网站 › 『编程语言讨论求助区』 › 求教，以下代码为啥挂起了？

冥界3大法王 发表于 2020-10-5 23:03

求教，以下代码为啥挂起了？

unit Unit1;

interface

uses
Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants,
System.Classes, Vcl.Graphics, Vcl.Controls, Vcl.Forms, Vcl.Dialogs;

type
TForm1 = class(TForm)
    procedure FormCreate(Sender: TObject);
private
    procedure sysmenu(var msg: twmmenuselect); message wm_syscommand;
    { Private declarations }
public
    { Public declarations }
end;

var
Form1: TForm1;

implementation

{$R *.dfm}

procedure TForm1.FormCreate(Sender: TObject);
var
i: integer;
begin
i := getsystemmenu(handle, false);
appendmenu(i, mf_separator, 0, nil);
appendmenu(i, mf_string, 100, '窗口置顶');
end;

procedure TForm1.sysmenu(var msg: twmmenuselect);
begin
if msg.IDItem = 100 then
    SetWindowPos(Form1.Handle, HWND_TOPMOST, 0, 0, 0, 0, SWP_NOMOVE or SWP_NOSIZE)
else
    SetWindowPos(Form1.Handle, HWND_NOTOPMOST, 0, 0, 0, 0, SWP_NOMOVE or SWP_NOSIZE);
end;

end.

bookaccount 发表于 2020-10-6 00:24

参考 https://stackoverflow.com/questions/38119347/why-is-a-window-not-coming-to-top-inspite-using-setwindowpos

冥界3大法王 发表于 2020-10-6 08:50

明白了，
procedure TForm1.sysmenu(var msg: TWMMenuSelect);
begin
if msg.IDItem = 100 then
    SetWindowPos(Form1.Handle, HWND_TOPMOST, 0, 0, 0, 0, SWP_NOMOVE or SWP_NOSIZE)
else
    inherited;


if msg.IDItem = 101 then
    SetWindowPos(Form1.Handle, HWND_NOTOPMOST, 0, 0, 0, 0, SWP_NOMOVE or SWP_NOSIZE)
else
    inherited;
end;

查看完整版本: 求教，以下代码为啥挂起了？