iOS - Collapsing Animated UISlider - ios

Question

I want to create a collapsing animated UISlider. Basicly, the slider will the size of the thumbimage until it is touched at which point it expands to full size while it is being changed. After the value is changed and the slider is let go, the slider will collapse back to the original size (the size of the thumbimage).
I tried working with touchesBegan and touchesEnd but this didn't get me very far.
So far i've subclassed UISlider and overrode the beginTrackingWithTouch and endTrackingWithTouch. This code kind of accomplishes the collapsing effect (Without the animation of course) but the thumb slider doesn't change anymore. Any ideas on how best to do this?
#import "CollapsingUISlider.h"
#implementation CollapsingUISlider
/*-(void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {
//self.frame = CGRectMake(self.frame.origin.x, self.frame.origin.y, self.frame.size.width * 4.0f, self.frame.size.height);
[super touchesBegan:touches withEvent:event];
}
-(void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event {
// self.frame = CGRectMake(self.frame.origin.x, self.frame.origin.y, self.frame.size.width * 0.25f, self.frame.size.height);
[super touchesEnded:touches withEvent:event];
}*/
-(BOOL)beginTrackingWithTouch:(UITouch *)touch withEvent:(UIEvent *)event {
self.frame = CGRectMake(self.frame.origin.x, self.frame.origin.y, 400, self.frame.size.height);
return YES;
}
-(void)endTrackingWithTouch:(UITouch*)touch withEvent:(UIEvent *)event {
self.frame = CGRectMake(self.frame.origin.x, self.frame.origin.y, 20, self.frame.size.height);
}
-(BOOL) continueTrackingWithTouch:(UITouch *)touch withEvent:(UIEvent *)event {
self.frame = CGRectMake(self.frame.origin.x, self.frame.origin.y, 400, self.frame.size.height);
return self.tracking;
}
#end

Answer 1

I ended up doing something like this:
UIPanGestureRecognizer *panRecognizer = [[UIPanGestureRecognizer alloc] initWithTarget:self action:#selector(move:)];
[panRecognizer setMinimumNumberOfTouches:1];
[panRecognizer setMaximumNumberOfTouches:1];
[platformView addGestureRecognizer:panRecognizer];
-(void)move:(id)sender {
[self.view bringSubviewToFront:[(UIPanGestureRecognizer*)sender view]];
CGPoint translatedPoint = [(UIPanGestureRecognizer*)sender translationInView:self.view];
if ([(UIPanGestureRecognizer*)sender state] == UIGestureRecognizerStateBegan) {
firstX = [[sender view] center].x;
firstY = [[sender view] center].y;
}
translatedPoint = CGPointMake(firstX, firstY+translatedPoint.y);
[[sender view] setCenter:translatedPoint];
if (platformView.center.y < platformCenter.y - offset) {
platformView.center = CGPointMake(platformCenter.x,platformCenter.y-offset);
((UIPanGestureRecognizer*)sender).enabled = NO;
} else if (platformView.center.y > platformCenter.y) {
platformView.center = CGPointMake(platformCenter.x,platformCenter.y);
((UIPanGestureRecognizer*)sender).enabled = NO;
}
}