Custom UIMenuController using button event 错误 There can only be one UIMenuController instance

Question

我创建了一个按钮，当您按住该按钮时，它会显示用于粘贴文本的标准 ios 菜单按钮，但是当我按住按钮 2 时出现 There can only be one UIMenuController instance. 错误次，我该如何解决？

这是我的代码

override init(frame: CGRect) {
    super.init(frame: frame)
    self.configureView()
}
    
required init?(coder: NSCoder) {
    super.init(coder: coder)
    self.configureView()
}

private func configureView() {
    guard let view = self.loadViewFromNib(nibName: "CustomView") else { return }
    view.frame = self.bounds
    self.addSubview(view)
        
    button.addTarget(self, action: #selector(holdButton), for: .touchDown)
}

@objc func holdButton(_ sender: UIButton) {
    let menuController = UIMenuController()
    menuController.setTargetRect(sender.frame, in: charTextField)
    menuController.setMenuVisible(true, animated: true)
}

此外，当用户单击 paste 按钮时，我如何听取用户的意见？

我想让他点击paste的时候调用这个函数。

func pasteClick() {
    print("pasted", clipboardString())
}

Answer 1

使用 UIMenuController 提供的默认单例实例 (.shared)，而不是创建您自己的实例。

@objc func holdButton(_ sender: UIButton) {
    UIMenuController.shared.setTargetRect(sender.frame, in: charTextField)
    UIMenuController.shared.setMenuVisible(true, animated: true)
}

引用自apple doc：

The singleton UIMenuController instance is referred to as the editing menu.....

Custom UIMenuController using button event 错误 There can only be one UIMenuController instance

Custom UIMenuController using button event error There can only be one UIMenuController instance

ios

swift

uibutton

copy-paste

uimenucontroller