我应该使用什么控件类型-图像,MediaElement等?


当前回答

添加到主响应,建议使用WpfAnimatedGif,你必须在最后添加以下行,如果你是交换图像与Gif,以确保动画实际执行:

ImageBehavior.SetRepeatBehavior(img, new RepeatBehavior(0));
ImageBehavior.SetRepeatBehavior(img, RepeatBehavior.Forever);

所以你的代码看起来像这样:

var image = new BitmapImage();
image.BeginInit();
image.UriSource = new Uri(fileName);
image.EndInit();
ImageBehavior.SetAnimatedSource(img, image);
ImageBehavior.SetRepeatBehavior(img, new RepeatBehavior(0));
ImageBehavior.SetRepeatBehavior(img, RepeatBehavior.Forever);

其他回答

我不确定这个问题是否已经解决,但最好的方法是使用WpfAnimatedGid库。这是非常容易,简单和直接的使用。它只需要2行XAML代码和后面的5行c#代码。

您将看到关于如何在那里使用它的所有必要细节。这也是我用来代替重新发明轮子的方法

我发布了一个扩展图像控件和使用Gif解码器的解决方案。gif解码器有一个frames属性。我动画FrameIndex属性。事件ChangingFrameIndex将源属性更改为与FrameIndex对应的帧(在解码器中)。我猜这个动图每秒有10帧。

class GifImage : Image
{
    private bool _isInitialized;
    private GifBitmapDecoder _gifDecoder;
    private Int32Animation _animation;

    public int FrameIndex
    {
        get { return (int)GetValue(FrameIndexProperty); }
        set { SetValue(FrameIndexProperty, value); }
    }

    private void Initialize()
    {
        _gifDecoder = new GifBitmapDecoder(new Uri("pack://application:,,," + this.GifSource), BitmapCreateOptions.PreservePixelFormat, BitmapCacheOption.Default);
        _animation = new Int32Animation(0, _gifDecoder.Frames.Count - 1, new Duration(new TimeSpan(0, 0, 0, _gifDecoder.Frames.Count / 10, (int)((_gifDecoder.Frames.Count / 10.0 - _gifDecoder.Frames.Count / 10) * 1000))));
        _animation.RepeatBehavior = RepeatBehavior.Forever;
        this.Source = _gifDecoder.Frames[0];

        _isInitialized = true;
    }

    static GifImage()
    {
        VisibilityProperty.OverrideMetadata(typeof (GifImage),
            new FrameworkPropertyMetadata(VisibilityPropertyChanged));
    }

    private static void VisibilityPropertyChanged(DependencyObject sender, DependencyPropertyChangedEventArgs e)
    {
        if ((Visibility)e.NewValue == Visibility.Visible)
        {
            ((GifImage)sender).StartAnimation();
        }
        else
        {
            ((GifImage)sender).StopAnimation();
        }
    }

    public static readonly DependencyProperty FrameIndexProperty =
        DependencyProperty.Register("FrameIndex", typeof(int), typeof(GifImage), new UIPropertyMetadata(0, new PropertyChangedCallback(ChangingFrameIndex)));

    static void ChangingFrameIndex(DependencyObject obj, DependencyPropertyChangedEventArgs ev)
    {
        var gifImage = obj as GifImage;
        gifImage.Source = gifImage._gifDecoder.Frames[(int)ev.NewValue];
    }

    /// <summary>
    /// Defines whether the animation starts on it's own
    /// </summary>
    public bool AutoStart
    {
        get { return (bool)GetValue(AutoStartProperty); }
        set { SetValue(AutoStartProperty, value); }
    }

    public static readonly DependencyProperty AutoStartProperty =
        DependencyProperty.Register("AutoStart", typeof(bool), typeof(GifImage), new UIPropertyMetadata(false, AutoStartPropertyChanged));

    private static void AutoStartPropertyChanged(DependencyObject sender, DependencyPropertyChangedEventArgs e)
    {
        if ((bool)e.NewValue)
            (sender as GifImage).StartAnimation();
    }

    public string GifSource
    {
        get { return (string)GetValue(GifSourceProperty); }
        set { SetValue(GifSourceProperty, value); }
    }

    public static readonly DependencyProperty GifSourceProperty =
        DependencyProperty.Register("GifSource", typeof(string), typeof(GifImage), new UIPropertyMetadata(string.Empty, GifSourcePropertyChanged));

    private static void GifSourcePropertyChanged(DependencyObject sender, DependencyPropertyChangedEventArgs e)
    {
        (sender as GifImage).Initialize();
    }

    /// <summary>
    /// Starts the animation
    /// </summary>
    public void StartAnimation()
    {
        if (!_isInitialized)
            this.Initialize();

        BeginAnimation(FrameIndexProperty, _animation);
    }

    /// <summary>
    /// Stops the animation
    /// </summary>
    public void StopAnimation()
    {
        BeginAnimation(FrameIndexProperty, null);
    }
}

