WPF仅绘制4张图像（使用C＃和XAML）

Question

I'm trying to customize a digital photo frame program template I found on MSDN but I found that it only shows 4 images at the max. If I add a 5th image to the ArrayList, the entire screen goes blank.

Does anyone know what's going on and why any images after the 4th added to the ArrayList will cause the image to disappear and window to blank out?

[post edit: included full source]

C# source:

using System;
using System.Collections.Generic;
using System.Windows;
using System.Windows.Media.Animation;
using System.Windows.Media.Imaging;

namespace CSWPFAnimatedImage
{
    /// <summary>
    /// Interaction logic for Window1.xaml
    /// </summary>
public partial class MainWindow : Window
{
    public MainWindow()
    {
        InitializeComponent();
    }

    int nextImageIndex;
    List<BitmapImage> images = new List<BitmapImage>();

    private void Window_Loaded(object sender, RoutedEventArgs e)
    {
        // Initialize the images collection
        images.Add(new BitmapImage(new Uri("Images/image1.jpg", UriKind.Relative)));
        images.Add(new BitmapImage(new Uri("Images/image2.jpg", UriKind.Relative)));
        images.Add(new BitmapImage(new Uri("Images/image3.jpg", UriKind.Relative)));
        images.Add(new BitmapImage(new Uri("Images/image4.jpg", UriKind.Relative)));

        nextImageIndex = 2;
    }

    private void VisbleToInvisible_Completed(object sender, EventArgs e)
    {
        // Change the source of the myImage1 to the next image to be shown
        // and increase the nextImageIndex
        this.myImage1.Source = images[nextImageIndex++];

        // If the nextImageIndex exceeds the top bound of the collection,
        // get it to 0 so as to show the first image next time
        if (nextImageIndex == images.Count)
        {
            nextImageIndex = 0;
        }

        // Get the InvisibleToVisible storyboard and start it
        Storyboard sb = this.FindResource("InvisibleToVisible") as Storyboard;
        sb.Begin(this);

    }

    private void InvisibleToVisible_Completed(object sender, EventArgs e)
    {
        // Change the source of the myImage2 to the next image to be shown
        // and increase the nextImageIndex
        this.myImage2.Source = images[nextImageIndex++];

        // If the nextImageIndex exceeds the top bound of the collection,
        // get it to 0 so as to show the first image next time
        if (nextImageIndex == images.Count)
        {
            nextImageIndex = 0;
        }

        // Get the VisibleToInvisible storyboard and start it
        Storyboard sb = this.FindResource("VisibleToInvisible") as Storyboard;
        sb.Begin(this);
    }  

}
}

XAML:

<Window x:Class="CSWPFAnimatedImage.MainWindow" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" Title="WPF Animated Image Sample" Height="300" Width="300" Loaded="Window_Loaded">
<Window.Resources>
    <Storyboard x:Key="VisibleToInvisible" Completed="VisbleToInvisible_Completed" >
        <DoubleAnimation Storyboard.TargetName="TransparentStop"
                        Storyboard.TargetProperty="Offset" To="0"  Duration="0:0:2"   />
        <DoubleAnimation Storyboard.TargetName="BlackStop"
                        Storyboard.TargetProperty="Offset" To="0" Duration="0:0:2"
                        />
    </Storyboard>
    <Storyboard x:Key="InvisibleToVisible" Completed="InvisibleToVisible_Completed">
        <DoubleAnimation Storyboard.TargetName="TransparentStop"
                        Storyboard.TargetProperty="Offset" To="1"  Duration="0:0:2"   />
        <DoubleAnimation Storyboard.TargetName="BlackStop"
                        Storyboard.TargetProperty="Offset" To="1" Duration="0:0:2"   />
    </Storyboard>
</Window.Resources>
<Window.Triggers>
    <EventTrigger RoutedEvent="Window.Loaded">
        <EventTrigger.Actions>
            <BeginStoryboard Storyboard="{StaticResource  VisibleToInvisible}"/>
        </EventTrigger.Actions>
    </EventTrigger>
</Window.Triggers>
<Grid Name="grid">        
    <Image x:Name="myImage2" Source="Images/image2.jpg" />
    <Image x:Name="myImage1" Source="Images/image1.jpg">
        <Image.OpacityMask>
            <LinearGradientBrush StartPoint="0,0" EndPoint="1,0">
                <GradientStop Offset="1" Color="Black" x:Name="BlackStop"/>
                <GradientStop Offset="1" Color="Transparent" x:Name="TransparentStop"/>
            </LinearGradientBrush>
        </Image.OpacityMask>
    </Image>
</Grid> </Window>

Answer 1

here this works

images.Add(new BitmapImage(new Uri("Images/image1.jpg", UriKind.Relative)));

and this doesn't

images.Add(new BitmapImage(new Uri("D:\\image2jpg", UriKind.Relative)));

so. change it to

images.Add(new BitmapImage(new Uri("D:\\image2jpg", UriKind.Absolute)));

It works when you copy an image from somewhere and paste it to the Images folder of the project and add it to the image list.