如何添加UIActionSheet按钮复选标记？

Question

我想知道如何在actionSheet按钮右侧添加复选标记最简单的方法？ Bellow是Podcasts应用程序的屏幕截图。

Answer 1

请注意，解决方案可能会在将来更新到iOS时崩溃。我正在访问未记录的私有API。这种解决方案非常脆弱。请参阅下面的评论。

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];

这就是结果：

Answer 2

Swift版本：4.1

我使用UIAlertController创建扩展来实现这个实现。

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
}

}

执行：

   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)
}

最后结果：

希望有所帮助！

谢谢

Answer 3

另一种选择是在按钮标题上添加一个复选标记字符，如“标题✓”。它将在标题旁边，而不是在按钮的右侧，但我认为这不是一个非常大的问题。

Answer 4

尝试这个技巧：

• 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来自定义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，一个是空白框，另一个是带有复选标记的框 当用户触摸表格单元格时，您需要更改与该表格行对应的按钮图像，以便用户认为他们正在检查或取消选中该框 最后在底部添加一个完成按钮以关闭viewcontroller

谷歌所有这些项目的教程。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。

来自：https://stackoverflow.com/a/40542931/3901620

Answer 5

Swift实现：

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)
    }
}

您还可以使用枚举为更多数量的按钮提供复选标记：

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)
    }
}