使用示例(XAML):

<controls:GifImage x:Name="gifImage" Stretch="None" GifSource="/SomeImage.gif" AutoStart="True" />

我也搜索了一下,在旧MSDN论坛的一个帖子里找到了几个不同的解决方案。(链接不再工作,所以我删除了它)

最简单的执行似乎是使用WinForms PictureBox控件,并像这样(从线程中更改了一些东西,大部分是相同的)。

添加对System.Windows的引用。窗体,WindowsFormsIntegration和系统。首先绘制你的项目。

<Window x:Class="GifExample.Window1"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:wfi="clr-namespace:System.Windows.Forms.Integration;assembly=WindowsFormsIntegration"
    xmlns:winForms="clr-namespace:System.Windows.Forms;assembly=System.Windows.Forms"
    Loaded="Window_Loaded" >
    <Grid>
        <wfi:WindowsFormsHost>
            <winForms:PictureBox x:Name="pictureBoxLoading">
            </winForms:PictureBox>
        </wfi:WindowsFormsHost>
    </Grid>
</Window >

然后在Window_Loaded处理程序中,你会设置pictureBoxLoading。将ImageLocation属性设置为要显示的图像文件路径。

private void Window_Loaded(object sender, RoutedEventArgs e)
{
    pictureBoxLoading.ImageLocation = "../Images/mygif.gif";
}

在那个线程中提到了MediaElement控件,但也提到了它是一个相当笨重的控件,因此有许多替代方案,包括至少两个基于Image控件的自制控件,因此这是最简单的。

之前,我也遇到过类似的问题,我需要在你的项目中播放gif文件。我有两个选择:

使用WinForms中的PictureBox 使用第三方库,如codeplex.com的WPFAnimatedGif。

带有PictureBox的版本不适合我,而且项目不能为它使用外部库。所以我通过ImageAnimator的帮助,通过Bitmap为自己制作了它。因为,标准的BitmapImage不支持gif文件的回放。

完整的例子:

XAML

<Window x:Class="PlayGifHelp.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        Title="MainWindow" Height="350" Width="525" Loaded="MainWindow_Loaded">

    <Grid>
        <Image x:Name="SampleImage" />
    </Grid>
</Window>

后面的代码

public partial class MainWindow : Window
{
    public MainWindow()
    {
        InitializeComponent();
    }

    Bitmap _bitmap;
    BitmapSource _source;

    private BitmapSource GetSource()
    {
        if (_bitmap == null)
        {
            string path = Directory.GetCurrentDirectory();

            // Check the path to the .gif file
            _bitmap = new Bitmap(path + @"\anim.gif");
        }

        IntPtr handle = IntPtr.Zero;
        handle = _bitmap.GetHbitmap();

        return Imaging.CreateBitmapSourceFromHBitmap(handle, IntPtr.Zero, Int32Rect.Empty, BitmapSizeOptions.FromEmptyOptions());
    }

    private void MainWindow_Loaded(object sender, RoutedEventArgs e)
    {
        _source = GetSource();
        SampleImage.Source = _source;
        ImageAnimator.Animate(_bitmap, OnFrameChanged);
    }

    private void FrameUpdatedCallback()
    {
        ImageAnimator.UpdateFrames();

        if (_source != null)
        {
            _source.Freeze();
        }

        _source = GetSource();

        SampleImage.Source = _source;
        InvalidateVisual();
    }

    private void OnFrameChanged(object sender, EventArgs e)
    {
        Dispatcher.BeginInvoke(DispatcherPriority.Normal, new Action(FrameUpdatedCallback));
    }
}

位图不支持URI指令,所以我从当前目录加载。gif文件。

这是我的动画图像控制版本。您可以使用标准属性Source来指定图像源。我进一步改进了它。我是俄罗斯人,项目是俄罗斯的,所以评论也是俄语。但是无论如何,你应该能够理解没有注释的一切。:)

/// <summary>
/// Control the "Images", which supports animated GIF.
/// </summary>
public class AnimatedImage : Image
{
    #region Public properties

    /// <summary>
    /// Gets / sets the number of the current frame.
    /// </summary>
    public int FrameIndex
    {
        get { return (int) GetValue(FrameIndexProperty); }
        set { SetValue(FrameIndexProperty, value); }
    }

    /// <summary>
    /// Gets / sets the image that will be drawn.
    /// </summary>
    public new ImageSource Source
    {
        get { return (ImageSource) GetValue(SourceProperty); }
        set { SetValue(SourceProperty, value); }
    }

    #endregion

    #region Protected interface

    /// <summary>
    /// Provides derived classes an opportunity to handle changes to the Source property.
    /// </summary>
    protected virtual void OnSourceChanged(DependencyPropertyChangedEventArgs aEventArgs)
    {
        ClearAnimation();

