c# - Datagrid: User cannot edit or select a row -

i'm using datagrid in wpf display rows of users returned linq-sql expression in list:

private void admin_tab_gotfocus(object sender, routedeventargs e) {     if (dbmethods.checkdatabaseconnection())     {         using (pubsdatacontext db = new pubsdatacontext())         {             var allusers = new list<application_user>(from users in db.application_users                                                       select users);             users_datagrid.datacontext = allusers;         }     } } 

the users load fine, row row information intact. however, when rows left clicked row not become selected , there appears no event being passed. added in mousedown event , can capture right-clicks, never left click.

the xaml datagrid is:

<datagrid autogeneratecolumns="true" margin="6,6,6,215" name="users_datagrid"                                canuseraddrows="true" itemssource="{binding}" height="286" width="246"                               mouseleftbuttondown="users_datagrid_mouseleftbuttondown" mousedown="users_datagrid_mousedown"/> 

this identical code have separate datagrid on different window, both xaml , c#. here sample comparison:

xaml

<datagrid autogeneratecolumns="true" margin="1,136,1,207" name="studentlearningexperiences_datagrid" itemssource="{binding}"           horizontalscrollbarvisibility="visible" verticalscrollbarvisibility="visible" canuseraddrows="true">     <datagrid.contextmenu>         <contextmenu name="studentlearningexperiences_contextmenu">             <!--hack bug - not work button click <menuitem header="save" click="learningexperiencesave_btn_click" /> -->             <menuitem header="delete" click="delete_menuitem_click" />         </contextmenu>     </datagrid.contextmenu> </datagrid> 

c#

public void loadstudentlearningexperiences() {     if (dbmethods.checkdatabaseconnection())     {         using (pubsdatacontext db = new pubsdatacontext())         {             var completionlist = new list<learning_experience>(from s in db.learning_experiences                                                                s.student_id == student.student_id                                                                select s);             studentlearningexperiences_datagrid.datacontext = completionlist;         }     } } 

can find if have error, missed something, or advise experience? have referenced link cannot edit cells , wondering if sql server tables creating textblocks rather texboxes tables in sql server appear identical.

i experienced same issue , found each time click performed on control within tab "selectionchanged" event fires tab. put in check in code behind "selectionchanged" handler make sure code executes once per tab entry.