1 继承 UITabBarController (这个例子是这样)

2 Setup gestures (L and R)

override func viewDidLoad() {	super.viewDidLoad()	/* setup switch gestures */	self.swipeLeftGesture = UISwipeGestureRecognizer(target: self,		action: "onSwipeGesture:")	self.swipeLeftGesture!.direction		= UISwipeGestureRecognizerDirection.Left	self.view.addGestureRecognizer(self.swipeLeftGesture!)	self.swipeRightGesture = UISwipeGestureRecognizer(target: self,		action: "onSwipeGesture:")	self.swipeRightGesture!.direction		= UISwipeGestureRecognizerDirection.Right	self.view.addGestureRecognizer(self.swipeRightGesture!)}

3 实现gestures callback

/* gestures callback */@IBAction private func onSwipeGesture (sender: UISwipeGestureRecognizer) {	print(__LINE__, __FUNCTION__)	if (nil == self.viewControllers) {		print(__LINE__, "nil viewControllers")		return	}	let dire = sender.direction	var l = false	var r = false	switch (dire) {	case UISwipeGestureRecognizerDirection.Left:		/* right-to-left => left: need to show the right one */		print(__LINE__, "UISwipeGestureRecognizerDirection.Left")		l = true	case UISwipeGestureRecognizerDirection.Right:		print(__LINE__, "UISwipeGestureRecognizerDirection.Right")		r = true	default:		print(__LINE__, "UISwipeGestureRecognizerDirection.xx unhandled")	}	let si = self.selectedIndex	let c = self.viewControllers!.count	print(__LINE__, "si: \(si) c: \(c)")	var fromView: UIView?	var toShow: UIView?	if (l && (si < (c - 1))) {		/* right-to-left => left: need to show the right one */		fromView = self.selectedViewController!.view		toShow = self.viewControllers![si + 1].view	} else if (r && (si > 0)) {		fromView = self.selectedViewController!.view		toShow = self.viewControllers![si - 1].view	}	if (nil != toShow) {		if (l) {			/* right-to-left => left: need to show the right one */			UIView.transitionFromView(fromView!, toView: toShow!, duration: 0.5,				options: UIViewAnimationOptions.TransitionFlipFromRight,				completion: {					if ($0 && (nil != self.viewControllers)) {						let si = self.selectedIndex						let to = si + 1						self.selectedViewController = self.viewControllers![to]					}				})		} else {			UIView.transitionFromView(fromView!, toView: toShow!, duration: 0.5,				options: UIViewAnimationOptions.TransitionFlipFromLeft,				completion: {					if ($0 && (nil != self.viewControllers)) {						let si = self.selectedIndex						let to = si - 1						self.selectedViewController = self.viewControllers![to]					}				})		}	}}var swipeLeftGesture: UISwipeGestureRecognizer?var swipeRightGesture: UISwipeGestureRecognizer?