lcl: allow form dragging by client area only if it is docked into docksite without dock manager

git-svn-id: trunk@20070 -

lcl/forms.pp

@@ -507,6 +507,7 @@ type
     procedure SetAutoSize(Value: Boolean); override;
   protected
     // drag and dock
+    procedure BeginAutoDrag; override;
     procedure DoDock(NewDockSite: TWinControl; var ARect: TRect); override;
     function GetFloating: Boolean; override;
     function GetDefaultDockCaption: String; override;

lcl/include/control.inc

@@ -71,11 +71,6 @@ end;
 ------------------------------------------------------------------------------}
 procedure TControl.BeginAutoDrag;
 begin
-{ TODO -cdocking : Automatic drag-dock never should start immediately.
-A docked control should not try to undock itself, at least not immediately.
-A docked control also should stay docked until it is really dropped into a different location,
-so that a docking mangager can detect and handle (abort) an drop into the old place.
- }
   BeginDrag(DragManager.DragImmediate, DragManager.DragThreshold);
 end;
 

lcl/include/customform.inc

@@ -1073,6 +1073,13 @@ begin
   inherited SetAutoSize(Value);
 end;
 
+procedure TCustomForm.BeginAutoDrag;
+begin
+  // allow form dragging only if it is docked into a site without DockManager
+  if (HostDockSite <> nil) and not HostDockSite.UseDockManager then
+    BeginDrag(False);
+end;
+
 class function TCustomForm.GetControlClassDefaultSize: TPoint;
 begin
   Result.X:=320;