c# - wpf form does not redraw -

i have made plugin autodesk navisworks wpf. have form should filled in after mouse down event.

public override bool mousedown(...) {     ...     //wpf form     wpfcontrol wpf = new wpfcontrol();      //getproperty - method cleares items     //then creates tab control, tab items , fills gridview     wpf.getproperty();  } 

first time after initialization wpf form fills, not redraw. however, tab control, tab items , grid view changes in debug mode. can't understand why not redraw.

at same time programmatically added button getproperty method refreshes wpf form.

private void btnchoosetemp_click(object sender, routedeventargs e) {      getproperty(); }