启动窗口没有关闭- WPF

我有一个带有进度条的闪屏，一旦加载完成，主窗口应该打开。然而，主窗口根本不会打开，即使在进度条完全加载后，启动窗口仍然存在。怎么了?

在App.xaml中，我设置了StartupUri="SplashWindow.xaml"

启动窗口代码:

using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Shapes;
using System.Threading;
using System.Windows.Media.Animation;
namespace Project_1
{
/// <summary>
/// Interaction logic for SplashWindow.xaml
/// </summary>
public partial class SplashWindow : Window
{
    public SplashWindow()
    {
        this.InitializeComponent();

       Duration duration = new Duration(System.TimeSpan.FromSeconds(10));
       DoubleAnimation doubleanimation = new     DoubleAnimation(splash_load.Maximum, duration);
       splash_load.BeginAnimation(ProgressBar.ValueProperty, doubleanimation); 
        if (splash_load.Value==100) //If progress bar (Name = "splash_load") loads completely
        {
        // Close splash window
        this.Close();
        // Open main window
        var mw = new revised_mainwindow();
        mw.Show();
        }
        // Insert code required on object creation below this point.
    }   
}
}