我应该使用什么控件类型-图像,MediaElement等?


当前回答

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" />

其他回答

我有这个问题,直到我发现在WPF4,你可以模拟自己的关键帧图像动画。首先,将你的动画分割成一系列图像,并将它们命名为“Image1.gif”,“Image2,gif”,等等。将这些映像导入您的解决方案资源中。我假设您将它们放在图像的默认资源位置。

您将使用Image控件。使用下面的XAML代码。我已经去掉了不重要的部分。

<Image Name="Image1">
   <Image.Triggers>
      <EventTrigger RoutedEvent="Image.Loaded"
         <EventTrigger.Actions>
            <BeginStoryboard>
               <Storyboard>
                   <ObjectAnimationUsingKeyFrames Duration="0:0:1" Storyboard.TargetProperty="Source" RepeatBehavior="Forever">
                      <DiscreteObjectKeyFrames KeyTime="0:0:0">
                         <DiscreteObjectKeyFrame.Value>
                            <BitmapImage UriSource="Images/Image1.gif"/>
                         </DiscreteObjectKeyFrame.Value>
                      </DiscreteObjectKeyFrames>
                     <DiscreteObjectKeyFrames KeyTime="0:0:0.25">
                        <DiscreteObjectKeyFrame.Value>
                           <BitmapImage UriSource="Images/Image2.gif"/>
                        </DiscreteObjectKeyFrame.Value>
                     </DiscreteObjectKeyFrames>
                     <DiscreteObjectKeyFrames KeyTime="0:0:0.5">
                        <DiscreteObjectKeyFrame.Value>
                           <BitmapImage UriSource="Images/Image3.gif"/>
                        </DiscreteObjectKeyFrame.Value>
                     </DiscreteObjectKeyFrames>
                     <DiscreteObjectKeyFrames KeyTime="0:0:0.75">
                        <DiscreteObjectKeyFrame.Value>
                           <BitmapImage UriSource="Images/Image4.gif"/>
                        </DiscreteObjectKeyFrame.Value>
                     </DiscreteObjectKeyFrames>
                     <DiscreteObjectKeyFrames KeyTime="0:0:1">
                        <DiscreteObjectKeyFrame.Value>
                           <BitmapImage UriSource="Images/Image5.gif"/>
                        </DiscreteObjectKeyFrame.Value>
                     </DiscreteObjectKeyFrames>
                  </ObjectAnimationUsingKeyFrames>
               </Storyboard>
            </BeginStoryboard>
         </EventTrigger.Actions>
      </EventTrigger>
   </Image.Triggers>
</Image>

我无法让这个问题最流行的答案(上面由达里奥提出)正常工作。结果是奇怪的、起伏不定的动画和奇怪的工件。 目前为止我找到的最佳解决方案: https://github.com/XamlAnimatedGif/WpfAnimatedGif

你可以用NuGet安装它

WpfAnimatedGif安装包

并使用它,在一个新的名称空间的窗口,你想添加gif图像,并使用它如下所示

<Window x:Class="MainWindow"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:gif="http://wpfanimatedgif.codeplex.com" <!-- THIS NAMESPACE -->
    Title="MainWindow" Height="350" Width="525">

<Grid>
    <!-- EXAMPLE USAGE BELOW -->
    <Image gif:ImageBehavior.AnimatedSource="Images/animated.gif" />

这个包非常简洁,你可以像下面这样设置一些属性

<Image gif:ImageBehavior.RepeatBehavior="3x"
       gif:ImageBehavior.AnimatedSource="Images/animated.gif" />

你也可以在你的代码中使用它:

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

编辑:Silverlight支持

根据josh2112的评论,如果你想在Silverlight项目中添加GIF动画支持,请使用github.com/XamlAnimatedGif/XamlAnimatedGif

我使用这个库:https://github.com/XamlAnimatedGif/WpfAnimatedGif

首先,将库安装到项目中(使用包管理器控制台):

    PM > Install-Package WpfAnimatedGif

然后,使用这个片段到XAML文件:

    <Window x:Class="WpfAnimatedGif.Demo.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:gif="http://wpfanimatedgif.codeplex.com"
        Title="MainWindow" Height="350" Width="525">
        <Grid>
            <Image gif:ImageBehavior.AnimatedSource="Images/animated.gif" />
        ...

希望能有所帮助。

来源:https://github.com/XamlAnimatedGif/WpfAnimatedGif

GifImage.Initialize()方法的小改进,该方法从GIF元数据中读取适当的帧定时。

    private void Initialize()
    {
        _gifDecoder = new GifBitmapDecoder(new Uri("pack://application:,,," + this.GifSource), BitmapCreateOptions.PreservePixelFormat, BitmapCacheOption.Default);

        int duration=0;
        _animation = new Int32AnimationUsingKeyFrames();
        _animation.KeyFrames.Add(new DiscreteInt32KeyFrame(0, KeyTime.FromTimeSpan(new TimeSpan(0))));
        foreach (BitmapFrame frame in _gifDecoder.Frames)
        {
            BitmapMetadata btmd = (BitmapMetadata)frame.Metadata;
            duration += (ushort)btmd.GetQuery("/grctlext/Delay");
            _animation.KeyFrames.Add(new DiscreteInt32KeyFrame(_gifDecoder.Frames.IndexOf(frame)+1, KeyTime.FromTimeSpan(new TimeSpan(duration*100000))));
        }            
         _animation.RepeatBehavior = RepeatBehavior.Forever;
        this.Source = _gifDecoder.Frames[0];            
        _isInitialized = true;
    }

