Question

I’m currenty working on a DataGridView-extentsion with custom DataSource handling. If I bind a list to two normal System.Windows.Forms.DataGridView and select an item in dataGridView1, dataGridView2 automatically also sets the position to the item.

If I assign a BindingSource I can handle the PositionChanged event, but a Generic.List doesn’t have a CurrencyManager, so how does the dataGridView2 know the new position?

Answer 1

Finally i found the answer: BindingContext!

A simple example:

public class ModifiedCollection : BindingSource {
    BindingSource Source {get;set;}
    BindingManagerBase bmb;
    Control Parent;

    public ModifiedCollection(object Source, Control Parent) {
        if ((this.Source = Source as BindingSource) == null) {
            this.Source = new BindingSource();
            this.Source.DataSource = Source;
        }

        this.Source.ListChanged += new ListChangedEventHandler(Source_ListChanged);


        this.Parent = Parent;
        this.Parent.BindingContextChanged += new EventHandler(Parent_BindingContextChanged);
    }

    void Parent_BindingContextChanged(object sender, EventArgs e) {
        if (bmb != null) {
            bmb.PositionChanged -= bmb_PositionChanged;
        }
        if (Parent.FindForm().BindingContext.Contains(this.Source.DataSource)) {
            bmb = Parent.BindingContext[this.Source.DataSource];
            if (bmb != null) {
                bmb.PositionChanged += new EventHandler(bmb_PositionChanged);
            }
        }
    }
}