        BitmapImage lBitmapImage = aEventArgs.NewValue as BitmapImage;

        if (lBitmapImage == null)
        {
            ImageSource lImageSource = aEventArgs.NewValue as ImageSource;
            base.Source = lImageSource;
            return;
        }

        if (!IsAnimatedGifImage(lBitmapImage))
        {
            base.Source = lBitmapImage;
            return;
        }

        PrepareAnimation(lBitmapImage);
    }

    #endregion

    #region Private properties

    private Int32Animation Animation { get; set; }
    private GifBitmapDecoder Decoder { get; set; }
    private bool IsAnimationWorking { get; set; }

    #endregion

    #region Private methods

    private void ClearAnimation()
    {
        if (Animation != null)
        {
            BeginAnimation(FrameIndexProperty, null);
        }

        IsAnimationWorking = false;
        Animation = null;
        Decoder = null;
    }

    private void PrepareAnimation(BitmapImage aBitmapImage)
    {
        Debug.Assert(aBitmapImage != null);

        if (aBitmapImage.UriSource != null)
        {
            Decoder = new GifBitmapDecoder(
                aBitmapImage.UriSource,
                BitmapCreateOptions.PreservePixelFormat,
                BitmapCacheOption.Default);
        }
        else
        {
            aBitmapImage.StreamSource.Position = 0;
            Decoder = new GifBitmapDecoder(
                aBitmapImage.StreamSource,
                BitmapCreateOptions.PreservePixelFormat,
                BitmapCacheOption.Default);
        }

        Animation =
            new Int32Animation(
                0,
                Decoder.Frames.Count - 1,
                new Duration(
                    new TimeSpan(
                        0,
                        0,
                        0,
                        Decoder.Frames.Count / 10,
                        (int) ((Decoder.Frames.Count / 10.0 - Decoder.Frames.Count / 10) * 1000))))
                {
                    RepeatBehavior = RepeatBehavior.Forever
                };

        base.Source = Decoder.Frames[0];
        BeginAnimation(FrameIndexProperty, Animation);
        IsAnimationWorking = true;
    }

    private bool IsAnimatedGifImage(BitmapImage aBitmapImage)
    {
        Debug.Assert(aBitmapImage != null);

        bool lResult = false;
        if (aBitmapImage.UriSource != null)
        {
            BitmapDecoder lBitmapDecoder = BitmapDecoder.Create(
                aBitmapImage.UriSource,
                BitmapCreateOptions.PreservePixelFormat,
                BitmapCacheOption.Default);
            lResult = lBitmapDecoder is GifBitmapDecoder;
        }
        else if (aBitmapImage.StreamSource != null)
        {
            try
            {
                long lStreamPosition = aBitmapImage.StreamSource.Position;
                aBitmapImage.StreamSource.Position = 0;
                GifBitmapDecoder lBitmapDecoder =
                    new GifBitmapDecoder(
                        aBitmapImage.StreamSource,
                        BitmapCreateOptions.PreservePixelFormat,
                        BitmapCacheOption.Default);
                lResult = lBitmapDecoder.Frames.Count > 1;

                aBitmapImage.StreamSource.Position = lStreamPosition;
            }
            catch
            {
                lResult = false;
            }
        }

        return lResult;
    }

    private static void ChangingFrameIndex
        (DependencyObject aObject, DependencyPropertyChangedEventArgs aEventArgs)
    {
        AnimatedImage lAnimatedImage = aObject as AnimatedImage;

        if (lAnimatedImage == null || !lAnimatedImage.IsAnimationWorking)
        {
            return;
        }

        int lFrameIndex = (int) aEventArgs.NewValue;
        ((Image) lAnimatedImage).Source = lAnimatedImage.Decoder.Frames[lFrameIndex];
        lAnimatedImage.InvalidateVisual();
    }

    /// <summary>
    /// Handles changes to the Source property.
    /// </summary>
    private static void OnSourceChanged
        (DependencyObject aObject, DependencyPropertyChangedEventArgs aEventArgs)
    {
        ((AnimatedImage) aObject).OnSourceChanged(aEventArgs);
    }

    #endregion

    #region Dependency Properties

    /// <summary>
    /// FrameIndex Dependency Property
    /// </summary>
    public static readonly DependencyProperty FrameIndexProperty =
        DependencyProperty.Register(
            "FrameIndex",
            typeof (int),
            typeof (AnimatedImage),
            new UIPropertyMetadata(0, ChangingFrameIndex));

    /// <summary>
    /// Source Dependency Property
    /// </summary>
    public new static readonly DependencyProperty SourceProperty =
        DependencyProperty.Register(
            "Source",
            typeof (ImageSource),
            typeof (AnimatedImage),
            new FrameworkPropertyMetadata(
                null,
                FrameworkPropertyMetadataOptions.AffectsRender |
                FrameworkPropertyMetadataOptions.AffectsMeasure,
                OnSourceChanged));

    #endregion
}