So I am new to IOS dev and Xcode but far from being a newbie in UI components in many other technologies. I am implementing a UISlider and investigated its API but could not find out how to:
- add snap behavior (0-9, when end user slides to 3.67 thumb will snap to 4)
- a checkbox that will show the value @ runtime(like as a hover tooltip) in the storyboard mode without the need to add a label
- add tics to the slider - 0-9, show a short vertical lines on every round #
Could it be that these basic features are missing? I assumed this will be part of the built-in UISlider.
Thanks
1 + 2) Yes, there is no built-in snap functionality, but you can implement it yourself easily. Just catch the value-changed events of the slider, and update its value to the desired value. The action method for rounding the slider values can update a label displaying the value, too.
2 + 3) You must implement that by yourself. These features are very use case specific. UIKit is rather than a set of small building blocks for general purposes.
The UISlider documentation provided by Apple will help you to figure out what is and is not built in to UIKit's UISlider.
Specifically take a look at the section titled Customizing the Slider’s Appearance, that about sums it up for out-of-the-box customization.
Unfortunately, none of the items you listed are part of UISlider, but subclassing and building out that functionality would not be an issue.
来源：https://stackoverflow.com/questions/40670919/uislider-missing-features-snap-tooltip-and-ticks