闲来无事,倒腾了一个简单的silverlight视频播放器

近二日闲来无事，把silverlight的官方文档瞅了瞅，倒腾了一个简单的视频播放器，顺便也测试了下能否播放传说中的h.264，最终效果如下:

http://images.24city.com/jimmy/player/default.html

布局思路:

Grid做为最外层容器，分上中下三行

第一行为视频播放窗口，同时单击视频时"暂停"遮罩层也放在这一行，只不过默认不显示而已
第二行为进度条显示区，为了方便布局，在这一行用StackPanel作子容器横向放置了二个控件(进度条和时间显示)
第三行为其它的控制按钮区，也是用StackPanel横向放置其它控件

实现的功能:

1.单击视频，暂停播放，再次单击则继续播放，原则就是利用鼠标单击事件控制Canvas的显示/隐藏以及调用MediaElement的Play(),Pause()方法
2.进度条与播放时间的同步，这里用到了Timer控件，每隔一定时间重新设置进度条的值
3.播放列表采用json字符串解析后绑定实现，同时选择列表的相关视频后，马上播放选择的视频
4.全屏功能
5.静音功能(其实还可以方便左右声道功能，只要不知道界面上怎么放，所以这一块功能没加上去)
6.缓冲以及加载进度的百分比进度显示
7.播放时，预先加载下一段视频(这一块好象效果不明显，主要是对silverlight的缓冲机制不清楚，期待大家共同探讨改进)

另:本示例中用的视频全部为mp4格式的h.264视频

其它不清楚的地方，基本上代码中都有注释

xaml代码：

 1<UserControl x:Class="Test.MainPage"
 2    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" 
 3    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
 4    xmlns:d="http://schemas.microsoft.com/expression/blend/2008" xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" 
 5    mc:Ignorable="d">
 6    <Grid x:Name="LayoutRoot" ShowGridLines="False"  >
 7
 8        <!--Grid布局：分成三行，第一行放视频窗口，第二行为进度条，第三行为其它控制按钮-->
 9        <Grid.ColumnDefinitions>
10            <ColumnDefinition Width="*"></ColumnDefinition>           
11        </Grid.ColumnDefinitions>
12
13        <Grid.RowDefinitions>
14            <RowDefinition Height="*"></RowDefinition>
15            <RowDefinition Height="22"></RowDefinition>
16            <RowDefinition Height="25"></RowDefinition>
17        </Grid.RowDefinitions>
18
19
20        <!--视频播放控件-->
21        <MediaElement x:Name="media" Source="" Grid.Row="0"  Grid.Column="0" CurrentStateChanged="Media_State_Changed" MediaEnded="media_MediaEnded" Cursor="Hand" MouseLeftButtonDown="media_MouseLeftButtonDown" BufferingProgressChanged="media_BufferingProgressChanged" DownloadProgressChanged="media_DownloadProgressChanged"></MediaElement>
22
23        <!--这里用一个Canvas来实现暂停时的遮盖效果-->
24        <Canvas Background="#AAFAEBD7"  Grid.Row="0" Grid.Column="0"  Cursor="Hand"  x:Name="canvas_Pause" MouseLeftButtonDown="Canvas_MouseLeftButtonDown" >
25            <Ellipse Height="200" Width="200" Stroke="AliceBlue" StrokeThickness="10" Canvas.Left="140" Canvas.Top="80"></Ellipse>
