First of all, I'm sorry that my English is absurd.
I made a custom datepicker column.
If I type 'enter' when I want to finish editing the column,
it changes the value of its DataContext well, and the it updates the UI, too.
However, if I just click another cell or other UI element when editing is finished, (when the cell losts its focus)
It changes the value of its DataContext, but not the UI.
So the UI shows past value of the DataContext.
And when I click the cell again, the UI is updated.
I found that telerik's default date column works well.
But not mine... So It makes me sad.
Since I can't attach my solution in this forum,
I copied my source code.
public class SpeDateColumn : GridViewBoundColumnBase
public override FrameworkElement CreateCellEditElement(GridViewCell cell, object dataItem)
this.BindingTarget = RadDatePicker.SelectedDateProperty;
var picker = new RadDatePicker();
private Binding CreateValueBinding()
var valueBinding = new Binding();
valueBinding.Mode = BindingMode.TwoWay;
valueBinding.UpdateSourceTrigger = UpdateSourceTrigger.Default;
valueBinding.Path = new PropertyPath(this.DataMemberBinding.Path.Path);
Thank you in advance.