Save dialog - update file extension in dialog on type change

[WojTec]

How can I update file name in dialog on type change?

Delphi-Quellcode:

procedure OnTypeChange(...);
// Set DefaultExt here...
// Update file name:
SaveDialog.FileName := ChangeFileExt(SaveDialog.FileName, SaveDialog.DefaultExt);

But looks to not occur when type combobox is changed.

How can do it?