xcode - Swift- 设置可见菜单 Controller

Question

我正在尝试显示一个 UimenuController，但我无法查看它。我该怎么办？

let MenuController: UIMenuController = UIMenuController.sharedMenuController()
 MenuController.menuVisible = true
 MenuController.arrowDirection = UIMenuControllerArrowDirection.Down
 MenuController.setTargetRect(CGRectMake(100, 80, 50, 50), inView: self.view)
 let MenuItem_1: UIMenuItem = UIMenuItem(title: "Menu", action: "delete:")
 let MenuItems: NSArray = [delete]
 MenuController.menuItems = MenuItems

Answer 1

为了实际显示菜单，您需要执行以下操作:

1. 在获得 sharedMenuController 之前调用 becomeFirstResponder()
2. 最后调用 menu.setMenuVisible(true, animated: true)
3. 重写 canBecomeFirstResponder 函数
4. 覆盖 canPerformAction 函数
5. 为选择器编写函数

举个例子

func someFunc() {
    becomeFirstResponder()
    var menu = UIMenuController.sharedMenuController()
    var deleteItem = UIMenuItem(title: "Delete me", action: Selector("deleteLine"))
    menu.menuItems = [deleteItem]
    menu.setTargetRect(CGRectMake(100, 80, 50, 50), inView: self)
    menu.setMenuVisible(true, animated: true)
}

func deleteLine() {
    //Do something here
}

override func canBecomeFirstResponder() -> Bool {
    return true
}

override func canPerformAction(action: Selector, withSender sender: AnyObject?) -> Bool {
    // You need to only return true for the actions you want, otherwise you get the whole range of
    //  iOS actions. You can see this by just removing the if statement here.
    if action == Selector("deleteLine") {
        return true
    }
    return false
}