UIAlertController：如何使右键加粗？

Question

当我运行下面的代码时，是按钮总是在左边，我怎样才能把它改到右边并保持它粗体?

func showInAppPurchaseAlert() {
    let alertController = UIAlertController.init(title: "Upgrade?", message: "Do you want to upgrade to pro version?", preferredStyle: .alert)
    alertController.addAction(UIAlertAction.init(title: "No", style: .default, handler: { action in
        self.dismiss(animated: true, completion: nil)
    }))
    let actionUpgrade = UIAlertAction.init(title: "Yes", style: .cancel, handler: { action in
        self.upgradeToPro()
    })
    alertController.addAction(actionUpgrade)
    alertController.preferredAction = actionUpgrade
    self.present(alertController, animated: true, completion: nil)
}

Answer 1

.default 样式总是在右边，.cancel 样式总是在粗体文本。为了改变它，您必须像在代码中那样设置 preferredAction，但问题是您在“是”操作上使用了 .cancel，而这正是您想要的右侧和您对 .default 的“否”操作。我试过你的代码，这个版本符合你的要求。

func showInAppPurchaseAlert() {
    let alertController = UIAlertController.init(title: "Upgrade?", message: "Do you want to upgrade to pro version?", preferredStyle: .alert)
    alertController.addAction(UIAlertAction.init(title: "No", style: .cancel, handler: { action in
        self.dismiss(animated: true, completion: nil)
    }))
    
    let actionUpgrade = UIAlertAction.init(title: "Yes", style: .default, handler: { action in
        self.upgradeToPro()
    })
    alertController.addAction(actionUpgrade)

    alertController.preferredAction = actionUpgrade

    self.present(alertController, animated: true, completion: nil)
}

Answer 2

将 .default 传递给 style:，它将使用取消按钮的外观。

UIAlertController：如何使右键加粗？

UIAlertController: How to make the right button bolded?

ios

swift

uialertcontroller