checkbox in datagrid checked event not trigger wpf mvvm

Question

my checkbox checked event is totally not trigger at all. here is my datagrid code. How should i trigger Checked event in wpf mvvm.

<Window x:Class="EmployeeManager.View.DataGridDownload"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:i="http://schemas.microsoft.com/expression/2010/interactivity"
        xmlns:ei="http://schemas.microsoft.com/expression/2010/interactions"
        Title="DataGridDownload" Height="600" Width="790">
    <Grid>
        <DataGrid HorizontalAlignment="Left" ItemsSource="{Binding TransView}" AutoGenerateColumns="False" Margin="10,62,0,0" VerticalAlignment="Top" Height="497" Width="762">
            <DataGrid.Columns>
                <DataGridTextColumn Header="caseRefNo" Binding="{Binding caseRefNo}" />
                <DataGridTextColumn Header="subjMatr" Binding="{Binding subjMatr}" />
                <DataGridTextColumn Header="Download %" Binding="{Binding incValue}" />
                <DataGridTemplateColumn>
                    <DataGridTemplateColumn.CellTemplate>
                        <DataTemplate>
                            <CheckBox  
                                Content="Please Select" IsChecked="{Binding Path=IsSelected, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}">
                                <i:Interaction.Triggers>
                                    <i:EventTrigger EventName="Checked">
                                        <i:InvokeCommandAction Command="{Binding CheckCommand}" />
                                    </i:EventTrigger>
                                </i:Interaction.Triggers>
                            </CheckBox>
                        </DataTemplate>                        
                    </DataGridTemplateColumn.CellTemplate>
                </DataGridTemplateColumn>
                <DataGridTemplateColumn>
                    <DataGridTemplateColumn.CellTemplate>
                        <DataTemplate>
                            <Label Content="{Binding incValue,UpdateSourceTrigger=PropertyChanged}" Background="Red" Foreground="White" />
                        </DataTemplate>
                    </DataGridTemplateColumn.CellTemplate>
                </DataGridTemplateColumn>
            </DataGrid.Columns>
        </DataGrid>
        <Label Content="{Binding UpdatePercentage}" HorizontalAlignment="Left" Background="Blue" Foreground="White" Margin="10,10,0,0" VerticalAlignment="Top" Width="338" Height="30">
        </Label>
        <Button Content="Button" HorizontalAlignment="Left" Margin="672,20,0,0" VerticalAlignment="Top" Width="75"/>

    </Grid>
</Window>

Here is my view model

public class DataGridDownloadViewModel:BindableBase{
public ObservableCollection<tblTransaction> TransList 
{ get; private set; }
public DispatcherTimer dispatchTimer = new DispatcherTimer();
public CollectionView TransView 
{ get; private set; }

public DelegateCommand<object> CheckCommand { get; set; }

private String _UpdatePer;
public String UpdatePercentage
        {
            get { return _UpdatePer; }
            set { SetProperty(ref _UpdatePer, value); }
        }

private string _caseId;
public string CaseID
        {
            get { return _caseId; }
            set { SetProperty(ref _caseId, value); }
        }

private string _isChecked;
public string isChecked
        {
            get { return _isChecked; }
            set { SetProperty(ref _isChecked, value); }
        }

private bool CanExecute(object args)
        {
            return true;
        }

private void CheckBoxChecker(object args)
        {
            //Should Work Here
            // Totally not coming to this function
        }      

public DataGridDownloadViewModel(List<tblTransaction> model)
        {
            CheckCommand = new DelegateCommand<object>(CheckBoxChecker, CanExecute);

            dispatchTimer.Interval = TimeSpan.FromMilliseconds(3000); 
            dispatchTimer.Tick += dispatchTimer_Tick;
            BackGroundThread bgT = Application.Current.Resources["BackGroundThread"] as BackGroundThread;

            bgT.GetPercentChanged += (ss, ee) =>
            {
                UpdatePercentage = bgT.local_percentage.ToString();               
            };

            bgT.GetCaseID += (ss, ee) =>
            {
                CaseID = bgT.local_caseRef;
            };

            TransList =new ObservableCollection<tblTransaction>(model);
            TransView = GetTransCollectionView(TransList);
            TransView.Filter = OnFilterTrans;

            var tokenSource = new CancellationTokenSource();
            var token = tokenSource.Token;

            var cancellationTokenSource = new CancellationTokenSource();

            dispatchTimer.Start();

        }

private void dispatchTimer_Tick(object sender, EventArgs e)
        {
            UpdateDataGrid();
        }       

public void UpdateDataGrid()
        {           
                foreach (tblTransaction tran in TransList)
                {
                    if (tran.caseRefNo == CaseID)
                    {
                        tran.incValue = int.Parse(UpdatePercentage);

                    }
                    else
                    {
                        tran.incValue = tran.incValue;                      
                    }
                }

                TransView.Refresh();           
        }

bool OnFilterTrans(object item)
        {
            var trans = (tblTransaction)item;
            return true;           
        }

        public CollectionView GetTransCollectionView(ObservableCollection<tblTransaction> tranList)
        {
            return (CollectionView)CollectionViewSource.GetDefaultView(tranList);
        }
    }

Is it the correct way of doing it? why checkcommand is not trigger?

Edited

here is my model :

    public class tblTransaction
{
    public string caseRefNo { get;set;}
    public string subjMatr { get; set; }
    public int incValue { get; set; }
    public DateTime? longTime { get; set; }

    public bool IsSelected { get; set; }
}

Thanks

Answer 1

The code below worked for me without using the interactivity library like the answer above, just change the AncestorType property on the Command binding declaration according to your case, for me, I was using a UserControl , on the example above they used Window .

Good Luck!

<DataGridTemplateColumn Width="auto">
    <DataGridTemplateColumn.CellTemplate>
        <DataTemplate>
            <CheckBox x:Name="select" HorizontalAlignment="Center"
                      Command="{Binding DataContext.CheckCommand, RelativeSource={RelativeSource FindAncestor, AncestorType=UserControl}}"
                      IsChecked="{Binding Path=Selected, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}">
            </CheckBox>
        </DataTemplate>
    </DataGridTemplateColumn.CellTemplate>
</DataGridTemplateColumn>

Answer 2

Try the following:

<i:InvokeCommandAction Command="{Binding DataContext.CheckCommand, 
    RelativeSource={RelativeSource FindAncestor, AncestorType=Window}}" />