豆瓣电台WP7客户端 开发记录7

由于歌曲名称可能超过屏幕宽度而显示不下，所以当歌曲名称长度大于屏幕宽度的时候滚动显示。

 这里主要用storyboard来完成，主要是silverlight的知识了。

 1                 <Canvas>

 2                       < Canvas.Resources >
 3                           < Storyboard  x:Name ="sb" >
 4                               < DoubleAnimation  x:Name ="animation"
 5                              Storyboard.TargetProperty ="(Canvas.Left)"
 6                              Storyboard.TargetName ="SongName"
 7                              Duration ="0:0:9"
 8                              RepeatBehavior ="Forever"   />
 9                           </ Storyboard >
10                       </ Canvas.Resources >
11                   < TextBlock   x:Name ="SongName"  FontSize ="24"    HorizontalAlignment ="Center"  Margin ="0,15,0,0"   />

12                 </Canvas> 

 

cs: 1  /// <summary>

 2           ///  歌曲名称滚动
 3           ///   </summary>
 4           private   void  SongNameMarquee()
 5          {
 6               this .sb.Stop();
 7               double  sysWidth  =  System.Windows.Application.Current.Host.Content.ActualWidth; // 屏幕宽度
 8               if  (sysWidth  <=   this .SongName.ActualWidth)
 9              {
10                  animation.From  =  sysWidth;
11                  animation.To  =   - this .SongName.ActualWidth  -  (sysWidth  -   360 )  /   2 ; // 360为Canvas宽度
12                   this .sb.Begin();
13              }
14               else
15              { // canvas居中
16                   this .SongName.SetValue(Canvas.LeftProperty,  180 - this .SongName.ActualWidth / 2 );
17              }
18 
19          }

 主要是计算几个点麻烦点 其他没什么。