DatePicker with placeholder in Xamarin Form

In Xamarin Form project create ExtendedDatePicker that Inherit the DatePicker Class.

ExtendedDatePicker.cs

using System;
using System.Collections.Generic;
using System.Text;
using Xamarin.Forms;
 
namespace Mechat.Renderer
{
    public class ExtendedDatePicker : DatePicker
    {
    }
}

Xamarin.Android

Then in Android Project Create the Class ExtendedDatePickerRenderer.cs that Inherit the DatePickerRenderer.

ExtendedDatePickerRenderer.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 Mechat.Droid.Renderer;
using Mechat.Renderer;
using Xamarin.Forms;
using Xamarin.Forms.Platform.Android;
 
[assembly:ExportRenderer(typeof(ExtendedDatePicker), typeof(ExtendedDatePickerRenderer))]
namespace Mechat.Droid.Renderer
{
   public class ExtendedDatePickerRenderer : DatePickerRenderer
    {
 
        public ExtendedDatePickerRenderer(Context context) : base(context)
        {
 
        }
        protected override void OnElementChanged(ElementChangedEventArgs<Xamarin.Forms.DatePicker> e)
        {
            base.OnElementChanged(e);
            if (Control != null)
            {
                Control.Text = "Select Birthdate";
            }
        }
    }
}

Xamarin.iOS

Then in iOS Project Create the Class ExtendedDatePickerRenderer.cs

that Inherit the DatePickerRenderer.

ExtendedHtmlLabelRenderer.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
 
using Foundation;
using Mechat.iOS.Renderer;
using Mechat.Renderer;
using UIKit;
using Xamarin.Forms;
using Xamarin.Forms.Platform.iOS;
 
[assembly: ExportRenderer(typeof(ExtendedDatePicker), typeof(ExtendedDatePickerRenderer))]
namespace Mechat.iOS.Renderer
{
  public class ExtendedDatePickerRenderer : DatePickerRenderer
    {
 
        protected override void OnElementChanged(ElementChangedEventArgs<DatePicker> e)
        {
            base.OnElementChanged(e);
            if (Control != null)
            {
                Control.Text = "Select Birthdate";
            }
        }
    }
}

Now implement this Renderer on Xamairn Page.

MainPage.xaml

<?xml version="1.0" encoding="utf-8" ?>
<ContentPage xmlns="http://xamarin.com/schemas/2014/forms"
             xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
             xmlns:d="http://xamarin.com/schemas/2014/forms/design"
             xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
             xmlns:xamAuth="xamarin.a"
             mc:Ignorable="d"
             xmlns:local="clr-namespace:Mechat.Renderer" 
             x:Class="Mechat.MainPage">
 
    <StackLayout Margin="10">
        <Label Text="Normal datepicker" />
        <DatePicker />
        <Label Text="Extended Date picker" />
        <local:ExtendedDatePicker />
    </StackLayout>
</ContentPage>

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