Can a UIScrollView be adapted to zoom horizontally but not vertically? (how)

Question

I'm trying to make a timeline view that shows events as UIButtons that can be pressed for more info.

Ideally I want to lay out the buttons on a UIScrollView, and allow them to stretch/shrink horizontally, but not vertically.

What I'm trying to accomplish would basically be equivalent to using pinch gestures to resize the content view, and using a scroll view to move side to side - could you point me in the right direction, or suggest how you might accomplish something like this?

My first thought is a UIScrollView to scale a UIView subview, and have the UIView subview contain another subview that does not resize vertically, but only does horizontally when bounds change, and disable vertical scrolling. Maybe I could skip one of these UIView subviews and have only one do everything. It just feels like I'm trying to hack this together like an HTML page or something with all these containers.

Not sure if I've explained any of this well enough to hope for an answer, any help is appreciated though.

Answer 1

Assuming you don't actually want to stretch/shrink the button text, the easiest way is to resize all the buttons. I know, it's a pain.

Answer 2

I've implemented horizontal-only scaling by creating a subclass of UIView that simply overrides setTransform and sets the Y scale to 1 whenever the UIScrollView changes the scale:

@interface DiagramStripView : UIView { }
@end

@implementation DiagramStripView

- (void)setTransform:(CGAffineTransform)newValue;
{
    newValue.d = 1.0;
    [super setTransform:newValue];
}

@end

As the class name suggests, my view holds a series of diagrams that are each one screen wide. When the user lets go, the view controller resets the view's scale to 1 and redraws everything to the new scale:

- (void) scrollViewDidEndZooming:(UIScrollView *)scrollView 
                        withView:(UIView *)view atScale:(float)scale 
{
    diagramStripView.transform = CGAffineTransformIdentity;
    [self redrawDiagrams:scale];
}

Answer 3

Haven't tried this, but you could try placing everything in a UIScrollView, and whenever you detect a zoom level change, adjust all of the child view transforms to CGAffineTransformMakeScale(1.0, 1.0/zoomLevel). This way, the scrollview is zooming everything up, but each subview is scaling themselves vertically downward, canceling out the zoom.