ShowModa窗体l如何一定要显示在前面

[zuilu5339]

application.CreateForm(TFrm_editBom,Frm_editBom);
Frm_editBom.ShowModal;
Frm_editBom.Free;
正常来说都是显示在最前面，有时候我感觉是有点卡就显示不在最前面，然后只能退出，重来

[BlueStorm]

//这样不是更好吗：
with TFrm_editBom.Create(nil) do
begin
  ShowModal;
  Free;
end;

[zuilu5339]

引用 1 楼 BlueStorm 的回复:

//这样不是更好吗：
with TFrm_editBom.Create(nil) do
begin
  ShowModal;
  Free;
end;

好是好，但好像没解决问题，只是代码省略了

[日立奔腾浪潮微软松下联想]

不先AttachThreadInput在win10上调用SetForegroundWindow会失败

[zuilu5339]

引用 6 楼 BlueStorm 的回复:

示例
unit Unit4;

interface

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

const
  WM_AFTER_SHOW = WM_USER + 1;

type
  TFrm_editBom = class(TForm)
    procedure FormShow(Sender: TObject);
  private
    procedure WmAfterShow (var Msg: TMessage); message WM_AFTER_SHOW;
  public
    { Public declarations }
  end;

var
  Frm_editBom: TFrm_editBom;

function ForceForegroundWindow(hWnd: THandle): Boolean;

implementation

{$R *.dfm}

procedure TFrm_editBom.FormShow(Sender: TObject);
begin
  PostMessage(Handle, WM_AFTER_SHOW, 0, 0);
end;

procedure TFrm_editBom.WmAfterShow(var Msg: TMessage);
begin
  Application.ProcessMessages;
  ForceForegroundWindow(Handle);
end;

function ForceForegroundWindow(hWnd: THandle): Boolean;
var
  HelpForm: TForm;
begin
  HelpForm := TForm.Create(nil);
  try
    HelpForm.BorderStyle := bsNone;
    HelpForm.SetBounds(0, 0, 1, 1);
    HelpForm.FormStyle := fsStayOnTop;
    HelpForm.Show;
    mouse_event(MOUSEEVENTF_ABSOLUTE or MOUSEEVENTF_LEFTDOWN, 0, 0, 0, 0);
    mouse_event(MOUSEEVENTF_ABSOLUTE or MOUSEEVENTF_LEFTUP, 0, 0, 0, 0);
    SetForegroundWindow(hWnd);
  finally
    HelpForm.Free;
  end;
  Result := True;
end;

end.

你的太复杂了
而且我是ShowModal， 不是show，光加fsStayOnTop;好像没用

[BlueStorm]

我试过了，是可以的。

最好用第一个function ForceForegroundWindow(hWnd: THandle): Boolean; 第二个ForceForegroundWindow不太完善。
代码是加在被showModal出来的form里面，因此show和ShowModal都工作正常。

你觉得太复杂，那我就没办法了，我找不到其他可靠又更简单的方法。

[zuilu5339]

还有没有办法

[BlueStorm]

function ForceForegroundWindow(hWnd: THandle): Boolean;
const
SPI_GETFOREGROUNDLOCKTIMEOUT = $2000;
SPI_SETFOREGROUNDLOCKTIMEOUT = $2001;
var
ForegroundThreadID: DWORD;
ThisThreadID: DWORD;
timeout: DWORD;
begin
if GetForegroundWindow = hWnd then
Result := True
else
begin
Result := False;
ForegroundThreadID := GetWindowThreadProcessID(GetForegroundWindow, nil);
ThisThreadID := GetWindowThreadPRocessId(hWnd, nil);
if AttachThreadInput(ThisThreadID, ForegroundThreadID, True) then
begin
BringWindowToTop(hWnd);
SetForegroundWindow(hWnd);
AttachThreadInput(ThisThreadID, ForegroundThreadID, False);
Result := (GetForegroundWindow = hWnd);
end;
if not Result then
begin
SystemParametersInfo(SPI_GETFOREGROUNDLOCKTIMEOUT, 0, @timeout, 0);
SystemParametersInfo(SPI_SETFOREGROUNDLOCKTIMEOUT, 0, TObject(0),
SPIF_SENDCHANGE);
BringWindowToTop(hWnd);
SetForegroundWindow(hWnd);
SystemParametersInfo(SPI_SETFOREGROUNDLOCKTIMEOUT, 0, TObject(timeout), SPIF_SENDCHANGE);
end;
Result := (GetForegroundWindow = hWnd);
end;
end;

[BlueStorm]

或者：
function ForceForegroundWindow(hWnd: THandle): Boolean;
var
  HelpForm: TForm;
begin
  HelpForm := TForm.Create(nil);
  try
    HelpForm.BorderStyle := bsNone;
    HelpForm.SetBounds(0, 0, 1, 1);
    HelpForm.FormStyle := fsStayOnTop;
    HelpForm.Show;
    mouse_event(MOUSEEVENTF_ABSOLUTE or MOUSEEVENTF_LEFTDOWN, 0, 0, 0, 0);
    mouse_event(MOUSEEVENTF_ABSOLUTE or MOUSEEVENTF_LEFTUP, 0, 0, 0, 0);
    SetForegroundWindow(hWnd);
  finally
    HelpForm.Free;
  end;
  Result := True;
end;

[BlueStorm]

示例
unit Unit4;

interface

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

const
  WM_AFTER_SHOW = WM_USER + 1;

type
  TFrm_editBom = class(TForm)
    procedure FormShow(Sender: TObject);
  private
    procedure WmAfterShow (var Msg: TMessage); message WM_AFTER_SHOW;
  public
    { Public declarations }
  end;

var
  Frm_editBom: TFrm_editBom;

function ForceForegroundWindow(hWnd: THandle): Boolean;

implementation

{$R *.dfm}

procedure TFrm_editBom.FormShow(Sender: TObject);
begin
  PostMessage(Handle, WM_AFTER_SHOW, 0, 0);
end;

procedure TFrm_editBom.WmAfterShow(var Msg: TMessage);
begin
  Application.ProcessMessages;
  ForceForegroundWindow(Handle);
end;

function ForceForegroundWindow(hWnd: THandle): Boolean;
var
  HelpForm: TForm;
begin
  HelpForm := TForm.Create(nil);
  try
    HelpForm.BorderStyle := bsNone;
    HelpForm.SetBounds(0, 0, 1, 1);
    HelpForm.FormStyle := fsStayOnTop;
    HelpForm.Show;
    mouse_event(MOUSEEVENTF_ABSOLUTE or MOUSEEVENTF_LEFTDOWN, 0, 0, 0, 0);
    mouse_event(MOUSEEVENTF_ABSOLUTE or MOUSEEVENTF_LEFTUP, 0, 0, 0, 0);
    SetForegroundWindow(hWnd);
  finally
    HelpForm.Free;
  end;
  Result := True;
end;

end.

[xiaocongzhi]

用WINAPI： SetForegroundWindow

[BlueStorm]

SetForegroundWindow只是请求windows系统把该form显示最前面而已，windows让不让它显示在最前面，那还得看情况。

[不值一提]

试试formStyle属性设置

[doloopcn]

DELPHI 自带的SHOW或者是SHOWMODE都是不能够在Windows下面确保在最前，想确定窗口一定在Windows下保持最前的，就只能用“BlueStorm"的方法吧