Question

我想使用滑动手势在我的标签栏之间导航。最简单的方法是什么？我试过这样的事......

import UIKit

class postAdViewController: UIViewController {

    override func viewDidLoad() {
        super.viewDidLoad()
        var leftSwipe = UISwipeGestureRecognizer(target: self, action: Selector("handleSwipes:"))
        view.addGestureRecognizer(leftSwipe)    
    }

    func handleSwipes(sender:UISwipeGestureRecognizer) {
        if (sender.direction == .left) {
            let storyboard = UIStoryboard(name: "Main", bundle: nil)
            let vc = storyboard.instantiateViewController(withIdentifier: "favourireviewcontroller") as! UIViewController
            self.present(vc, animated: true, completion: nil)
        }
        if (sender.direction == .right) {

        }
}

如果我试图向右滑动没有任何反应。滑动时，应用程序崩溃时出现以下错误消息

无法识别的选择器发送到实例0x7f924380a730

Answer 1

如果您要浏览tabBar，那么您应该为swipeGestureRecognizer和.left实施.right，然后使用tabBarController?.selectedIndex，例如这样：

let swipeRight = UISwipeGestureRecognizer(target: self, action: #selector(swiped))
swipeRight.direction = UISwipeGestureRecognizerDirection.right
self.view.addGestureRecognizer(swipeRight)

let swipeLeft = UISwipeGestureRecognizer(target: self, action: #selector(swiped))
swipeLeft.direction = UISwipeGestureRecognizerDirection.left
self.view.addGestureRecognizer(swipeLeft)

func swiped(_ gesture: UISwipeGestureRecognizer) {
    if gesture.direction == .left {
        if (self.tabBarController?.selectedIndex)! < 2 { // set your total tabs here
            self.tabBarController?.selectedIndex += 1
        }
    } else if gesture.direction == .right {
        if (self.tabBarController?.selectedIndex)! > 0 {
            self.tabBarController?.selectedIndex -= 1
        }
    }
}

Answer 2

这是一个通过TabBar控制器左右滑动的Swift4示例。

我不喜欢这个解决方案： - 似乎你应该能够注册一次处理程序并区分处理程序本身的方向，但我无法轻易做到这一点。 - 我也很好奇如何做一个包含拖动视觉效果的手势。我认为我还需要包含一个PanGesture才能实现这一目标。

SELECT item.* FROM 
item INNER JOIN categories ON item.category_id = categories.id
WHERE item.is_active = 1 AND (categories.is_active = 1 AND categories.parent_id IN 
    (SELECT id FROM categories WHERE parent_id IS NULL AND is_active = 1)) OR ( item.is_active = 1 AND categories.parent_id IS NULL AND categories.is_active = 1 )

然后是处理程序：

override func viewDidLoad() {
    super.viewDidLoad()

    let leftSwipe = UISwipeGestureRecognizer(target: self, action: #selector(handleSwipes(_:)))
    let rightSwipe = UISwipeGestureRecognizer(target: self, action: #selector(handleSwipes(_:)))
    leftSwipe.direction = .left
    rightSwipe.direction = .right
    self.view.addGestureRecognizer(leftSwipe)
    self.view.addGestureRecognizer(rightSwipe)

}

Answer 3

尝试使用Swift 4选择器语法：

//below code write in view did appear()
let swipeRight = UISwipeGestureRecognizer(target: self, action:  #selector(swiped))
    swipeRight.direction = UISwipeGestureRecognizerDirection.right
    self.view.addGestureRecognizer(swipeRight)

    let swipeLeft = UISwipeGestureRecognizer(target: self, action: #selector(swiped))
    swipeLeft.direction = UISwipeGestureRecognizerDirection.left
    self.view.addGestureRecognizer(swipeLeft)
  // below code create swipe gestures function

  // MARK: - swiped
   @objc  func swiped(_ gesture: UISwipeGestureRecognizer) {
    if gesture.direction == .left {
        if (self.tabBarController?.selectedIndex)! < 2
        { // set here  your total tabs
            self.tabBarController?.selectedIndex += 1
        }
    } else if gesture.direction == .right {
        if (self.tabBarController?.selectedIndex)! > 0 {
            self.tabBarController?.selectedIndex -= 1
        }
    }
}

Answer 4

尝试使用Swift 3选择器语法：

let leftSwipe = UISwipeGestureRecognizer(target: self, action: #selector(handleSwipes(_:))

喜欢这样

override func viewDidLoad() {
    super.viewDidLoad()

    nextButton.layer.cornerRadius = 7

    let leftSwipe = UISwipeGestureRecognizer(target: self, action: #selector(handleSwipes(_:))
    //leftSwipe.direction = .right
    view.addGestureRecognizer(leftSwipe)
}



func handleSwipes(_ sender: UISwipeGestureRecognizer) {
    if (sender.direction == .left) {
        let storyboard = UIStoryboard(name: "Main", bundle: nil)
        let vc = storyboard.instantiateViewController(withIdentifier: "favourireviewcontroller") as! UIViewController
        self.present(vc, animated: true, completion: nil)
    }

    if (sender.direction == .right) {

    }
}

Swift 3引入了此功能，使编译器能够检查您指定的function是否确实存在。因此，它比以前的概念更安全。

Answer 5

这是先前建议的稍作修改的版本，可用于 Swift 5 和iOS 12。

真正的优势是：

它使用guard语句，因此您不必弄乱在处理程序中解开tabBarController和viewControllers
它不需要硬编码的制表符数量-只需从viewControllers数组中获取它即可。

我也对其进行了一些清理，以使其不再那么冗长。它已经在iOS 12上运行的Swift 5进行了测试（在iOS 11.4上应该没问题，因为这是我测试过的最低部署版本）。

将它们添加到viewDidLoad（或您选择的其他适当位置）：

let swipeRight = UISwipeGestureRecognizer(target: self, action: #selector(handleSwipeGesture))
swipeRight.direction = .right
self.view.addGestureRecognizer(swipeRight)

let swipeLeft = UISwipeGestureRecognizer(target: self, action: #selector(handleSwipeGesture))
swipeLeft.direction = .left
self.view.addGestureRecognizer(swipeLeft)

然后将其添加为事件的处理程序：

@objc func handleSwipeGesture(_ gesture: UISwipeGestureRecognizer) {
  guard let tabBarController = tabBarController, let viewControllers = tabBarController.viewControllers else { return }
  let tabs = viewControllers.count        
  if gesture.direction == .left {
      if (tabBarController.selectedIndex) < tabs {
          tabBarController.selectedIndex += 1
      }
  } else if gesture.direction == .right {
      if (tabBarController.selectedIndex) > 0 {
          tabBarController.selectedIndex -= 1
      }
  }
}

使用滑动手势在标签栏之间导航

5 个答案: