wpf - Conditional cell editing in xamDataGrid -

i'm using xamdatagrid. want disable cell status column, if value dbnull. issue seems fieldsettings, i'm not able pass correct value cell converter. here code :

xaml :

<window.resources>     <dbnullconverter:dbnulltobooleanconverter x:key="nulltobooleanconverter" /> </window.resources> <grid>     <dockpanel>         <igdp:xamdatagrid x:name="griddata" datasource="{binding path=tempdatatable}">             <igdp:xamdatagrid.fieldlayoutsettings>                 <igdp:fieldlayoutsettings autogeneratefields="true"/>              </igdp:xamdatagrid.fieldlayoutsettings>              <igdp:xamdatagrid.fieldsettings>                 <igdp:fieldsettings allowedit="true" />             </igdp:xamdatagrid.fieldsettings>              <igdp:xamdatagrid.fieldlayouts>                 <igdp:fieldlayout>                     <igdp:field name="status" label="status">                         <igdp:field.settings>                             <igdp:fieldsettings allowedit="{binding source={relativesource self}, path=self, converter={staticresource nulltobooleanconverter}}" />                         </igdp:field.settings>                     </igdp:field>                     <igdp:field name="rowid" />                     <igdp:field name="result" label="value" />                     <igdp:field name="hasrowbeenedited" label="edited ?">                         <igdp:field.settings>                             <igdp:fieldsettings editortype="{x:type igeditors:xamcheckeditor}"/>                         </igdp:field.settings>                     </igdp:field>                 </igdp:fieldlayout>             </igdp:xamdatagrid.fieldlayouts>         </igdp:xamdatagrid>     </dockpanel> </grid> 

edit :

the error in line :

<igdp:fieldsettings allowedit="{binding source={relativesource self}, path=self, converter={staticresource nulltobooleanconverter}}" /> 

viewmodel :

public class dbnullconverterviewmodel : inotifypropertychanged {     private datatable tempdatatable;     public datatable tempdatatable     {         { return tempdatatable; }         set         {             tempdatatable = value;             raisedpropertychanged("tempdatatable");         }     }      public dbnullconverterviewmodel()     {         tempdatatable = new datatable();         getvalue();     }      private void getvalue()     {         tempdatatable.columns.add(new datacolumn("rowid", typeof(int32)));         tempdatatable.columns.add(new datacolumn("status", typeof(string)));         tempdatatable.columns.add(new datacolumn("statusnew", typeof(string)));         tempdatatable.columns.add(new datacolumn("hasrowbeenedited", typeof(bool)));          datarow row = tempdatatable.newrow();         row["rowid"] = 1;         row["status"] = "active";         row["statusnew"] = "new";         row["hasrowbeenedited"] = true;         tempdatatable.rows.add(row);         tempdatatable.acceptchanges();          datarow row1 = tempdatatable.newrow();         row1["rowid"] = 2;         row1["status"] = dbnull.value;         row1["statusnew"] = null;         row1["hasrowbeenedited"] = dbnull.value;         tempdatatable.rows.add(row1);         tempdatatable.acceptchanges();          raisedpropertychanged("tempdatatable");      } } 

converter :

public class dbnulltobooleanconverter : ivalueconverter {     public object convert(object value, type targettype, object parameter, cultureinfo culture)     {         if (value == dbnull.value)             return false;          return true;     }      public object convertback(object value, type targettype, object parameter, cultureinfo culture)     {         throw new notimplementedexception();     } } 

imp : i'm looking pure viewmodel solution.

first of all, binding allowedit won't work because applies cells of column. need more local approach.

also, binding incorrect. should read that:

{binding path=dataitem[status], converter={staticresource nulltobooleanconverter}} 

there post @ infragistics tries achieve similar. in gist, need setting custom control template cellvaluepresenter , add trigger:

<controltemplate.triggers>     <datatrigger binding="{binding dataitem[status], converter={staticresource nulltobooleanconverter}}" value="true">       <setter property="igeditors:valueeditor.isreadonly" value="false" />     </datatrigger>   </controltemplate.triggers> 

additionally, derive xamdatagrid , add piece of functionality ensure isreadonly works intended:

protected override void oneditmodestarting(infragistics.windows.datapresenter.events.editmodestartingeventargs args) {     var cell = args.cell;         var celleditor = infragistics.windows.datapresenter.cellvaluepresenter.fromcell(cell).editor;     if (celleditor != null && !celleditor.isreadonly)         base.oneditmodestarting(args);     else args.cancel=true; } 

when setting custom control template cellvaluepresenter, need need include default implementation can find in %program files%\infragistics\netadvantage {version}\wpf\defaultstyles\datapresenter\datapresentergeneric_express.xaml @ <style targettype="{x:type igdp:cellvaluepresenter}">.