26            <Path Stretch="Fill" Stroke="AliceBlue" StrokeThickness="10" Height="98" Width="10" UseLayoutRounding="False" Canvas.Left="203" Canvas.Top="131" Data="M208,136 L208,224"/>
27            <Path Stretch="Fill" Stroke="AliceBlue" StrokeThickness="10" Height="98" Width="10" UseLayoutRounding="False" Canvas.Left="263" Canvas.Top="131" Data="M208,136 L208,224"/>
28
29            <TextBlock Canvas.Left="104" Canvas.Top="296" Foreground="White" >Made by 菩提树下的杨过(http://yjmyzz.cnblogs.com/)</TextBlock>
30        </Canvas>
31        
32        <MediaElement x:Name="mediaBuffer" Width="0" Grid.Column="0" Grid.Row="0" BufferingTime="0:0:10" IsMuted="True" AutoPlay="True"  ></MediaElement>
33
34        <!--第二行用一个StackPanel横向放了二个子控件，用于显示进度条和当前播放时间-->
35        <StackPanel Grid.Column="0" Grid.Row="1" Orientation="Horizontal"  HorizontalAlignment="Center" >
36            <Slider Height="20" Width="370" x:Name="sliderProgress" ValueChanged="sliderProgress_ValueChanged" Cursor="Hand" ></Slider>
37            <TextBlock Text="00:00:00/00:00:00" Width="110" x:Name="txtTime"/>
38        </StackPanel>
39
40        <!--第三行同样用StackPanel横向放置其它控制按钮-->
41        <StackPanel Grid.Column="0" Grid.Row="2" Orientation="Horizontal" HorizontalAlignment="Center" >
42            <Button Click="PlayMedia"  Content="||" Width="25" Height="25" x:Name="btnPlay" Cursor="Hand" />
43            <Button Click="StopMedia"  Content="■" Width="25" Height="25" x:Name="btnStop" Cursor="Hand"/>
44            <TextBlock x:Name="txtProgress"   FontSize="12" Width="90" Text="缓冲中100%" Height="25" TextAlignment="Center" Margin="3,0"  Padding="0,6,0,0"  ></TextBlock>
45            <ComboBox x:Name="cboList" SelectionChanged="cboList_SelectionChanged" Height="25" Width="232">
46            
47            </ComboBox>
48            <Button Content="静" Width="25" Height="25" Margin="3,0" x:Name="btnVoice" Click="btnVoice_Click" Cursor="Hand"></Button>
49            <Slider Height="25" Width="50" x:Name="sliderVoice" Maximum="1" Minimum="0" ValueChanged="sliderVoice_ValueChanged" Value="0.5" Cursor="Hand" ></Slider>
50            <Button Content="全" Width="20" Height="25" Cursor="Hand" x:Name="btnFull" Click="btnFull_Click"></Button>
51        </StackPanel>
52
53    </Grid>
54</UserControl>
55

