xaml - Databinding not working within resource dictionary -

i trying bind selecteditem property of listbox 2 textbox controls. these controls located in windows resource section. idea when entry in listbox gets selected 2 textbox controls display "blockname" , "blockhelptext" custom class. load listbox first clicking but1 button.

<window.resources> <stackpanel x:key="testsp" visibility="visible" datacontext="{binding elementname=lsbcommonblocks, path=selecteditem, diagnostics:presentationtracesources.tracelevel=high}">         <listbox x:name="lsbcommonblocks" displaymemberpath="blockname" selectionchanged="lb_sc"/>         <button x:name="but1" click="but1_click" content="button 1"/>         <textbox x:name="txt1" text="{binding path=blockname, diagnostics:presentationtracesources.tracelevel=high}"/>         <textbox x:name="txt2" text="{binding path=blockhelptext, diagnostics:presentationtracesources.tracelevel=high}"/>     </stackpanel> </window.resources>   <grid>   <contentcontrol visibility="visible"  x:name="contentworkarea" content="{staticresource testsp}"/> </grid> 

i have button who's click event ties itemsources property of listbox custom class blocktoolbar.

blocktoolbar[] blocks = { new blocktoolbar("block 1", "no block."),                               new blocktoolbar("block 2", "help."),                               new blocktoolbar("block 3", "help again.") };  private void but1_click(object sender, routedeventargs e)     {         stackpanel sp = (stackpanel)this.tryfindresource("testsp");         listbox lb = (listbox)logicaltreehelper.findlogicalnode(sp, "lsbcommonblocks");         lb.itemssource = blocks;     }  public class blocktoolbar : inotifypropertychanged {     private string blockname;     public string blockname     {         { return blockname; }         set {              blockname = value;             onpropertychanged(new propertychangedeventargs("blockname"));         }     }      private string blockhelptext;     public string blockhelptext     {         { return blockhelptext; }         set {              blockhelptext = value;             onpropertychanged(new propertychangedeventargs("blockhelptext"));         }     }      public blocktoolbar()     {         blockname = "";         blockhelptext = "";     }      public blocktoolbar(string blockname, string blockhelptext)     {         blockname = blockname;         blockhelptext = blockhelptext;     }      public event propertychangedeventhandler propertychanged;     public void onpropertychanged(propertychangedeventargs e)     {         if (propertychanged != null)             propertychanged(this, e);     } } 

databinding not work: textbox's txt1 , txt2 remain blank when click button. listbox populates ok. confirmed i'm able obtain blocktoolbar properties ok creating event on listbox.

visual studio (express) output window gives me following: system.windows.data error: 4 : cannot find source binding reference 'elementname=lsbcommonblocks'. bindingexpression:path=selecteditem; dataitem=null; target element 'stackpanel' (name=''); target property 'datacontext' (type 'object')

not sure i'm doing wrong. i'm kind new wpf.

if remove stackpanel resource (testsp) , replace contentcontrol testsp controls, databindings work. can bind txt1 , txt2 directly blocktoolbar object in resource can't seem bind txt1/txt2 selecteditem if in resource.

the reason i'm doing have complicated main window break seperate resourcedictionaries , call main window via contentcontrols. when couldn't work create simpler project try narrow down problem.

looks have create binding in code. made following changes , worked. thought tried before but...

private void but1_click(object sender, routedeventargs e)     {         stackpanel sp = (stackpanel)this.tryfindresource("testsp");         listbox lb = (listbox)logicaltreehelper.findlogicalnode(sp, "lsbcommonblocks");          binding mybinding = new binding();         mybinding.source = lb;         mybinding.path = new propertypath("selecteditem");         sp.setbinding(stackpanel.datacontextproperty, mybinding);          lb.itemssource = blocks;      }