如何在iphone中创建警报框?
我想创建一个警报类型框,这样当用户试图删除某个内容时,它会说“你确定吗”,然后如果他们确定,就会有一个“是”或“否”。在iphone上实现这一点的最佳方式是什么?UIAlertView似乎是显而易见的确认选择 将代理设置为控制器并实施UIAlertViewDelegate协议使用向用户显示警报消息。使用: 确保您实施:如何在iphone中创建警报框?,iphone,objective-c,ios,uialertview,Iphone,Objective C,Ios,Uialertview,我想创建一个警报类型框,这样当用户试图删除某个内容时,它会说“你确定吗”,然后如果他们确定,就会有一个“是”或“否”。在iphone上实现这一点的最佳方式是什么?UIAlertView似乎是显而易见的确认选择 将代理设置为控制器并实施UIAlertViewDelegate协议使用向用户显示警报消息。使用: 确保您实施: - (void)alertView:(UIAlertView *)alertView clickedButtonAtIndex:(NSInteger)buttonIndex 处
- (void)alertView:(UIAlertView *)alertView clickedButtonAtIndex:(NSInteger)buttonIndex
处理响应。一个
UIAlertView
是最好的方法。在返回到应用程序的正常功能之前,它将在屏幕中间设置动画,使背景变暗,并强制用户对其进行寻址
您可以像这样创建UIAlertView
:
UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"Wait" message:@"Are you sure you want to delete this. This action cannot be undone" delegate:self cancelButtonTitle:@"Delete" otherButtonTitles:@"Cancel", nil];
[alert show];
这将显示消息
然后,要检查他们是点击删除还是取消,请使用以下命令:
- (void)alertView:(UIAlertView *)alertView clickedButtonAtIndex:(NSInteger)buttonIndex{
if (buttonIndex == 0){
//delete it
}
}
确保在头文件(.h
)中,将UIAlertViewDelegate
放在类继承的对象旁边(即UIViewController
或UITableViewController
等),以包括UIAlertViewDelegate
)
有关UIAlertViews
的所有详细信息,请查看
希望这对大家的看法有所帮助。但要确认删除,UIActionSheet可能是更好的选择。请参见使用UIAlertView弹出警报消息
UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"Wait" message:@"Are you sure you want to delete this." **delegate:self** cancelButtonTitle:@"Delete" otherButtonTitles:@"Cancel", nil];
[alert show];
[alert release];
一旦将委托设置为self,就可以对该方法执行操作
- (void)alertView:(UIAlertView *)alertView clickedButtonAtIndex:(NSInteger)buttonIndex
这个帖子很老了,但还是个好问题。有了iOS 8,答案就变了。今天,您更希望将“UIAlertController”与“UIAlertControllerStyle.ActionSheet”的“preferredStyle”一起使用 绑定到按钮的类似于(swift)的代码:
@IBAction func resetClicked(sender: AnyObject) {
let alert = UIAlertController(
title: "Reset GameCenter Achievements",
message: "Highscores and the Leaderboard are not affected.\nCannot be undone",
preferredStyle: UIAlertControllerStyle.ActionSheet)
alert.addAction(
UIAlertAction(
title: "Reset Achievements",
style: UIAlertActionStyle.Destructive,
handler: {
(action: UIAlertAction!) -> Void in
gameCenter.resetAchievements()
}
)
)
alert.addAction(
UIAlertAction(
title: "Show GameCenter",
style: UIAlertActionStyle.Default,
handler: {
(action: UIAlertAction!) -> Void in
self.gameCenterButtonClicked()
}
)
)
alert.addAction(
UIAlertAction(
title: "Cancel",
style: UIAlertActionStyle.Cancel,
handler: nil
)
)
if let popoverController = alert.popoverPresentationController {
popoverController.sourceView = sender as UIView
popoverController.sourceRect = sender.bounds
}
self.presentViewController(alert, animated: true, completion: nil)
}
将产生以下输出:
编辑:代码在iPad、iOS 8+上崩溃。如果按此处所述添加必要的行:对于swift,它非常简单
//Creating the alert controller
//It takes the title and the alert message and prefferred style
let alertController = UIAlertController(title: "Hello Coders", message: "Visit www.simplifiedios.net to learn xcode", preferredStyle: .Alert)
//then we create a default action for the alert...
//It is actually a button and we have given the button text style and handler
//currently handler is nil as we are not specifying any handler
let defaultAction = UIAlertAction(title: "Close Alert", style: .Default, handler: nil)
//now we are adding the default action to our alertcontroller
alertController.addAction(defaultAction)
//and finally presenting our alert using this method
presentViewController(alertController, animated: true, completion: nil)
Ref:由于
UIAlertView
现在已被弃用,我想为未来遇到这种情况的程序员提供一个答案
我将使用UIAlertController
而不是UIAlertView
,如下所示:
@IBAction func showAlert(_ sender: Any) {
let alert = UIAlertController(title: "My Alert", message: "This is my alert", preferredStyle: UIAlertControllerStyle.alert)
alert.addAction(UIAlertAction(title: "Ok", style: UIAlertActionStyle.default, handler: {(action) in
alert.dismiss(animated: true, completion: nil)
}))
self.present(alert,animated:true, completion:nil)
}
在这里,我提供了我在第一个应用程序中使用的警报消息:
@IBAction func showMessage(sender: UIButton) {
let alertController = UIAlertController(title: "Welcome to My First App",
message: "Hello World",
preferredStyle: UIAlertControllerStyle.alert)
alertController.addAction(UIAlertAction(title: "OK",
style: UIAlertActionStyle.default,
handler: nil))
present(alertController, animated: true, completion: nil)
}
为用户响应提供适当的处理程序。@一二三: 你有超过1000名代表;如果您不编辑问题内容,是否有一个“重新标记”链接可用于重新标记问题而无需经过批准?您是否可以添加每个不同样式的示例?我知道用户要求删除,但看到其他类型的UIAlertControllersR(也就是大家都在谈论的好的旧UIAlertView:d)Hi@Zil没问题。我添加了第三种动作样式(默认样式)。我没有其他首选样式的经验,但您可以轻松地获取代码片段并进行尝试。如果您能找到商店中的哪个应用程序,您将收到一份beta tester的邀请;-)这是不推荐的,我们应该使用UIAlertController
@IBAction func showMessage(sender: UIButton) {
let alertController = UIAlertController(title: "Welcome to My First App",
message: "Hello World",
preferredStyle: UIAlertControllerStyle.alert)
alertController.addAction(UIAlertAction(title: "OK",
style: UIAlertActionStyle.default,
handler: nil))
present(alertController, animated: true, completion: nil)
}