In the system menu (topleft of titlebar), I can add my own menu items.
I can also delete e.g.DeleteMenu(SysMenu, SC_MINIMIZE, MF_BYCOMMAND) ;
However if I delete the standard ones [restore,minimize,maximize,size,close] their functionality is lost (i.e. maximize button no longer works)
Is there a way to hide these menuitems or move them off the first rank of the system menu? a) make them not visible b) move to a submenu c) delete but still get button messages
a) make them not visible
The API has no concept of a hidden/invisible menu item.
b) move to a submenu
You can move (or rather delete and add) items to a submenu without effecting functionality.
E.g. move "minimize" to a submenu:
var
SysMenu, SubMenu: HMENU;
StrMin: string;
StrMinLen: Integer;
begin
SysMenu := GetSystemMenu(Handle, False);
StrMinLen := GetMenuString(SysMenu, SC_MINIMIZE, nil, 0, MF_BYCOMMAND);
if StrMinLen > 0 then begin
Inc(StrMinLen);
SetLength(StrMin, StrMinLen);
GetMenuString(SysMenu, SC_MINIMIZE, PChar(StrMin), StrMinLen, MF_BYCOMMAND);
SubMenu := CreateMenu;
if SubMenu <> 0 then begin
DeleteMenu(SysMenu, SC_MINIMIZE, MF_BYCOMMAND);
AppendMenu(SubMenu, MF_STRING, SC_MINIMIZE, PChar(StrMin));
InsertMenu(SysMenu, 0, MF_BYPOSITION or MF_POPUP, SubMenu, 'Minimize->');
InsertMenu(SysMenu, 1, MF_BYPOSITION or MF_SEPARATOR, 0, nil);
end;
end;
Destroy the submenu before restoring the system menu:
var
Info: TMenuItemInfo;
begin
Info.cbSize := SizeOf(Info);
Info.fMask := MIIM_SUBMENU;
if GetMenuItemInfo(GetSystemMenu(Handle, False), 0, True, Info) then
DestroyMenu(Info.hSubMenu);
GetSystemMenu(Handle, True);
c) delete but still get button messages
If you delete, f.i., the "minimize" item, the system does not send WM_SYSCOMMAND messages for the minimize command to the window. So there won't be any command to respond to.
You can still listen for button messages, f.i. a left button down. But a button down/up message is not actually the same thing with a button click. A button click consists of three actions, mouse down, capture and up again on the button. If you want to do it anyway an example can be:
procedure TForm1.WMNCLButtonDown(var Message: TWMNCLButtonDown);
begin
inherited;
if (Message.HitTest = HTMINBUTTON) and not IsIconic(Handle) then
ShowWindow(Handle, SW_MINIMIZE);
end;
Originally, the window caption had only two buttons in the upper right corner, the minimize and maximize buttons, and they were controlled with a window style. Windows 95 added the Close button, but then there was the question of knowing when to enable and disable it. But wait, we already know when to enable and disable it: The application told us when it enabled and disabled the SC_CLOSE menu item. Bingo, just hook up the Close button to the existing menu item (which applications were already in the habit of maintaining), and magic, it just works. No need for applications to write special code to support the Close button.
Now you know why SC_CLOSE is tied to the button. The correct way prevent the user from closing during some operation is therefore to disable the menu item.
If you insist on deleting it for whatever reason but still allowing the window to be closed then you have to delete the item when the system menu is about to be displayed (WM_INITMENU) and revert the system menu after the menu is closed (WM_UNINITMENUPOPUP).
Sertac has answered the question: You can only move them.
