UISlider - beginTracking behaviour changed on iOS 12

Is this in simulator or device ?

I have an app where I subclass UISlider ; there is a tapGestureRecognizer.

I have set trackPad to react to touch as a click.

=> Check you have the same setting

In simulator, either IOS 11.4 or IOS12, when I just tap on a trackpad, the slider moves

On device, I could only test with IOS11, and tap moves the slider (as for you).

Hi Claude,

The above beginTracking function implementation doesn't require tapGesture to be implemented on subclassed slider to get tap behavior - that was the benefit of using this function. I have tested the above scenario on devices.

Bumping this thread - Anyone knows what changed here?

Any update on how to fix this issue ? Because i am also facing the same issue.

Thank you! This worked for me (Swift version):

override func beginTracking(_ touch: UITouch, with event: UIEvent?) -> Bool {

if #available(iOS 12.0, *) {

let width = self.frame.size.width

let tapPoint = touch.location(in: self)

let fPercent = tapPoint.x/width

let nNewValue = self.maximumValue * Float(fPercent)

if nNewValue != self.value {

self.value = nNewValue

}

}

return true

}

Note that new value calculation is not correct there, this is how it should be, also added `sendAction(_:)` for extra awesomeness.

    override func beginTracking(_ touch: UITouch, with event: UIEvent?) -> Bool {
        let tapPoint = touch.location(in: self)
        let fraction = Float(tapPoint.x / bounds.width)
        let newValue = (maximumValue - minimumValue) * fraction + minimumValue

        if newValue != value {
            value = newValue
            sendActions(for: .valueChanged)
        }

        return true
    }