Hide specific context menu in datagrid upon selected row wpf mvvm

Question

I got one issue on datagrid using WPF Mvvm. I set context menu on datagrid. here is my code.

 <DataGrid.ContextMenu>
                <ContextMenu IsEnabled="{Binding IsEnableCaseRefNo}" 
                             DataContext="{Binding PlacementTarget.DataContext, RelativeSource={RelativeSource Self}}"  >                                                       
                    <MenuItem Header=" - View Case" >
                        <i:Interaction.Triggers>
                            <i:EventTrigger EventName="Click">
                                <i:InvokeCommandAction Command="{Binding ContextCommand}" CommandParameter="VCD"></i:InvokeCommandAction>
                            </i:EventTrigger>
                        </i:Interaction.Triggers>
                    </MenuItem>
                    <MenuItem Header=" - Cheque" Visibility="{Binding SyncColumnVisibility, Converter={StaticResource visibilityConverter}}">
                        <i:Interaction.Triggers>
                            <i:EventTrigger EventName="Click">
                                <i:InvokeCommandAction Command="{Binding ContextCommand}" CommandParameter="BMK"></i:InvokeCommandAction>
                            </i:EventTrigger>
                        </i:Interaction.Triggers>
                    </MenuItem>
                    <MenuItem Header=" - Cash" Visibility="{Binding SyncColumnVisibility, Converter={StaticResource visibilityConverter}}">
                        <i:Interaction.Triggers>
                            <i:EventTrigger EventName="Click">
                                <i:InvokeCommandAction Command="{Binding ContextCommand}" CommandParameter="UNBMK"></i:InvokeCommandAction>
                            </i:EventTrigger>
                        </i:Interaction.Triggers>
                    </MenuItem>
               </ContextMenu>
            </DataGrid.ContextMenu>

I can show and hide context menu using visibility property. but now i want to enable/disable "-Cheque" context menu upon user selection. how can I disable 'Cheque' context menu when there are 100 over dollars in donate columns(that already shown in datagrid).

Here is my datagrid :

 <DataGrid Name="dgv" Background="WhiteSmoke" AutoGenerateColumns="False" CanUserAddRows="False" SelectedItem="{Binding SelectedItems,Mode=TwoWay,UpdateSourceTrigger=PropertyChanged}"
                      CanUserDeleteRows="False" Grid.Row="2" ItemsSource="{Binding LstcaseHearingModel,Mode=TwoWay,UpdateSourceTrigger=PropertyChanged}"                              
                      Grid.Column="2" HorizontalAlignment="Stretch" >

Thanks for any help. frog

Answer 1

1. Use SelectedCellsChanged event to get desired item.

     private void Dgrd_SelectedCellsChanged(object sender, SelectedCellsChangedEventArgs e) { SomeEntity item = (SomeEntity) Dgrd.CurrentItem; if(item.Donate > 100) viewModel.SyncColumnVisibility = Visibility.Collapsed; else viewModel.SyncColumnVisibility = Visibility.Visible; } 

As you are binding SelectedItem property to SelectedItems property of your ViewModel. So you can check the condition in its setter.