后端cs代码：

  1using System;
  2using System.Collections.Generic;
  3using System.Json;
  4using System.Windows;
  5using System.Windows.Controls;
  6using System.Windows.Input;
  7using System.Windows.Interop;
  8using System.Windows.Threading;
  9
 10namespace Test
 11{
 12
 13
 14    public partial class MainPage : UserControl
 15    {
 16        private DispatcherTimer _timerPlay;
 17
 18        //实际应用中，以下字符串可通过wcf调用获得
 19        private string _medialist = "[{src:'http://task.24city.com/video/01.mp4',name:'苹果王手机第1段'},{src:'http://task.24city.com/video/02.mp4',name:'苹果王手机第2段'},{src:'http://task.24city.com/video/03.mp4',name:'苹果王手机第3段'},{src:'http://task.24city.com/video/04.mp4',name:'蔡依林-柠檬草的味道'},{src:'http://task.24city.com/video/05.mp4',name:'我也不知道是啥'},{src:'http://task.24city.com/video/06.mp4',name:'游戏宣传片段'}]";
 20
 21        List<MediaItem> _listMedia = null;
 22
 23        int _currentIndex = -1;//正在播放的元素索引
 24
 25
 26        public MainPage()
 27        {
 28            InitializeComponent();
 29
 30            //解析Json
 31            JsonValue _jsValue = JsonArray.Parse(_medialist);
 32
 33            if (_jsValue.Count > 0)
 34            {
 35                _listMedia = new List<MediaItem>(_jsValue.Count);
 36
 37                for (int i = 0; i < _jsValue.Count; i++)
 38                {
 39                    _listMedia.Add(new MediaItem() { src = _jsValue[i]["src"], name = _jsValue[i]["name"] });
 40                }
 41
 42                _currentIndex = 0;//默认从第一个开始播放
 43                media.Source = new Uri(_listMedia[_currentIndex].src);                
 44
 45                cboList.ItemsSource = _listMedia;
 46                cboList.DisplayMemberPath = "name";
 47                cboList.SelectedIndex = _currentIndex;
 48
 49
 50                this._timerPlay = new DispatcherTimer();
 51                this._timerPlay.Interval = new TimeSpan(0, 0, 0, 0, 100);
 52                this._timerPlay.Tick += new EventHandler(timer_Tick);
 53                this._timerPlay.Start();
 54            }
 55
 56
 57            App.Current.Host.Content.FullScreenChanged += new EventHandler(Content_FullScreenChanged);
 58
 59
 60        }
 61
 62        /**//// <summary>
 63        /// timer触发时，设置进度条与播放时间同步
 64        /// </summary>
 65        /// <param name="sender"></param>
 66        /// <param name="e"></param>
 67        void timer_Tick(object sender, EventArgs e)
 68        {
 69            this.sliderProgress.Maximum = this.media.NaturalDuration.TimeSpan.TotalSeconds;
 70
 71            this.sliderProgress.ValueChanged -= new RoutedPropertyChangedEventHandler<double>(sliderProgress_ValueChanged);
 72
 73            this.sliderProgress.Value = this.media.Position.TotalSeconds;
 74
 75            this.sliderProgress.ValueChanged += new RoutedPropertyChangedEventHandler<double>(sliderProgress_ValueChanged);
 76
 77            this.txtTime.Text = media.Position.Hours.ToString().PadLeft(2, '0') + ":" + media.Position.Minutes.ToString().PadLeft(2, '0') + ":" + media.Position.Seconds.ToString().PadLeft(2, '0') + "/" + media.NaturalDuration.TimeSpan.Hours.ToString().PadLeft(2, '0') + ":" + media.NaturalDuration.TimeSpan.Minutes.ToString().PadLeft(2, '0') + ":" + media.NaturalDuration.TimeSpan.Seconds.ToString().PadLeft(2, '0');
 78        }
 79
 80        /**//// <summary>
 81        /// 显示播放状态
 82        /// </summary>
 83        /// <param name="sender"></param>
 84        /// <param name="e"></param>
 85        private void Media_State_Changed(object sender, EventArgs e)
 86        {
 87           
 88            if (_currentIndex >= 0)
 89            {
 90                MediaItem _currentMedia = _listMedia[_currentIndex];
 91
 92                switch (media.CurrentState)
 93                {
 94                    case System.Windows.Media.MediaElementState.AcquiringLicense:
 95                        txtProgress.Text = "加载许可证";
 96                       
 97                        break;
 98                    case System.Windows.Media.MediaElementState.Buffering:
 99                        txtProgress.Text = "缓冲中";                        
100                        break;
101                    case System.Windows.Media.MediaElementState.Closed:
102                        txtProgress.Text = "已关闭";
103                        break;
104                    case System.Windows.Media.MediaElementState.Individualizing:
105                        txtProgress.Text = "加载个性化设置";
106                        break;
107                    case System.Windows.Media.MediaElementState.Opening:
108                        txtProgress.Text = "加载中";
109                        break;
110                    case System.Windows.Media.MediaElementState.Paused:
111                        txtProgress.Text = "已暂停";
112                        break;
113                    case System.Windows.Media.MediaElementState.Playing:
114                        txtProgress.Text = "正在播放";  
115
