c# - Unable to refresh/update data grid after insert in Silverlight 4 -

i creating master detials silverlight page , having trouble updating datagrid after inserting new record. on top of page have text boxes enter information, when user clicks on save information automatically updated in database , displayed on datagrid without refreshing screen.

i able save information db no problems trying datagrid refresh new changes.

some of code behind save button below:

viewmodel.updateworkflow(summary, reason, email); loadoperation<document> lo = _context.load<document>(_context.getdocumentsquery(_docid), rtrefresh, null); 

the code rtrefresh:

private void rtrefresh(loadoperation<document> oloadoperation)     {                     if (oloadoperation.iscomplete)         {                                                                      viewmodel.getdocuments(_docid);         }     } 

i set viewmodel in xaml file as:

<controls:childwindow.resources>     <viewmodel:documentchildwindowviewmodel x:key="viewmodel" /> </controls:childwindow.resources> 

and viewmodel in code-behind:

viewmodel = resources["viewmodel"] documentchildwindowviewmodel; 

any appreciated, thank you.

i'm assuming datagrid bound ienumerable, maybe list<>? have tried using observablecollection<>? if bound observablecollection, let ui know when collection has changed.

<usercontrol x:class="silverlightapplication1.mainpage" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" xmlns:d="http://schemas.microsoft.com/expression/blend/2008" xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" xmlns:local="clr-namespace:silverlightapplication1" xmlns:data="clr-namespace:system.windows.controls;assembly=system.windows.controls.data" mc:ignorable="d" d:designheight="300" d:designwidth="400">  <usercontrol.datacontext>     <local:mainpage_viewmodel/> </usercontrol.datacontext>  <stackpanel>     <data:datagrid itemssource="{binding mycollection}">      </data:datagrid> </stackpanel> 

public class mainpage_viewmodel : inotifypropertychanged {     public observablecollection<object> mycollection     {         { return mycollection; }         set          {             if (mycollection != value)             {                 mycollection = value;                 onpropertychanged("mycollection");             }         }     }     private observablecollection<object> mycollection = new observablecollection<object>();      public void loaddata()     {         //execute load method, assign result mycollection     }      #region inotifypropertychanged members      public event propertychangedeventhandler propertychanged;      public void onpropertychanged(string propertyname)     {         if (propertychanged != null)         {             propertychanged(this, new propertychangedeventargs(propertyname));         }     }      #endregion }