基于Cairngorm的Silverlight开发 - part3

使用ModelLocator来管理视图

之前只是简单的介绍了一下ModelLocator的用法，在这里要把模型和视图结合起来，通过模型来来控制视图。在Silverlight中我们可以看到所有新建立的xaml都是继承自UserControl，所以在这里更新欢称视图为控件。 至此给出一个项目的结构图出来。这里我是习惯把从网上下载的第三方类库放在项目中一个Lib的目录下，如果有源码的话直接加入解决方案中也是可以的。

为控件创建DependencyProperty属性

创建了DependencyProperty后能更方便的和ModelLocator进行绑定。处理一些界面上的动画效果也能更加的灵活。 这里给出一个标准的代码 // Using a DependencyProperty as the backing store for TheName.           // This enables animation, styling, binding, etc         public static readonly DependencyProperty TheNameProperty =             DependencyProperty.Register("TheName",                                         typeof(string),                                         typeof(Page),                                         new PropertyMetadata("",                                           new PropertyChangedCallback(                                             OnTheNameChanged)));         static void OnTheNameChanged(object sender,                                      DependencyPropertyChangedEventArgs args)         {             // Get reference to self             Page source = (Page)sender;             // Add Handling Code             string newValue = (string)args.NewValue;         } 更多关于创建自定义用户控件的请查看winter-cn 前辈的《Silverlight 2 Customized Control 开发》 ，写的非常的详细。（我这里就不再去重复的发明轮子了）

创建一个会变色的控件

这里首先看Demo 学习是一个温故知新的过程，之前我写过一篇《动态创建Storyboard》这里就用上他再结合DependencyProperty做一个会变色的控件。 运用DependencyProperty结合Storyboard创建控件 public partial class BackGorund : UserControl     {         public byte R         {             get { return (byte)GetValue(RProperty); }             set { SetValue(RProperty, value); }         }         // Using a DependencyProperty as the backing store for R.           // This enables animation, styling, binding, etc         public static readonly DependencyProperty RProperty =             DependencyProperty.Register("R",                                         typeof(byte),                                         typeof(BackGorund),                                         new PropertyMetadata((byte)0,                                             new PropertyChangedCallback(OnRChanged)));         static void OnRChanged(object sender, DependencyPropertyChangedEventArgs args)         {             // Get reference to self             BackGorund source = (BackGorund)sender;             source.changeColor();         }         public byte G         {             get { return (byte)GetValue(GProperty); }             set { SetValue(GProperty, value); }         }         // Using a DependencyProperty as the backing store for G.           // This enables animation, styling, binding, etc         public static readonly DependencyProperty GProperty =             DependencyProperty.Register("G",                                         typeof(byte),                                         typeof(BackGorund),                                         new PropertyMetadata((byte)0,                                             new PropertyChangedCallback(OnGChanged)));         static void OnGChanged(object sender, DependencyPropertyChangedEventArgs args)         {             // Get reference to self             BackGorund source = (BackGorund)sender;             source.changeColor();         }         public byte B         {             get { return (byte)GetValue(BProperty); }             set { SetValue(BProperty, value); }         }         // Using a DependencyProperty as the backing store for B.           // This enables animation, styling, binding, etc         public static readonly DependencyProperty BProperty =             DependencyProperty.Register("B",                                         typeof(byte),                                         typeof(BackGorund),                                         new PropertyMetadata((byte)0,                                             new PropertyChangedCallback(OnBChanged)));         static void OnBChanged(object sender, DependencyPropertyChangedEventArgs args)         {             // Get reference to self             BackGorund source = (BackGorund)sender;             source.changeColor();         }         public void changeColor()         {             colorAnim.To = Color.FromArgb(255, R, G, B);             storyboard.Begin();         }         private ColorAnimation colorAnim;         private Storyboard storyboard;         public BackGorund()         {             InitializeComponent();             storyboard = new Storyboard();             Brush br = this.LayoutRoot.Background;             colorAnim = new ColorAnimation();             colorAnim.To = Color.FromArgb(255, R, G, B);             colorAnim.Duration = TimeSpan.FromSeconds(1);             colorAnim.RepeatBehavior = new RepeatBehavior(1);             colorAnim.AutoReverse = false;             Storyboard.SetTarget(colorAnim, br);             Storyboard.SetTargetProperty(colorAnim, new PropertyPath("Color"));             storyboard.Children.Add(colorAnim);             Resources.Add("colorsb", storyboard);             this.Loaded += new RoutedEventHandler(BackGorund_Loaded);         }     } 创建ModelLocator public class BackGroundModel : ModelLocator     {                  private static readonly BackGroundModel _instance = new BackGroundModel();         public static BackGroundModel Instance { get { return _instance; } }         static BackGroundModel()         {         }         private BackGroundModel()             : base()         {         }         private byte _R = (byte)0;         public byte R         {             get { return _R; }             set             {                 _R = value;                 NotifyPropertyChanged("R");             }         }         private byte _G = (byte)0;         public byte G         {             get { return _G; }             set             {                 _G = value;                 NotifyPropertyChanged("G");             }         }         private byte _B = (byte)0;         public byte B         {             get { return _B; }             set             {                 _B = value;                 NotifyPropertyChanged("B");             }         }     } 控件Load时绑定属性，通过模型来控制视图 void BackGorund_Loaded(object sender, RoutedEventArgs e)         {             this.DataContext = BackGroundModel.Instance;             Binding bindR = new Binding("R");             bindR.Mode = BindingMode.TwoWay;             this.SetBinding(RProperty, bindR);             Binding bindG = new Binding("G");             bindG.Mode = BindingMode.TwoWay;             this.SetBinding(GProperty, bindG);             Binding bindB = new Binding("B");             bindB.Mode = BindingMode.TwoWay;             this.SetBinding(BProperty, bindB);         } 提高效率 Shawn Wildermuth 写了一个Code Snippets能帮我们快速的创建DependencyProperty属性，具体用法与下载地址请访问这里 。我自己写了一个快速创建ModelLocator的Code Snippets，用法都是一样，点击这里 下载。

送上视频 ：） ViewManagerP1.wmv

基于Cairngorm的Silverlight开发 - part2