Toast equivalent for Xamarin Forms

Is there any way using Xamarin Forms (not Android or iOS specific) to have a pop-up, like Android does with Toast, that needs no user interaction and goes away after a (short) period of time?

From searching around all I'm seeing are alerts that need user clicks to go away.

Solution 1:

There is a simple solution for this. By using the DependencyService you can easily get the Toast-Like approach in both Android and iOS.

Create an interface in your common package.

public interface IMessage
{
    void LongAlert(string message);
    void ShortAlert(string message);
}

Android section

[assembly: Xamarin.Forms.Dependency(typeof(MessageAndroid))]
namespace Your.Namespace
{
    public class MessageAndroid : IMessage
    {
        public void LongAlert(string message)
        {
            Toast.MakeText(Application.Context, message, ToastLength.Long).Show();
        }
    
        public void ShortAlert(string message)
        {
            Toast.MakeText(Application.Context, message, ToastLength.Short).Show();
        }
    }
}

iOS section

In iOs there is no native solution like Toast, so we need to implement our own approach.

[assembly: Xamarin.Forms.Dependency(typeof(MessageIOS))]
namespace Your.Namespace
{
    public class MessageIOS : IMessage
    {
        const double LONG_DELAY = 3.5;
        const double SHORT_DELAY = 2.0;

        NSTimer alertDelay;
        UIAlertController alert;

        public void LongAlert(string message)
        {
            ShowAlert(message, LONG_DELAY);
        }
        public void ShortAlert(string message)
        {
            ShowAlert(message, SHORT_DELAY);
        }

        void ShowAlert(string message, double seconds)
        {
            alertDelay = NSTimer.CreateScheduledTimer(seconds, (obj) =>
            {
                dismissMessage();
            });
            alert = UIAlertController.Create(null, message, UIAlertControllerStyle.Alert);
            UIApplication.SharedApplication.KeyWindow.RootViewController.PresentViewController(alert, true, null);
        }

        void dismissMessage()
        {
            if (alert != null)
            {
                alert.DismissViewController(true, null);
            }
            if (alertDelay != null)
            {
                alertDelay.Dispose();
            }
        }
    }
}

Please note that in each platform, we have to register our classes with DependencyService.

Now you can access out Toast service in anywhere in our project.

DependencyService.Get<IMessage>().ShortAlert(string message); 
DependencyService.Get<IMessage>().LongAlert(string message);

Solution 2:

Here's a version of Alex Chengalan's iOS code that avoids the UI sticking when multiple messages are shown...

public class MessageIOS : IMessage
    {
        const double LONG_DELAY = 3.5;
        const double SHORT_DELAY = 0.75;

        public void LongAlert(string message)
        {
            ShowAlert(message, LONG_DELAY);
        }

        public void ShortAlert(string message)
        {
            ShowAlert(message, SHORT_DELAY);
        }

        void ShowAlert(string message, double seconds)
        {
            var alert = UIAlertController.Create(null, message, UIAlertControllerStyle.Alert);

            var alertDelay = NSTimer.CreateScheduledTimer(seconds, obj =>
            {
                DismissMessage(alert, obj);
            });

            UIApplication.SharedApplication.KeyWindow.RootViewController.PresentViewController(alert, true, null);
        }

        void DismissMessage(UIAlertController alert, NSTimer alertDelay)
        {
            if (alert != null)
            {
                alert.DismissViewController(true, null);
            }

            if (alertDelay != null)
            {
                alertDelay.Dispose();
            }
        }
    }