我修改了迈克·艾希瓦的代码,让它运行得更好。你可以使用它与1帧jpg png bmp或多帧gif。如果你想绑定uri到控件,绑定UriSource属性,或者你想绑定任何内存流,你绑定Source属性,这是一个BitmapImage。

    /// <summary> 
/// Элемент управления "Изображения", поддерживающий анимированные GIF. 
/// </summary> 
public class AnimatedImage : Image
{
    static AnimatedImage()
    {
        DefaultStyleKeyProperty.OverrideMetadata(typeof(AnimatedImage), new FrameworkPropertyMetadata(typeof(AnimatedImage)));
    }

    #region Public properties

    /// <summary> 
    /// Получает/устанавливает номер текущего кадра. 
    /// </summary> 
    public int FrameIndex
    {
        get { return (int)GetValue(FrameIndexProperty); }
        set { SetValue(FrameIndexProperty, value); }
    }

    /// <summary>
    /// Get the BitmapFrame List.
    /// </summary>
    public List<BitmapFrame> Frames { get; private set; }

    /// <summary>
    /// Get or set the repeatBehavior of the animation when source is gif formart.This is a dependency object.
    /// </summary>
    public RepeatBehavior AnimationRepeatBehavior
    {
        get { return (RepeatBehavior)GetValue(AnimationRepeatBehaviorProperty); }
        set { SetValue(AnimationRepeatBehaviorProperty, value); }
    }

    public new BitmapImage Source
    {
        get { return (BitmapImage)GetValue(SourceProperty); }
        set { SetValue(SourceProperty, value); }
    }

    public Uri UriSource
    {
        get { return (Uri)GetValue(UriSourceProperty); }
        set { SetValue(UriSourceProperty, value); }
    }

    #endregion

    #region Protected interface

    /// <summary> 
    /// Provides derived classes an opportunity to handle changes to the Source property. 
    /// </summary> 
    protected virtual void OnSourceChanged(DependencyPropertyChangedEventArgs e)
    {
        ClearAnimation();
        BitmapImage source;
        if (e.NewValue is Uri)
        {
            source = new BitmapImage();
            source.BeginInit();
            source.UriSource = e.NewValue as Uri;
            source.CacheOption = BitmapCacheOption.OnLoad;
            source.EndInit();
        }
        else if (e.NewValue is BitmapImage)
        {
            source = e.NewValue as BitmapImage;
        }
        else
        {
            return;
        }
        BitmapDecoder decoder;
        if (source.StreamSource != null)
        {
            decoder = BitmapDecoder.Create(source.StreamSource, BitmapCreateOptions.DelayCreation, BitmapCacheOption.OnLoad);
        }
        else if (source.UriSource != null)
        {
            decoder = BitmapDecoder.Create(source.UriSource, BitmapCreateOptions.DelayCreation, BitmapCacheOption.OnLoad);
        }
        else
        {
            return;
        }
        if (decoder.Frames.Count == 1)
        {
            base.Source = decoder.Frames[0];
            return;
        }

        this.Frames = decoder.Frames.ToList();

        PrepareAnimation();
    }

    #endregion

    #region Private properties

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

    #endregion

    #region Private methods

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

        IsAnimationWorking = false;
        Animation = null;
        this.Frames = null;
    }

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

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

    private static void ChangingFrameIndex
        (DependencyObject dp, DependencyPropertyChangedEventArgs e)
    {
        AnimatedImage animatedImage = dp as AnimatedImage;

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

        int frameIndex = (int)e.NewValue;
        ((Image)animatedImage).Source = animatedImage.Frames[frameIndex];
        animatedImage.InvalidateVisual();
    }

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

    #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(BitmapImage),
            typeof(AnimatedImage),
            new FrameworkPropertyMetadata(
                null,
                FrameworkPropertyMetadataOptions.AffectsRender |
                FrameworkPropertyMetadataOptions.AffectsMeasure,
                OnSourceChanged));

    /// <summary>
    /// AnimationRepeatBehavior Dependency Property
    /// </summary>
    public static readonly DependencyProperty AnimationRepeatBehaviorProperty =
        DependencyProperty.Register(
        "AnimationRepeatBehavior",
        typeof(RepeatBehavior),
        typeof(AnimatedImage),
        new PropertyMetadata(null));

    public static readonly DependencyProperty UriSourceProperty =
        DependencyProperty.Register(
        "UriSource",
        typeof(Uri),
        typeof(AnimatedImage),
                new FrameworkPropertyMetadata(
                null,
                FrameworkPropertyMetadataOptions.AffectsRender |
                FrameworkPropertyMetadataOptions.AffectsMeasure,
                OnSourceChanged));

    #endregion
}

这是一个自定义控件。您需要在WPF应用程序项目中创建它,并在样式中删除模板覆盖。