안녕하세요.
소스코드를 간략하게 추려서 추가로 질문 드립니다.

원하는 것은 이미지가 로딩중에 GIF 이미지를 띄워서 '로딩중..'으로 표현하는 것입니다.
구글링을 뒤져가며 더듬더듬 따라해본 방법은 BackgroundWorker, UI쓰레드, 비동기(Async/Await)등을 해보았습니다.
많은 가르침 부탁 드립니다!


# MainWindow.xaml.cs

namespace WpfApp1
{
    /// <summary>
    /// MainWindow.xaml에 대한 상호 작용 논리
    /// </summary>
    public partial class MainWindow : Window
    {
        public MainWindow()
        {
            InitializeComponent();
        }

        private void Button_Click(object sender, RoutedEventArgs e)
        {
            // GIF 이미지를 표현한 Window
            LoadingProcess loadingProcess;
            loadingProcess = new LoadingProcess();
            loadingProcess.Top = this.Top + (this.ActualHeight - loadingProcess.Height) / 2;
            loadingProcess.Left = this.Left + (this.ActualWidth - loadingProcess.Width) / 2;
            loadingProcess.Show();

            //이미지 로딩 호출
            ImageLoading();
        }

        private void ImageLoading()
        {
            this.Dispatcher.BeginInvoke(DispatcherPriority.Normal,
                (ThreadStart)delegate ()
                {
                    int imageWidth = 88;
                    WrapPanel_Images.Children.Clear();
                    DirectoryInfo di = new DirectoryInfo(@"C:\Users\dp\Desktop\TEST");
                    String fileFilters = "*.jpg|*.jpeg|*.png|*.gif|*.tiff|*.bmp";
                    String[] files = fileFilters.Split('|').SelectMany(searchPattern => Directory.GetFiles(@"C:\Users\dp\Desktop\TEST", searchPattern)).ToArray();

                    for (int i = 0; i < files.Length; i++)
                    {
                        BitmapImage bitmapImage = new BitmapImage();
                        bitmapImage.BeginInit();
                        bitmapImage.UriSource = new Uri(@files[i], UriKind.Absolute);
                        bitmapImage.DecodePixelWidth = 10;
                        bitmapImage.CacheOption = BitmapCacheOption.OnLoad;
                        bitmapImage.EndInit();

                        Image image = new Image();
                        image.Stretch = Stretch.Uniform;
                        image.Width = imageWidth;
                        image.Source = bitmapImage;


                        Border border = new Border();
                        border.BorderThickness = new Thickness(1);
                        border.BorderBrush = new SolidColorBrush(Color.FromRgb(41, 57, 86));
                        border.Margin = new Thickness(2, 2, 2, 2);
                        border.Width = imageWidth;
                        border.Height = imageWidth;
                        border.Child = image;

                        TextBlock imageName = new TextBlock();
                        imageName.Text = System.IO.Path.GetFileName(files[i]);
                        imageName.VerticalAlignment = VerticalAlignment.Center;
                        imageName.HorizontalAlignment = HorizontalAlignment.Center;
                        imageName.Margin = new Thickness(0, 0, 0, 10);
                        imageName.MaxWidth = imageWidth - 4;

                        DockPanel dockPanel = new DockPanel();
                        DockPanel.SetDock(border, Dock.Top);
                        DockPanel.SetDock(imageName, Dock.Bottom);
                        dockPanel.Children.Add(border);
                        dockPanel.Children.Add(imageName);

                        WrapPanel_Images.Children.Add(dockPanel);
                    }
                }
            );
        }
    }
}




# Main.Window.xaml
<Window x:Class="WpfApp1.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
        xmlns:local="clr-namespace:WpfApp1"
        mc:Ignorable="d"
        Title="MainWindow" Height="350" Width="525">
    <Grid>
        <DockPanel>
            <Grid DockPanel.Dock="Top">
                <Button Click="Button_Click" x:Name="button1">
                    Click
                </Button>
            </Grid>
            <Grid DockPanel.Dock="Bottom">
                <ScrollViewer HorizontalScrollBarVisibility="Disabled" VerticalScrollBarVisibility="Auto">
                    <WrapPanel x:Name="WrapPanel_Images" Orientation="Horizontal"/>
                </ScrollViewer>
            </Grid>
        </DockPanel>
    </Grid>
</Window>

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