Here is the complete final solution to making the Sysmenu useful, which does: a) Moves all standard items except close to a submenu, which is hidden behind a separator. b) Adds menu items from Form1.PopupMenu1 to the SysMenu c) removes them (before making the window fullscreen/borderless as this destroys the sysmenu) d) shows the sysmenu
procedure TForm1.SysMenuAddRemoveExtraItems(Add:boolean=true);
//
var
SysMenu, SubMenu : HMenu;
const NumItems:integer=0;
procedure InsertM(Position,I:integer;J:integer=-1;S:string='');
// https://msdn.microsoft.com/en-us/library/windows/desktop/ms647987(v=vs.85).aspx
var M:TMenuItem; H:thandle; Flags:cardinal;
begin
M:=PopupMenu1.Items;
if I>=0 then M:=M.Items[I];
Flags:=MF_BYPOSITION+MF_STRING;
if M.Count>1 then Flags:=Flags+MF_POPUP;
if J>=0 then M:=M.Items[J];
H:=M.Handle;
if S='' then S:=M.Caption;
InsertMenu(SysMenu,Position,Flags,H,pwidechar(S));
inc(NumItems);
end;
procedure InsertSeparator(Position:integer);
begin
InsertMenu(SysMenu,Position,MF_BYPOSITION,MF_SEPARATOR,0); {Add a seperator bar to main form-form1}
inc(NumItems);
end;
procedure RemoveItems;
var i:integer;
begin
for i := 1 to NumItems do //remove items from top
RemoveMenu(SysMenu,0,MF_BYPOSITION);
NumItems:=0;
end;
procedure DeleteAppend(ID:cardinal); //to move standard menuitems to submenu
var
Caption: string;
CaptionLen: Integer;
begin
CaptionLen := GetMenuString(SysMenu, ID, nil, 0, MF_BYCOMMAND);
if CaptionLen > 0 then begin
Inc(CaptionLen);
SetLength(Caption, CaptionLen);
GetMenuString(SysMenu, ID, PChar(Caption), CaptionLen, MF_BYCOMMAND);
DeleteMenu(SysMenu, ID, MF_BYCOMMAND);
AppendMenu(SubMenu, MF_STRING, ID, PChar(Caption));
end;
end;
procedure MoveDefaultSysMenuItemsToSubmenu(Caption:string='';JustSeparator:boolean=false);
//Can either have a a caption or JustSeparator (submenu will be inaccessible)
// https://stackoverflow.com/questions/44735708/system-menu-how-to-hide-move-standard-menuitems/44743027#44743027
begin
SubMenu := CreateMenu; //make submenu to move them into
if SubMenu <> 0 then begin
DeleteAppend(SC_RESTORE);
DeleteAppend(SC_MOVE);
DeleteAppend(SC_SIZE);
DeleteAppend(SC_MINIMIZE);
DeleteAppend(SC_MAXIMIZE);
if JustSeparator then begin
DeleteMenu(SysMenu, 0, MF_BYPOSITION); //remove separator above CLOSE
InsertMenu(SysMenu, 0, MF_BYPOSITION or MF_POPUP or MF_SEPARATOR, SubMenu, '');
end else begin
DeleteMenu(SysMenu, 0, MF_BYPOSITION); //remove separator above CLOSE
InsertMenu(SysMenu, 0, MF_BYPOSITION or MF_POPUP, SubMenu, PChar(Caption));
InsertMenu(SysMenu, 1, MF_BYPOSITION or MF_SEPARATOR, 0, nil);
end;
end;
end;
procedure DestroySubmenu;
var Info: TMenuItemInfo;
begin
Info.cbSize := SizeOf(Info);
Info.fMask := MIIM_SUBMENU;
if GetMenuItemInfo(GetSystemMenu(Handle, False), 0, True, Info) then
DestroyMenu(Info.hSubMenu);
//GetSystemMenu(Handle, True);
end;
begin
SysMenu := GetSystemMenu(Handle, FALSE) ; {Get system menu}
//InsertMenu(SysMenu,1,MF_BYPOSITION+MF_STRING,SC_MyMenuItem2,'pqr');
if Add then begin
MoveDefaultSysMenuItemsToSubmenu('',true);
// InsertSeparator(0);
InsertM(0,PopupMenu1.Items.Count-2);
InsertM(0,-1,-1,'Menu'); //help
InsertM(0,7);
end
else begin //remove items
RemoveItems;
DestroySubmenu;
end;
end;
//------------------------------------
procedure TForm1.ShowSysMenu;
var P:TPoint;
begin
P:=ClientToScreen(Point(0,0));
TrackPopupMenu(GetSystemMenu(Handle, FALSE), TPM_LEFTALIGN+TPM_TOPALIGN+TPM_RETURNCMD+TPM_NONOTIFY,
P.X,P.Y,0,self.Handle,nil);
end;
//--------------------------------------------------------------
procedure TForm1.WMSysCommand(var Msg: TWMSysCommand);
// https://www.delphipower.xyz/guide_7/customizing_the_system_menu.html
var Item: TMenuItem;
begin
Item := PopupMenu1.FindItem (Msg.CmdType, fkCommand);
if assigned(Item) then Item.Click
else
// case Msg.CmdType of
// //put any other specials in here
// else
inherited;
// end;
end;