I'm customizing a UISlider
. I could set a custom thumb image that is higher than the usual thumb however I could not make the track higher when setting a higher minimum track image but the track height remained the same.
It should be possible as in the iPod/Music App on the iPad the volume slider is also higher as the usual slider as you can see here:
(source: cocoia.com)
You need to subclass the slider and override the trackRectForBounds:
method, like this:
- (CGRect)trackRectForBounds:(CGRect)bounds
{
return bounds;
}
The simplest solution for Swift:
class TBSlider: UISlider {
override func trackRectForBounds(bounds: CGRect) -> CGRect {
return CGRectMake(0, 0, bounds.size.width, 4)
}
}
For those that would like to see some working code for changing the track size.
class CustomUISlider : UISlider
{
override func trackRectForBounds(bounds: CGRect) -> CGRect {
//keeps original origin and width, changes height, you get the idea
let customBounds = CGRect(origin: bounds.origin, size: CGSize(width: bounds.size.width, height: 5.0))
super.trackRectForBounds(customBounds)
return customBounds
}
//while we are here, why not change the image here as well? (bonus material)
override func awakeFromNib() {
self.setThumbImage(UIImage(named: "customThumb"), forState: .Normal)
super.awakeFromNib()
}
}
Only thing left is changing the class inside the storyboard:

You can keep using your seekbar action and outlet to the object type UISlider, unless you want to add some more custom stuff to your slider.
use next methods setThumbImage, setMinimumTrackImage, setMaximumTrackImage
[self setThumbImage:[UIImage imageNamed:@"switchThumb.png"] forState:UIControlStateNormal];
[self setMinimumTrackImage:[UIImage imageNamed:@"switchBlueBg.png"] forState:UIControlStateNormal];
[self setMaximumTrackImage:[UIImage imageNamed:@"switchOffPlain.png"] forState:UIControlStateNormal];
and create subclass like this
- (id) initWithFrame: (CGRect)rect{
if ((self=[super initWithFrame:CGRectMake(rect.origin.x,rect.origin.y,90,27)])){
[self awakeFromNib];
}
return self;
}
//use this code
UIImage *volumeLeftTrackImage = [[UIImage imageNamed: @"video_payer_scroll_selection.png"] stretchableImageWithLeftCapWidth: 9 topCapHeight: 0];
UIImage *volumeRightTrackImage= [[UIImage imageNamed: @"video_bar_bg.png"] stretchableImageWithLeftCapWidth: 9 topCapHeight: 0];
[volumeslider setMinimumTrackImage: volumeLeftTrackImage forState: UIControlStateNormal];
[volumeslider setMaximumTrackImage: volumeRightTrackImage forState: UIControlStateNormal];
[volumeslider setThumbImage:[UIImage imageNamed:@"sound_bar_btn.png"] forState:UIControlStateNormal];
[tempview addSubview:volumeslider];
来源:https://stackoverflow.com/questions/8016496/customize-uislider-track-image-height