Xamarin Forms DisplayPrompt apply Keyboard renderer - xamarin.forms

Question

My goal is to add an OK button on iOS numeric keyboard; I can achieve that very easily with a custom renderer :
public class ExtendedEntryRenderer : EntryRenderer
{
protected override void OnElementChanged(ElementChangedEventArgs<Entry> e)
{
base.OnElementChanged(e);
if (Element == null)
{
return;
}
// Check only for Numeric keyboard
if (this.Element.Keyboard == Keyboard.Numeric)
{
this.AddDoneButton();
}
}
/// <summary>
/// <para>Add toolbar with Done button</para>
/// </summary>
protected void AddDoneButton()
{
var toolbar = new UIToolbar(new RectangleF(0.0f, 0.0f, 50.0f, 44.0f));
var doneButton = new UIBarButtonItem(UIBarButtonSystemItem.Done, delegate
{
this.Control.ResignFirstResponder();
var baseEntry = this.Element.GetType();
((IEntryController)Element).SendCompleted();
});
toolbar.Items = new UIBarButtonItem[] {
new UIBarButtonItem (UIBarButtonSystemItem.FlexibleSpace),
doneButton
};
this.Control.InputAccessoryView = toolbar;
}
}
but my question is how can we add this keyboard behavior on a Xamarin prompt dialog.
await DisplayPromptAsync("Title", "Content", keyboard: Keyboard.Numeric);

Answer 1

If you want to customize the Keyboard of AlertView in iOS , you could implement it by using DependencyService
in Forms
create a Interface
public interface IDisplayPrompt
{
void DisplayPrompt(string Title,string Content,Keyboard keyboard,Action<string> SubmitAction,Action CancelAction);
}
in iOS
using System;
using app55;
using app55.iOS;
using Xamarin.Forms;
using UIKit;
using System.Drawing;
[assembly: Dependency(typeof(DisplayPromptImplement))]
namespace app55.iOS
{
public class DisplayPromptImplement:IDisplayPrompt
{
public DisplayPromptImplement()
{
}
public void DisplayPrompt(string Title, string Content, Keyboard keyboard, Action<string> SubmitAction, Action CancelAction)
{
UIAlertController alertController = UIAlertController.Create(Title,Content,UIAlertControllerStyle.Alert);
UIAlertAction OKAction = UIAlertAction.Create("OK",UIAlertActionStyle.Default,(action)=> {
//click OK Button
var content = alertController.TextFields[0].Text;
SubmitAction.Invoke(content);
});
UIAlertAction DismissAction = UIAlertAction.Create("Cancel", UIAlertActionStyle.Cancel, (action) => {
//click Cancel Button
CancelAction.Invoke();
});
alertController.AddTextField((field)=> {
if (keyboard == Keyboard.Numeric)
field.KeyboardType = UIKeyboardType.NumberPad;
AddDoneButton(field);
});
alertController.AddAction(OKAction);
alertController.AddAction(DismissAction);
UIApplication.SharedApplication.KeyWindow.RootViewController.PresentViewController(alertController,true,null);
}
protected void AddDoneButton(UITextField field)
{
var toolbar = new UIToolbar(new RectangleF(0.0f, 0.0f, 50.0f, 44.0f));
var doneButton = new UIBarButtonItem(UIBarButtonSystemItem.Done, delegate
{
field.ResignFirstResponder();
});
toolbar.Items = new UIBarButtonItem[] {
new UIBarButtonItem (UIBarButtonSystemItem.FlexibleSpace),
doneButton
};
field.InputAccessoryView = toolbar;
}
}
}
Now in Forms we could invoked it like following
void Button_Clicked(System.Object sender, System.EventArgs e)
{
if(Device.RuntimePlatform=="iOS")
{
DependencyService.Get<IDisplayPrompt>().DisplayPrompt("Title", "Please Input Message", Keyboard.Numeric, (content) =>
{
/// get the content that you input
label.Text = content.ToString();
}, null);
}
else
{
// other platform
//...await DisplayPromptAsync
}
}
Screen Shot