Windows Phone Open URL(Website) Web Browser (WebBrowser,IsIndeterminate Progress)

Partial Public Class MainPage
    Inherits PhoneApplicationPage

    ' Constructor
    Public Sub New()
        InitializeComponent()

        ' AddHandler WebBrowser1
        AddHandler WebBrowser1.Navigating, AddressOf Me.WebBrowser1_Navigating ' Loading
        AddHandler WebBrowser1.Navigated, AddressOf Me.WebBrowser1_Navigated ' Load Finish
        ProgressBar1.Visibility = Visibility.Collapsed
    End Sub

    Private Sub btnGo_Click(sender As System.Object, e As System.Windows.RoutedEventArgs)
        Me.WebBrowser1.Source = New Uri(Me.txtURL.Text, UriKind.Absolute)
    End Sub

    Private Sub WebBrowser1_Navigating(sender As Object, e As Microsoft.Phone.Controls.NavigatingEventArgs)
        ProgressBar1.Visibility = Visibility.Visible
    End Sub

    Private Sub WebBrowser1_Navigated(sender As Object, e As System.Windows.Navigation.NavigationEventArgs)
        ProgressBar1.Visibility = Visibility.Collapsed
    End Sub

End Class

using System;
using System.Collections.Generic;
using System.Linq;
using System.Net;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Animation;
using System.Windows.Shapes;
using Microsoft.Phone.Controls;
using System.Windows.Threading;
using Microsoft.Phone.Shell;
using System.Windows.Media.Imaging;

namespace PhoneAppCS
{
    public partial class MainPage : PhoneApplicationPage
    {

        // Constructor
        public MainPage()
        {
            InitializeComponent();
            //  AddHandler WebBrowser1
            WebBrowser1.Navigating += this.WebBrowser1_Navigating;
            //  Loading
            WebBrowser1.Navigated += this.WebBrowser1_Navigated;
            //  Load Finish
            ProgressBar1.Visibility = Visibility.Collapsed;

        }

        private void btnGo_Click(object sender, System.Windows.RoutedEventArgs e)
        {
            this.WebBrowser1.Source = new Uri(this.txtURL.Text, UriKind.Absolute);
        }

        private void WebBrowser1_Navigating(object sender, Microsoft.Phone.Controls.NavigatingEventArgs e)
        {
            ProgressBar1.Visibility = Visibility.Visible;
        }

        private void WebBrowser1_Navigated(object sender, System.Windows.Navigation.NavigationEventArgs e)
        {
            ProgressBar1.Visibility = Visibility.Collapsed;
        }

    }
}