How to add events to templated control in silverlight? -

bounty rewarded solid tutorial/learning resources regarding wiring events templated controls.

i have control template this:

<style targettype="local:datepicker">     <setter property="template">         <setter.value>             <controltemplate targettype="local:datepicker">                 <border background="{templatebinding background}"                         borderbrush="{templatebinding borderbrush}"                         borderthickness="{templatebinding borderthickness}" x:name="mydatepickercontentarea">                     <stackpanel orientation="vertical">                         <button x:name="mytestbutton" content="test button"  />                         <telerik:raddatepicker style="{staticresource visitsreporttextboxstyle}" foreground="#ffffff"  x:name="startdate" datetimewatermarkcontent="start date"/>                         <telerik:raddatepicker style="{staticresource visitsreporttextboxstyle}"  x:name="enddate" datetimewatermarkcontent="end date"/>                     </stackpanel>                 </border>             </controltemplate>         </setter.value>     </setter> </style> 

the c# template is:

public class datepicker : control  {      public static readonly dependencyproperty startdateselecteddateproperty = dependencyproperty.register("startdateselecteddateproperty", typeof(datetime), typeof(datepicker), null);     public datetime? startdateselecteddate { get; set; }       public datepicker()     {         this.defaultstylekey = typeof(datepicker);                  }        public override void onapplytemplate()     {         raddatepicker startdate = this.gettemplatechild("startdate") raddatepicker;         startdate.selectionchanged += new telerik.windows.controls.selectionchangedeventhandler(startdate_selectionchanged);         startdate.selecteddate = new datetime(2010, 01, 01);                     base.onapplytemplate();               }      void startdate_selectionchanged(object sender, telerik.windows.controls.selectionchangedeventargs e)     {         raddatepicker temp = (raddatepicker)sender;         startdateselecteddate = temp.selecteddate;     }   } 

my selectionchanged event doesn't fire , i'm not sure why. ideas ?

here example of using best practice sort of control think attempting build (see notes @ end explanations):-

[templatepart(name = datepicker.elementstartdate, type = typeof(raddatepicker))] [templatepart(name = datepicker.elementenddate, type = typeof(raddatepicker))] public class datepicker : control   {      public datepicker()      {          this.defaultstylekey = typeof(datepicker);                  }        #region template part names     private const string elementstartdate = "startdate";     private const string elementenddate = "enddate";     #endregion      #region template parts     private raddatepicker _startdate;      internal raddatepicker startdate     {         { return _startdate; }         private set          {             if (_startdate != null)             {                 _startdate.selectionchanged -= startdate_selectionchanged;             }              _startdate = value;              if (_startdate != null)             {                 _startdate.selectionchanged += startdate_selectionchanged;             }         }     }      private raddatepicker _enddate;      internal raddatepicker enddate     {         { return _enddate; }         private set          {             if (_enddate!= null)             {                 _enddate.selectionchanged -= enddate_selectionchanged;             }              _enddate= value;              if (_enddate!= null)             {                 _enddate.selectionchanged += enddate_selectionchanged;             }         }     }      #endregion      public static readonly dependencyproperty startdateselecteddateproperty =         dependencyproperty.register(             "startdateselecteddateproperty",              typeof(datetime?),              typeof(datepicker),              new propertymetadata(new datetime(2010, 01, 01)));      public datetime? startdateselecteddate     {         { return (datetime?)getvalue(startdateselecteddateproperty); }         set { setvalue(startdateselecteddateproperty)}      }      public static readonly dependencyproperty enddateselecteddateproperty =         dependencyproperty.register(             "enddateselecteddateproperty",              typeof(datetime?),              typeof(datepicker),              new propertymetadata(new datetime(2010, 01, 01)));      public datetime? enddateselecteddate      {         { return (datetime?)getvalue(enddateselecteddateproperty); }         set { setvalue(enddateselecteddateproperty)}      }      public override void onapplytemplate()      {          base.onapplytemplate();                     startdate = gettemplatechild(elementstartdate) raddatepicker;          enddate =  gettemplatechild(elementenddate) raddatepicker;      }       void startdate_selectionchanged(object sender, telerik.windows.controls.selectionchangedeventargs e)      {          // stuff startdate here     }       void enddate_selectionchanged(object sender, telerik.windows.controls.selectionchangedeventargs e)      {          // stuff enddate here     }      }  

the template xaml should like:-

<style targettype="local:datepicker">                                      <setter property="template">                                          <setter.value>                                              <controltemplate targettype="local:datepicker">                                                  <border background="{templatebinding background}"                                                          borderbrush="{templatebinding borderbrush}"                                                          borderthickness="{templatebinding borderthickness}" x:name="mydatepickercontentarea">                                                      <stackpanel orientation="vertical">                                                          <button x:name="mytestbutton" content="test button"  />                                                          <telerik:raddatepicker x:name="startdate"                             style="{staticresource visitsreporttextboxstyle}"                             foreground="#ffffff"                             datetimewatermarkcontent="start date"                             selecteddate="{templatebinding startdateselecteddate}"                          />                                                          <telerik:raddatepicker x:name="enddate"                             style="{staticresource visitsreporttextboxstyle}"                             datetimewatermarkcontent="end date"                             selecteddate="{templatebinding enddateselecteddate}"                         />                                                      </stackpanel>                                                  </border>                                              </controltemplate>                                          </setter.value>                                      </setter>                                  </style> 

some explanations

• a key problem original code had hadn't implemented dependency properties correctly. note properties use getvalue , setvalue, property meta data used assign default rather attempting set in in onapplytemplate.
• with properties correctly implemented template binding should work , in fact we're done far getting appears original intent, hence i've left out actual code in event handlers.
• create constants in code hold names of key template parts want interact with, allows name changes less expensive make.
• add templatepart attributes class indicate key elements code expects find, names should , base type expected have. allows designer re-template existing control, long declared template parts present somewher control should function correctly if ui radically altered.
• if need attach event handlers elements create field hold reference element , create property wrap round it. property setter should detach , attach event handlers see in code.
• make sure bae.onapplytemplate called in override of onapplytemplate can see quite straight forward assign above created properties.
• i don't have raddatepicker can't test, outstanding concern datetime? correct type selecteddate property. if improvement on microsoft offering seems have drop ball on typical data entry requirement.