问题描述
我想使用计时器快速旋转所有UIPickerView组件，例如彩票轮。我在UIPickerView中有3个组件，希望同时旋转所有组件。我正在下面的代码中旋转UIPickerView中的组件：
let timer = Timer.scheduledTimer(timeInterval: 2.0,target: self,selector: #selector(scrollRandomly),userInfo: nil,repeats: true);
@objc func scrollRandomly() {
let row:Int = Int(arc4random() % 9);
let row1:Int = Int(arc4random() % 9);
let row2:Int = Int(arc4random() % 9);
pickerView.selectRow(row,inComponent: 0,animated: true)
pickerView.selectRow(row1,inComponent: 1,animated: true)
pickerView.selectRow(row2,inComponent: 2,animated: true)
}
谢谢， 鲁沙卜
解决方法
我使用此扩展名
self.view.beginRotating()
DispatchQueue.main.asyncAfter(deadline: .now() + 10) {
self.view.stopRotating()
}
_
fileprivate var RotatingObjectHandle: UInt8 = 0
fileprivate var RotationCycleHandler: UInt8 = 0
extension UIView {
private var shouldStopRotating: Bool {
get {
return objc_getAssociatedObject(self,&RotationCycleHandler) as? Bool ?? false
}
set {
objc_setAssociatedObject(self,&RotationCycleHandler,newValue,.OBJC_ASSOCIATION_RETAIN_NONATOMIC)
}
}
private(set) var isRotating: Bool {
get {
return objc_getAssociatedObject(self,&RotatingObjectHandle) as? Bool ?? false
}
set {
objc_setAssociatedObject(self,&RotatingObjectHandle,.OBJC_ASSOCIATION_RETAIN_NONATOMIC)
}
}
func beginRotating() {
guard !self.isRotating else { return }
self.isRotating = true
self.shouldStopRotating = false
self.rotate()
}
private func rotate() {
UIView.animate(withDuration: 0.65,delay: 0,options: .curveLinear,animations: {
self.transform = self.transform.rotated(by: CGFloat(Double.pi))
},completion: { _ in
if !self.shouldStopRotating {
self.rotate()
} else {
self.isRotating = false
self.shouldStopRotating = false
}
})
}
func stopRotating() {
self.shouldStopRotating = true
}
}