116                        //预选缓冲下一段视频(不过在实际测试中，感觉这么干没啥明显效果，欢迎大家共同探讨如何提前缓冲下一段视频)
117                        if (_currentIndex + 1 > _listMedia.Count - 1)
118                        {
119                            mediaBuffer.Source = new Uri(_listMedia[0].src);
120                        }
121                        else 
122                        {
123                            mediaBuffer.Source = new Uri(_listMedia[_currentIndex + 1].src);
124                        }
125                     
126                        break;
127                    case System.Windows.Media.MediaElementState.Stopped:
128                        txtProgress.Text = "已停止";
129                        break;
130                    default:
131                        break;
132                }
133            }
134
135        }
136
137
138        /**//// <summary>
139        /// 停止播放
140        /// </summary>
141        /// <param name="sender"></param>
142        /// <param name="e"></param>
143        private void StopMedia(object sender, System.Windows.RoutedEventArgs e)
144        {
145            media.Stop();
146            btnPlay.Content = ">";
147
148        }
149
150       
151
152        /**//// <summary>
153        /// 播放/暂停
154        /// </summary>
155        /// <param name="sender"></param>
156        /// <param name="e"></param>
157        private void PlayMedia(object sender, System.Windows.RoutedEventArgs e)
158        {           
159
160            if (media.CurrentState == System.Windows.Media.MediaElementState.Paused || media.CurrentState == System.Windows.Media.MediaElementState.Stopped)
161            {
162                media.Play();
163                btnPlay.Content = "||";
164                canvas_Pause.Visibility = Visibility.Collapsed;
165                
166            }
167            else 
168            {
169                media.Pause();
170                btnPlay.Content = ">";
171                canvas_Pause.Visibility = Visibility.Visible;
172            }
173            
174        }
175
176        /**//// <summary>
177        /// 一段播放完毕后，自动跳到下一段
178        /// </summary>
179        /// <param name="sender"></param>
180        /// <param name="e"></param>
181        private void media_MediaEnded(object sender, System.Windows.RoutedEventArgs e)
182        {
183            _currentIndex++;
184
185            if (_currentIndex > _listMedia.Count - 1)
186            {
187                _currentIndex = 0;
188            }
189
190            media.Source = new Uri(_listMedia[_currentIndex].src);
191
192            cboList.SelectedIndex = _currentIndex;
193        }
194
195        /**//// <summary>
196        /// 下拉列表改变时，播放相关片段
197        /// </summary>
198        /// <param name="sender"></param>
199        /// <param name="e"></param>
200        private void cboList_SelectionChanged(object sender, SelectionChangedEventArgs e)
201        {
202            _currentIndex = cboList.SelectedIndex;
203            if (_currentIndex > _listMedia.Count - 1)
204            {
205                _currentIndex = 0;
206            }
207
208            media.Source = new Uri(_listMedia[_currentIndex].src);
209            canvas_Pause.Visibility = System.Windows.Visibility.Collapsed;
210            media.Position = new TimeSpan(0,0,0,0,0);
211            sliderProgress.Value = 0;
212        }
213
214        /**//// <summary>
215        /// 暂时Canvas点击后，隐藏Canvas，同时继续播放
216        /// </summary>
217        /// <param name="sender"></param>
218        /// <param name="e"></param>
219        private void Canvas_MouseLeftButtonDown(object sender, System.Windows.Input.MouseButtonEventArgs e)
220        {
221            canvas_Pause.Visibility = System.Windows.Visibility.Collapsed;
222            media.Play();
223        }
224
225        /**//// <summary>
226        /// 视频画面单击时，暂时播放
227        /// </summary>
228        /// <param name="sender"></param>
229        /// <param name="e"></param>
230        private void media_MouseLeftButtonDown(object sender, MouseButtonEventArgs e)
231        {
232            canvas_Pause.Visibility = System.Windows.Visibility.Visible;
233            media.Pause();
234        }
235
236        /**//// <summary>
237        /// 进度条拖动时，跳到相关位置
238        /// </summary>
239        /// <param name="sender"></param>
240        /// <param name="e"></param>
241        private void sliderProgress_ValueChanged(object sender, System.Windows.RoutedPropertyChangedEventArgs<double> e)
242        {
243            this.media.Position = new TimeSpan((long)(e.NewValue * 1000 * 1000 * 10));
244        }
245
246
247        //private void media_BufferingProgressChanged(object sender, RoutedEventHandler e) 
248        //{
249        //    txtTime.Text = "缓冲中" + media.BufferingProgress.ToString("F0") + "%";
250        //}
251
252        /**//// <summary>
253        /// 静音按钮的实现
254        /// </summary>
255        /// <param name="sender"></param>
256        /// <param name="e"></param>
