WPF DataGrid-DataGridCheckBoxColumn vs2010 c# .net

Question

I am working in vs2010. I have created a DataGrid which is bounded to ObservableCollection List;

the Class_CMD looks like this :

 public class Class_RetrieveCommand
{
    public string CMD { get; set; }
    public bool C_R_CMD { get; set; }
    public bool S_CMD { get; set; }
    public bool C_S_CMD { get; set; }
}

i have 4 delegates which i pass to another window, and this window needs to update the list during runtime. During the runtime i can see the string column of the grid updated all the time but the DataGridCheckBoxColumns are never updated.

the DataGrid -

<DataGrid Background="Transparent" x:Name="DataGrid_CMD" Width="450" MaxHeight="450" Height="Auto" ItemsSource="{Binding}" AutoGenerateColumns="True">

one of the delegates which updates the bool is -

 public void UpdateC_S_CMD(string Msg)
    {
        foreach (Class_CMD c in List.ToArray())
        {
            if (c.CMD.Equals(Msg))
                c.C_S_CMD = true;
        }
    }

I don't understand why the bool columns are not updated.... can anyone help please? thanks.

Answer 1

You should implement INotifyPropertyChanged in the Class_RetrieveCommand like this:

public class Class_RetrieveCommand : INotifyPropertyChanged
{
    private string _CMD;
    public string CMD 
    {
        get { return _CMD; } 
        set { _CMD = value; OnPropertyChanged("CMD"); }
    }

    ... similar for the other properties

    public event PropertyChangedEventHandler PropertyChanged;
    private void OnPropertyChanged(string propertyName)
    {
        var handler = PropertyChanged;
        if (handler != null)
        {
            handler(this, new PropertyChangedEventArgs(propertyName));
        }
    }
}

Unfortunately you can't use auto properties anymore then (except you resort to proxygenerators).

Answer 2

Your class Class_RetrieveCommand needs to implement the INotifyPropertyChanged interface. Otherwise the individual rows databound to the instances of the class don't know that the underlying properties have changed. If you change it to something like this, you should see the changes reflected in your grid:

public class Class_RetrieveCommand : INotifyPropertyChanged
{
    private bool _cRCmd;
    private bool _cSCmd;
    private string _cmd;
    private bool _sCmd;

    public string CMD
    {
        get { return _cmd; }
        set
        {
            _cmd = value;
            InvokePropertyChanged(new PropertyChangedEventArgs("CMD"));
        }
    }

    public bool C_R_CMD
    {
        get { return _cRCmd; }
        set
        {
            _cRCmd = value;
            InvokePropertyChanged(new PropertyChangedEventArgs("C_R_CMD"));
        }
    }

    public bool S_CMD
    {
        get { return _sCmd; }
        set
        {
            _sCmd = value;
            InvokePropertyChanged(new PropertyChangedEventArgs("S_CMD"));
        }
    }

    public bool C_S_CMD
    {
        get { return _cSCmd; }
        set
        {
            _cSCmd = value;
            InvokePropertyChanged(new PropertyChangedEventArgs("C_S_CMD"));
        }
    }

    #region INotifyPropertyChanged Members

    public event PropertyChangedEventHandler PropertyChanged;

    #endregion

    public void InvokePropertyChanged(PropertyChangedEventArgs e)
    {
        PropertyChangedEventHandler handler = PropertyChanged;
        if (handler != null)
        {
            handler(this, e);
        }
    }
}