ActivityExtensions.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
 
using Android.App;
using Android.Content;
using Android.OS;
using Android.Runtime;
using Android.Views;
using Android.Widget;
using Android.Views.InputMethods;
using Android.InputMethodServices;
using Android.Util;
 
namespace Mobile.Util
{
    public static class ActivityExtensions
    {
        public static void HideSoftKeyboard(this Activity activity)
        {
            new Handler().Post(delegate
            {
                var view = activity.CurrentFocus;
                if (view != null)
                {
                    InputMethodManager manager = (InputMethodManager)activity.GetSystemService(Context.InputMethodService);
                    manager.HideSoftInputFromWindow(view.WindowToken, 0);
                }
            });
        }
 
        public static void ShowSoftKeyboard(this Activity activity, View view = null, int delay = 200)
        {
            new Handler().PostDelayed(delegate
            {
                view = view ?? activity.CurrentFocus;
                if (view != null)
                {
                    if (view.HasFocus)
                        view.ClearFocus(); //bug fix for older versions of android
 
                    view.RequestFocus();
                    InputMethodManager manager = (InputMethodManager)activity.GetSystemService(Context.InputMethodService);
                    manager.ShowSoftInput(view, 0);
                }
            }, delay);
        }
    }
 
    public static class DialogExtensions
    {
        public static void HideSoftKeyboard(this Dialog dialog)
        {
            new Handler().Post(delegate
            {
                var view = dialog.CurrentFocus;
                if (view != null)
                {
                    InputMethodManager manager = (InputMethodManager)dialog.Context.GetSystemService(Context.InputMethodService);
                    manager.HideSoftInputFromWindow(view.WindowToken, 0);
                }
            });
        }
 
        public static void ShowSoftKeyboard(this Dialog dialog, View view = null, int delay = 200)
        {
            new Handler().PostDelayed(delegate
            {
                view = view ?? dialog.CurrentFocus;
                if (view != null)
                {
                    if (view.HasFocus)
                        view.ClearFocus(); //bug fix for older versions of android
 
                    view.RequestFocus();
                    InputMethodManager manager = (InputMethodManager)dialog.Context.GetSystemService(Context.InputMethodService);
                    manager.ShowSoftInput(view, 0);
                }
            }, delay);
        }     
    }
}