SnipperImages(Silverlight DEMO)控件设计之--CheckBox

　　　Rectangle：用于绘制CheckBox外方框

        Path：用于绘制选中时的"X"图形（当然也可以按自己的意愿任意绘制）

        TextBlock：用于显示文本（提示）

< ControlTemplate  xmlns ="http://schemas.microsoft.com/client/2007"
                 xmlns:x ="http://schemas.microsoft.com/winfx/2006/xaml"   >
     < Grid  x:Name ="Part_Root"  Width ="130"  Height ="30"  Background ="Transparent" >
       < Grid.ColumnDefinitions >
         < ColumnDefinition  Width ="30" />
         < ColumnDefinition  Width ="*" />
       </ Grid.ColumnDefinitions >
       < Rectangle  x:Name ="Part_Box"  Grid.Column ="0"  Width ='18'  Height ='18'  Stroke ='AliceBlue'
                 Margin ='2'  Fill ='Transparent' />
       < Path  x:Name ="Part_Check"  Grid.Column ="0"  Visibility ="Collapsed"  Stroke ='LightGreen'
                 StrokeThickness ='3'  IsHitTestVisible ='False'  Data ='M10,10 L20,20 M20,10 L10,20' />
       < TextBlock  x:Name ="Part_Text"  Grid.Column ="1"  Margin ="0,5,0,0"  Foreground ='Red'  FontSize ='12'
                 Text ='CheckBox' />
     </ Grid >     
</ ControlTemplate >

[TemplatePart(Name  =   " Part_Root " , Type  =   typeof (Panel))]
[TemplatePart(Name  =   " Part_Box " , Type  =   typeof (FrameworkElement))]
[TemplatePart(Name  =   " Part_Check " , Type  =   typeof (FrameworkElement))]
[TemplatePart(Name  =   " Part_Text " , Type  =   typeof (TextBlock))]
public   partial   class  CheckBox : Control
{
     public  CheckBox()
    {
         string  xaml  =  ResourceHelper.GetTemplate( this .GetType());
        ControlTemplate template  =  (ControlTemplate)XamlReader.Load(xaml);
         this .Template  =  template;
         this .ApplyTemplate();
    }

     ///   <summary>
     ///  绑定模板元素及相应事件
     ///   </summary>
     public   override   void  OnApplyTemplate()
    {
        Part_Root  =  (Panel)GetTemplateChild( " Part_Root " );
        Part_Box  =  (FrameworkElement)GetTemplateChild( " Part_Box " );
        Part_Check  =  (FrameworkElement)GetTemplateChild( " Part_Check " );
        Part_Text  =  (TextBlock)GetTemplateChild( " Part_Text " );
        Part_Box.MouseLeftButtonUp  +=   new  MouseButtonEventHandler(Part_Box_MouseLeftButtonUp);
    }

     #region  定义Check事件
     public   event  EventHandler CheckedChanged;
     protected   void  OnCheckedChanged()
    {
         if  (CheckedChanged  !=   null )
        {
            CheckedChanged( this ,  new  EventArgs());
        }
    }
     #endregion


     ///   <summary>
     ///  Check元素鼠标左键Up事件
     ///   </summary>
     ///   <param name="sender"></param>
     ///   <param name="e"></param>
     void  Part_Box_MouseLeftButtonUp( object  sender, MouseButtonEventArgs e)
    {
         if  (_isChecked) // 当在点选状态下点击时，则修改为“未选”状态
        {
            _isChecked  =   false ;
            Part_Check.Visibility  =  Visibility.Collapsed; // 让选中图标"X"为"不显示"
            OnCheckedChanged(); // 运行绑定的客户端事件
        }
         else 　 // 与上面操作相反
        {
            _isChecked  =   true ;
            Part_Check.Visibility  =  Visibility.Visible;
            OnCheckedChanged();
        }
    }

     private   bool  _isChecked  =   false ;
     ///   <summary>
     ///  当前控件的“选中”状态
     ///   </summary>
     public   bool  IsChecked
    {
         get  {  return  _isChecked; }
         set
        {
            _isChecked  =  value;
             if  (_isChecked)
            {
                Part_Check.Visibility  =  Visibility.Visible;
            }
             else
            {
                Part_Check.Visibility  =  Visibility.Collapsed;
            }
        }
    }
    
     ///   <summary>
     ///  Checkbox文本
     ///   </summary>
     public   string  Text
    {
         get  {  return  Part_Text.Text; }
         set  { Part_Text.Text  =  value; }
    }
 
     #region  UI元素定义
     private  Panel Part_Root;
     private  FrameworkElement Part_Box;
     private  FrameworkElement Part_Check;
     private  TextBlock Part_Text;
     #endregion
}

　 < ctl:CheckBox  x:Name ="cbFullscreen"  Text ="(全屏)复选 框"    CheckedChanged ="
                   OnFullscreenCheckedChanged" />

public  Page2()
{
    InitializeComponent();
     // 绑定全屏状态触发事件
    App.Current.Host.Content.FullScreenChanged  +=   new  EventHandler(Content_FullScreenChanged);
}

#region  CheckBox示例代码
void  OnFullscreenCheckedChanged( object  sender, EventArgs e)
{
    App.Current.Host.Content.IsFullScreen  =  cbFullscreen.IsChecked;
}

void  Content_FullScreenChanged( object  sender, EventArgs e)
{
     if  (App.Current.Host.Content.IsFullScreen  ==   true )
    {
        cbFullscreen.IsChecked  =   true ;
    }
     else
    {
        cbFullscreen.IsChecked  =   false ;
    }
}
#endregion