In der IDE

[implementation]

Nein, so geht's nicht. Aber so:

Delphi-Quellcode:

if csDesigning in ComponentState then
  WS := S_CHILD or LBS_SORT or WS_VISIBLE or WS_OVERLAPPEDWINDOW
      or WS_VSCROLL or WS_HSCROLL or WS_BORDER
else
  WS := S_CHILD or LBS_SORT;

SetWindowLong( ... WS ... );