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POCan overriding the CreateParams procedure allow me to still have full access to the WS_SYSMENU?
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copied!<p>Complete source code can be found here: <a href="http://www.eyeClaxton.com/download/delphi/SkinProject.zip" rel="nofollow">http://www.eyeClaxton.com/download/delphi/SkinProject.zip</a></p> <p>I'm trying to create a skinned form with no "Caption or Borders", but still leaving me with the full access to System Menu (I.E: Move, Minimize, Maximize, Restore and Size). I can achieve all of the menu items by overriding the CreateParams procedure by using WS_SYSMENU, WS_MAXIMIZEBOX, WS_MINIMIZEBOX. Using the WS_SIZEBOX gives me access to the menu "Size" command but paints a border I do not want. I have included a complete (Delphi 7) example in the link above. If more information is needed, please feel free to ask.</p> <pre><code>procedure TMainFrm.CreateParams(var Params: TCreateParams); begin FormStyle := fsNormal; try if (BorderIcons <> []) then BorderIcons := []; if (BorderStyle <> bsNone) then BorderStyle := bsNone; inherited CreateParams(Params); Params.ExStyle := (Params.ExStyle and (not WS_EX_WINDOWEDGE) and (not WS_EX_STATICEDGE) and (not WS_EX_DLGMODALFRAME) and (not WS_EX_CLIENTEDGE)); Params.Style := (Params.Style and (not WS_CAPTION) and (not DS_MODALFRAME) and (not WS_DLGFRAME) and (not WS_THICKFRAME)); Params.Style := (Params.Style or WS_SYSMENU or WS_MAXIMIZEBOX or WS_MINIMIZEBOX or WS_SIZEBOX); finally Position := poScreenCenter; end; end; </code></pre> <p>SOLUTION:</p> <pre><code>unit WndProcUnit; interface uses Windows, Messages, Classes, Controls, Forms, SysUtils; type EWndProc = class(Exception); TWndProcMessages = class(TComponent) private { Private declarations } FOwnerWndProc: TFarProc; FNewWndProc: TFarProc; protected { Protected declarations } procedure WndProc(var theMessage: TMessage); virtual; public { Public declarations } constructor Create(theOwner: TComponent); override; destructor Destroy(); override; procedure DefaultHandler(var theMessage); override; end; TWndProc = class(TWndProcMessages) private { Private declarations } protected { Protected declarations } procedure Loaded(); override; public { Public declarations } constructor Create(theOwner: TComponent); override; destructor Destroy(); override; published { Published declarations } end; implementation { TWndProcMessages } constructor TWndProcMessages.Create(theOwner: TComponent); var X, I: Integer; begin inherited Create(theOwner); if (not (Owner is TForm)) then raise EWndProc.Create('TWndProc parent must be a form!'); I := 0; for X := 0 to (Owner.ComponentCount - 1) do begin if (Owner.Components[X] is TWndProc) then Inc(I); if (I > 1) then Break; end; if (I > 1) then begin raise EWndProc.Create('The form already contains a TWndProc!'); end else begin FOwnerWndProc := TFarProc(GetWindowLong((Owner as TForm).Handle, GWL_WNDPROC)); FNewWndProc := Classes.MakeObjectInstance(WndProc); if (not (csDesigning in ComponentState)) then SetWindowLong((Owner as TForm).Handle, GWL_WNDPROC, LongInt(FNewWndProc)); end; end; destructor TWndProcMessages.Destroy(); begin if Assigned(FNewWndProc) then try Classes.FreeObjectInstance(FNewWndProc); finally if (Pointer(FNewWndProc) <> nil) then Pointer(FNewWndProc) := nil; end; if Assigned(FOwnerWndProc) then Pointer(FOwnerWndProc) := nil; inherited Destroy(); end; procedure TWndProcMessages.DefaultHandler(var theMessage); begin if ((Owner as TForm).Handle <> 0) then begin case TMessage(theMessage).Msg of WM_DESTROY: SetWindowLong((Owner as TForm).Handle, GWL_WNDPROC, LongInt(FOwnerWndProc)); WM_INITMENU: EnableMenuItem(TMessage(theMessage).WParam, SC_SIZE, MF_BYCOMMAND or MF_ENABLED); else with TMessage(theMessage) do Result := CallWindowProc(FOwnerWndProc, (Owner as TForm).Handle, Msg, WParam, LParam); end; end else inherited DefaultHandler(theMessage); end; procedure TWndProcMessages.WndProc(var theMessage: TMessage); begin Dispatch(theMessage); end; { TWndProc } constructor TWndProc.Create(theOwner: TComponent); begin inherited Create(theOwner); end; destructor TWndProc.Destroy(); begin inherited Destroy(); end; procedure TWndProc.Loaded(); begin inherited Loaded(); if (not (csDesigning in ComponentState)) then GetSystemMenu((Owner as TForm).Handle, False); end; end. </code></pre> <p>Complete "updated" source code can be found here: <a href="http://www.eyeClaxton.com/download/delphi/SkinProject.zip" rel="nofollow">http://www.eyeClaxton.com/download/delphi/SkinProject.zip</a></p>

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