如何添加 UIActionSheet 按钮复选标记？

Question

请问如何最简单的在actionSheet按钮的右边加上复选标记？下面是 Podcasts 应用程序的屏幕截图。

Answer 1

试试这个技巧：

了解如何将 ViewController 显示为弹出窗口
- 将 UITable 添加到 ViewController
- 在 UITable 中显示项目
- 通过添加自定义单元格自定义 UITable
- 在每个自定义单元格中添加一个按钮
- 该按钮将有两种图像，一种是空白框，另一种是带有复选标记的框
- 当用户触摸 table 单元格时，您需要更改与该 table 行对应的按钮图像，以便用户认为他们正在选中或取消选中该框
- 最后在底部添加一个完成按钮以关闭 viewcontroller

Google 所有这些项目都是教程。正如我所说，这不是一项简单的任务，因为 Xcode 中没有开箱即用的复选标记功能。

发件人：

Answer 2

Note that the solution can crash in a future update to iOS. I'm accessing undocumented private APIs. Such solutions are very fragile. Please see the comments below.

最后我通过使用 UIAlertController 得到了答案：

UIAlertController *customActionSheet = [UIAlertController alertControllerWithTitle:nil message:nil preferredStyle:UIAlertControllerStyleActionSheet];

UIAlertAction *firstButton = [UIAlertAction actionWithTitle:@"First Button" style:UIAlertActionStyleDefault handler:^(UIAlertAction * action) {
    //click action
}];
[firstButton setValue:[UIColor blackColor] forKey:@"titleTextColor"];
[firstButton setValue:[UIColor blackColor] forKey:@"imageTintColor"];
[firstButton setValue:@true forKey:@"checked"];

UIAlertAction *secondButton = [UIAlertAction actionWithTitle:@"Second Button" style:UIAlertActionStyleDefault handler:^(UIAlertAction * action) {
    //click action
}];
[secondButton setValue:[UIColor blackColor] forKey:@"titleTextColor"];

UIAlertAction *cancelButton = [UIAlertAction actionWithTitle:@"Cancel" style:UIAlertActionStyleCancel handler:^(UIAlertAction *action){
    //cancel
}];
[cancelButton setValue:[UIColor blackColor] forKey:@"titleTextColor"];

[customActionSheet addAction:firstButton];
[customActionSheet addAction:secondButton];
[customActionSheet addAction:cancelButton];

[self presentViewController:customActionSheet animated:YES completion:nil];

这是结果：

Answer 3

另一种选择是在按钮标题中添加复选标记字符，例如 "Title ✓"。会在标题的旁边，而不是在按钮的右边，不过我觉得问题不大。

Answer 4

Swift版本：4.1

I came across this implementation using creating extension over UIAlertController.

extension UIAlertController {
static func actionSheetWithItems<A : Equatable>(items : [(title : String, value : A)], currentSelection : A? = nil, action : @escaping (A) -> Void) -> UIAlertController {
    let controller = UIAlertController(title: nil, message: nil, preferredStyle: .actionSheet)
    for (var title, value) in items {
        if let selection = currentSelection, value == selection {
            // Note that checkmark and space have a neutral text flow direction so this is correct for RTL
            title = "✔︎ " + title
        }
        controller.addAction(
            UIAlertAction(title: title, style: .default) {_ in
                action(value)
            }
        )
    }
    return controller
}

}

实施：

   func openGenderSelectionPopUp() {
     let selectedValue = "Men" //update this for selected value
     let action = UIAlertController.actionSheetWithItems(items: [("Men","Men"),("Women","Women"),("Both","Both")], currentSelection: selectedValue, action: { (value)  in
        self.lblGender.text = value
     })
     action.addAction(UIAlertAction.init(title: ActionSheet.Button.cancel, style: UIAlertActionStyle.cancel, handler: nil))
     //Present the controller
     self.present(action, animated: true, completion: nil)
}

最终结果：

希望对您有所帮助！

谢谢

Answer 5

Swift 实施：

class Controller: UIViewController {

    var isFirstButtonChecked = true

    @IBAction func buttonTapped(_ sender: UIButton?) {
        let firstButton = UIAlertAction(title: "First Button", style: .default, handler: { [unowned self] _ in
            self.isFirstButtonChecked = true
            print("First Button tapped")
        })
        //Here's the main magic; it's called Key-Value Coding, or KVC:
        firstButton.setValue(isFirstButtonChecked, forKey: "checked")

        let secondButton = UIAlertAction(title: "Second Button", style: .default, handler: { [unowned self] _ in
            self.isFirstButtonChecked = false
            print("Second Button tapped")
        })
        secondButton.setValue(!isFirstButtonChecked, forKey: "checked")

        let cancel = UIAlertAction(title: "Cancel", style: .cancel, handler: nil)

        let alert = UIAlertController(title: nil, message: nil, preferredStyle: .actionSheet)

        alert.addAction(firstButton)
        alert.addAction(secondButton)
        alert.addAction(cancel)
        self.present(alert, animated: true, completion: nil)
    }
}

您还可以使用 enum:

为更多按钮提供复选标记

class Controller: UIViewController {

    enum ButtonChecked {
        case first
        case second
        case third
        case forth
    }

    var buttonChecked: ButtonChecked = .first

    @IBAction func buttonTapped(_ sender: UIButton?) {
        let firstButton = UIAlertAction(title: "First Button", style: .default, handler: { [unowned self] _ in
            self.buttonChecked = .first
            print("First Button tapped")
        })

        let secondButton = UIAlertAction(title: "Second Button", style: .default, handler: { [unowned self] _ in
            self.buttonChecked = .second
            print("Second Button tapped")
        })

        let thirdButton = UIAlertAction(title: "Third Button", style: .default, handler: { [unowned self] _ in
            self.buttonChecked = .third
            print("Third Button tapped")
        })

        let forthButton = UIAlertAction(title: "Forth Button", style: .default, handler: { [unowned self] _ in
            self.buttonChecked = .forth
            print("Forth Button tapped")
        })

        let cancel = UIAlertAction(title: "Cancel", style: .cancel, handler: nil)

        switch buttonChecked {
        case .first:
            firstButton.setValue(true, forKey: "checked")
        case .second:
            secondButton.setValue(true, forKey: "checked")
        case .third:
            thirdButton.setValue(true, forKey: "checked")
        case .forth:
            forthButton.setValue(true, forKey: "checked")
        }

        let alert = UIAlertController(title: nil, message: nil, preferredStyle: .actionSheet)

        alert.addAction(firstButton)
        alert.addAction(secondButton)
        alert.addAction(thirdButton)
        alert.addAction(forthButton)
        alert.addAction(cancel)
        self.present(alert, animated: true, completion: nil)
    }
}

如何添加 UIActionSheet 按钮复选标记？

How to add UIActionSheet button check mark?

ios

objective-c

uiactionsheet

最后我通过使用 UIAlertController 得到了答案：

这是结果：