257        private void btnVoice_Click(object sender, RoutedEventArgs e)
258        {
259            if (media.IsMuted)
260            {
261                media.IsMuted = false;
262                this.btnVoice.Content = "静";
263                sliderVoice.IsEnabled = true;
264            }
265            else 
266            {
267                media.IsMuted = true;
268                this.btnVoice.Content = "音";
269                sliderVoice.IsEnabled = false;
270            }
271
272        }
273
274        /**//// <summary>
275        /// 调整音量大小
276        /// </summary>
277        /// <param name="sender"></param>
278        /// <param name="e"></param>
279        private void sliderVoice_ValueChanged(object sender, RoutedPropertyChangedEventArgs<double> e)
280        {
281            if (sliderVoice == null)
282            {
283                return;
284            }
285            media.Volume = sliderVoice.Value;
286        }
287
288        private void btnFull_Click(object sender, RoutedEventArgs e)
289        {
290            Content contentObj = App.Current.Host.Content;
291            contentObj.IsFullScreen = !contentObj.IsFullScreen;
292
293           
294        }
295
296
297
298        private void Content_FullScreenChanged(object sender, EventArgs e) 
299        {
300            Content contentObj = App.Current.Host.Content;
301           
302            if (contentObj.IsFullScreen)
303            {
304                btnFull.Content = "退";
305            }
306            else
307            {
308                btnFull.Content = "全";
309            }
310        }
311
312        /**//// <summary>
313        /// 显示缓冲进度
314        /// </summary>
315        /// <param name="sender"></param>
316        /// <param name="e"></param>
317        private void media_BufferingProgressChanged(object sender, RoutedEventArgs e)
318        {
319            this.txtProgress.Text = "缓冲中" + (media.BufferingProgress*100).ToString("F0") + "%";
320            canvas_Pause.Visibility = Visibility.Visible;
321            if (media.BufferingProgress >= 1.0) 
322            {
323                canvas_Pause.Visibility = Visibility.Collapsed;
324                switch (media.CurrentState)
325                {
326                    case System.Windows.Media.MediaElementState.Buffering:
327                        txtProgress.Text = "缓冲中";
328                        break;
329                    case System.Windows.Media.MediaElementState.Closed:
330                        txtProgress.Text = "已关闭";
331                        break;
332                    case System.Windows.Media.MediaElementState.Paused:
333                        txtProgress.Text = "已暂停";
334                        break;
335                    case System.Windows.Media.MediaElementState.Playing:
336                        txtProgress.Text = "正在播放";
337                        break;
338                    case System.Windows.Media.MediaElementState.Stopped:
339                        txtProgress.Text = "已停止";
340                        break;
341                    default:
342                        txtProgress.Text = "就绪";
343                        break;
344                }
345            }
346        }
347
348        /**//// <summary>
349        /// 显示加载进度
350        /// </summary>
351        /// <param name="sender"></param>
352        /// <param name="e"></param>
353        private void media_DownloadProgressChanged(object sender, RoutedEventArgs e)
354        {
355            txtProgress.Text = "加载中" + (media.DownloadProgress * 100).ToString("F0") + "%";
356            if (media.DownloadProgress >= 1) 
357            {
358                switch (media.CurrentState)
359                {                   
360                    case System.Windows.Media.MediaElementState.Buffering:
361                        txtProgress.Text = "缓冲中";
362                        break;
363                    case System.Windows.Media.MediaElementState.Closed:
364                        txtProgress.Text = "已关闭";
365                        break;                  
366                    case System.Windows.Media.MediaElementState.Paused:
367                        txtProgress.Text = "已暂停";
368                        break;
369                    case System.Windows.Media.MediaElementState.Playing:
370                        txtProgress.Text = "正在播放";
371                        break;
372                    case System.Windows.Media.MediaElementState.Stopped:
373                        txtProgress.Text = "已停止";
374                        break;
375                    default:
376                        txtProgress.Text = "就绪";
377                        break;
378                }
379            }
380        }
381
382      
383
384
385    }
386
387
388    /**//// <summary>
389    /// 媒体元素Item自定义类
390    /// </summary>
391    public class MediaItem
392    {
393        public string src { set; get; }
394        public string name { set; get; }
395    }
396}
397