private bool?ShowDialog(IViewModel a_ownerViewModel, IDialogViewModel a_viewModel, Window a_dialog)
{
// Create dialog and set properties
a_dialog.Owner = a_ownerViewModel != null?FindOwnerWindow(a_ownerViewModel) : null;
a_dialog.DataContext = a_viewModel;
// Bind the closing event to the viewmodel.
CancelEventHandler cancelEventHandler = (a_sender, a_e) => a_e.Cancel = !a_viewModel.DialogIsClosing();
a_dialog.Closing += cancelEventHandler;
a_viewModel.DialogView = a_dialog as IDialogView;
try
{
// Show dialog
return(a_dialog.ShowDialog());
}
finally
{
a_viewModel.DialogClosed();
a_viewModel.DialogView = null;
a_dialog.Closing -= cancelEventHandler;
}
}