xamarin.ios - 是/否确认UIAlertView

Question

我通常使用以下代码进行确认警报

int buttonClicked = -1;
UIAlertView alert = new UIAlertView(title, message, null, NSBundle.MainBundle.LocalizedString ("Cancel", "Cancel"),
                                    NSBundle.MainBundle.LocalizedString ("OK", "OK"));
alert.Show ();
alert.Clicked += (sender, buttonArgs) =>  { buttonClicked = buttonArgs.ButtonIndex; };

// Wait for a button press.
while (buttonClicked == -1)
{
    NSRunLoop.Current.RunUntil(NSDate.FromTimeIntervalSinceNow (0.5));
}

if (buttonClicked == 1)
{
    return true;
}
else
{
    return false;
}

这似乎在iOS7中不起作用。循环将继续运行，并且 Clicked事件似乎从未触发过。有没有人提供如何执行确认警报的有效示例？

Answer 1

亚历克斯·科拉多(Alex Corrado)编写了这个美丽的示例，您可以在等待时使用它:

// Displays a UIAlertView and returns the index of the button pressed.
public static Task<int> ShowAlert (string title, string message, params string [] buttons)
{
    var tcs = new TaskCompletionSource<int> ();
    var alert = new UIAlertView {
        Title = title,
        Message = message
    };
    foreach (var button in buttons)
        alert.AddButton (button);
    alert.Clicked += (s, e) => tcs.TrySetResult (e.ButtonIndex);
    alert.Show ();
    return tcs.Task;
}

然后您改为:

int button = await ShowAlert ("Foo", "Bar", "Ok", "Cancel", "Maybe");