lcl: fix ListBox onChange call on win32 (mantis #0020324)

- notify TWS class about drag start
  - set csLButtonDown before BeginAutoDrag (there is no dependency in LCL for csLButtonDown in BeginAutoDrag so I see no reason to postpone it)
win32:
  - send TWM_LButtonUp to windows for ListBox if drag operation is started by mouse down

git-svn-id: trunk@42627 -

lcl/include/control.inc

@@ -2059,9 +2059,7 @@ begin
       LM_LBUTTONDOWN,
       LM_LBUTTONDBLCLK:
         begin
-          if FDragMode = dmAutomatic
+          Include(FControlState, csLButtonDown);
-          then begin
-            BeginAutoDrag;
           { The VCL holds up the mouse down for dmAutomatic
             and sends it, when it decides, if it is a drag operation or
             not.
@@ -2074,9 +2072,8 @@ begin
             For example: If we exit here, then mouse down on TTreeView does
               not work any longer under gtk.
           }
-            // VCL: exit;
+          if FDragMode = dmAutomatic then
-          end;
+            BeginAutoDrag;
-          Include(FControlState,csLButtonDown);
         end;
 
       LM_LBUTTONUP:

lcl/include/dragmanager.inc

@@ -652,6 +652,8 @@ begin
     FWaitForTreshold := not AImmediate;
     GetCursorPos(FStartPosition);
 
+    TWSControlClass(AControl.WidgetSetClass).DragStart(AControl, AImmediate);
+
     case AControl.DragKind of
       dkDrag: FPerformer := TDragPerformer.Create(Self, AControl);
       dkDock: FPerformer := TDockPerformer.Create(Self, AControl);

lcl/interfaces/win32/win32wsstdctrls.pp

@@ -114,6 +114,9 @@ type
           var Left, Top, Width, Height: integer; var SuppressMove: boolean); override;
     class function CreateHandle(const AWinControl: TWinControl;
           const AParams: TCreateParams): HWND; override;
+    class procedure DragStart(const AControl: TControl;
+       const Immediate: Boolean); override;
+
     class function GetIndexAtXY(const ACustomListBox: TCustomListBox; X, Y: integer): integer; override;
     class function GetItemIndex(const ACustomListBox: TCustomListBox): integer; override;
     class function GetItemRect(const ACustomListBox: TCustomListBox; Index: integer; var ARect: TRect): boolean; override;
@@ -635,6 +638,20 @@ begin
   Result := Params.Window;
 end;
 
+class procedure TWin32WSCustomListBox.DragStart(const AControl: TControl; const Immediate: Boolean);
+var
+  P: TPoint;
+begin
+  if csLButtonDown in AControl.ControlState then
+  begin
+    // if drag is called by mouse down then we need to complete it with mouse up
+    // since in other case we will not get the change event called
+    GetCursorPos(P);
+    P := AControl.ScreenToClient(P);
+    CallDefaultWindowProc(TWinControl(AControl).Handle, WM_LBUTTONUP, 0, MAKELPARAM(P.X, P.Y));
+  end;
+end;
+
 class function TWin32WSCustomListBox.GetIndexAtXY(
   const ACustomListBox: TCustomListBox; X, Y: integer): integer;
 begin
@@ -655,7 +672,9 @@ begin
     Result := SendMessage(ACustomListBox.Handle, LB_GETCURSEL, 0, 0);
 end;
 
-class function TWin32WSCustomListBox.GetItemRect(const ACustomListBox: TCustomListBox; Index: integer; var ARect: TRect): Boolean;
+class function TWin32WSCustomListBox.GetItemRect(
+  const ACustomListBox: TCustomListBox; Index: integer; var ARect: TRect
+  ): boolean;
 var
   Handle: HWND;
 begin

lcl/widgetset/wscontrols.pp

@@ -84,6 +84,7 @@ type
     class function GetDefaultColor(const AControl: TControl; const ADefaultColorType: TDefaultColorType): TColor; virtual;
     class procedure ConstraintWidth(const AControl: TControl; const AConstraints: TObject; var aWidth: integer); virtual;
     class procedure ConstraintHeight(const AControl: TControl; const AConstraints: TObject; var aHeight: integer); virtual;
+    class procedure DragStart(const AControl: TControl; const Immediate: Boolean); virtual;
   end;
 
   TWSControlClass = class of TWSControl;
@@ -229,6 +230,10 @@ begin
 
 end;
 
+class procedure TWSControl.DragStart(const AControl: TControl; const Immediate: Boolean);
+begin
+end;
+
 { TWSWinControl }
 
 class procedure TWSWinControl.AdaptBounds(const AWinControl: TWinControl;