'll be happy to share this code if you need it, if you contact me off-
list.