源代码放送，解决MDI的DLL子窗体中的tab健下移控件问题

Question

一般在dll中，MDI子窗体中的tab是无效的，可以通过注册热健解决
经常看到有人提MDIdll的问题，现在我把
源代码贴出来如下
//这是主窗体的代码
unit callsdifrm;interfaceuses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, StdCtrls, ExtCtrls, ComCtrls, Menus;type
  TForm1 = class(TForm)
    MainMenu1: TMainMenu;
    ShowSdi1: TMenuItem;
    ShowSdi2: TMenuItem;
    CloseSdi1: TMenuItem;
    adsfsdf1: TMenuItem;
    N121: TMenuItem;
    procedure CloseSdi1Click(Sender: TObject);
    procedure FormCloseQuery(Sender: TObject; var CanClose: Boolean);
    procedure FormClose(Sender: TObject; var Action: TCloseAction);
    procedure ShowSdi2Click(Sender: TObject);
    procedure adsfsdf1Click(Sender: TObject);
  private
    { Private declarations }
    //声明响应WM_HOTKEY消息的方法
    procedure WMHotKey(var Msg: TWMHotKey); message WM_HOTKEY;
    function GetSysFocus: Integer;
  public
    { Public declarations }
    procedure WMACTIVATEAPP(var Msg: TMessage); message WM_ACTIVATEAPP;
  end;var
  Form1: TForm1;
  Procedure ShowFrm(ParentApplication: TApplication);stdcall;external 'demodll.dll';
  Procedure CloseFrm;stdcall;external 'demodll.dll';
  procedure freeDll; stdcall;external 'demodll.dll';
implementation
const id_SnapShot = 115; //定义热键标识符
{$R *.dfm}procedure TForm1.CloseSdi1Click(Sender: TObject);
begin
  CloseFrm;
end;procedure TForm1.FormCloseQuery(Sender: TObject; var CanClose: Boolean);
begin
  CloseFrm;
end;procedure TForm1.FormClose(Sender: TObject; var Action: TCloseAction);
begin
  freeDll;
end;procedure TForm1.ShowSdi2Click(Sender: TObject);
begin
  ShowFrm(Application);
end;procedure TForm1.adsfsdf1Click(Sender: TObject);
begin
  Close;
end;procedure TForm1.WMHotKey(var Msg: TWMHotKey);
var
  H: THandle;
begin
  if Msg.HotKey = id_SnapShot then
  begin
    H := GetSysFocus;
    while IsWindow(H) and (H <> Form1.Handle) do
    begin
      SendMessage(H,WM_NEXTDLGCTL,0,0);
      H := GetParent(H);
    end;
  end;
end;function TForm1.GetSysFocus: Integer;
var
  hOtherWin,OtherThreadID,hFocusWin:integer;
begin
  hOtherWin:=GetForegroundWindow;
  OtherThreadID:=GetWindowThreadProcessID(hOtherWin,nil);
  if AttachThreadInput(GetcurrentThreadID,OtherThreadID,True) then
  begin
    hFocusWin:=GetFocus;
    result:=GetFocus;
  if HFocusWin<>0 then
  try
  //SendMessage(GetFocus,WM_COPY,0,0);//书上是这么写的
  finally
    AttachThreadInput(GetcurrentThreadID,OtherThreadID,False);
  end;
  end
  else result:=GetFocus;
end;procedure TForm1.WMACTIVATEAPP(var Msg: TMessage);
begin
  if Boolean(Msg.WParam) then
    RegisterHotKey(Form1.Handle, id_SnapShot, 0, VK_TAB) //定义热键  在程序得到焦点时
  else
    UnRegisterHotKey(Form1.Handle, id_SnapShot); //释放已经登记的热键 在程序失去焦点时
end;end.以上是MDI主窗体代码下面是子窗体dll中的代码
library demodll;
uses
  SysUtils,
  Classes,
  Forms,
  Windows,
  sdifrm in 'sdifrm.pas' {frmsdi};{$R *.res}exports
  ShowFrm,CloseFrm,freeDll;begin
  DllApplication := Application;  //一定要将主窗体的Appliction传入，释放时候赋值回去
end.

Answer 1

下面这是MDI子窗体的代码unit sdifrm;interfaceuses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, StdCtrls, ExtCtrls;  Procedure ShowFrm(ParentApplication: TApplication);stdcall;
  Procedure CloseFrm;stdcall;
  procedure freeDll; stdcall;var
  DllApplication: TApplication;
type
  Tfrmsdi = class(TForm)
    pnlUIfrm: TPanel;
    Panel2: TPanel;
    Button1: TButton;
    Edit1: TEdit;
    Edit2: TEdit;
    Edit3: TEdit;
    Edit4: TEdit;
    Edit5: TEdit;
    Edit6: TEdit;
    procedure FormClose(Sender: TObject; var Action: TCloseAction);
  private
    { Private declarations }
  public
    { Public declarations }
  end;var
  frmsdi: Tfrmsdi;
implementation
{$R *.dfm}
procedure freeDll;stdcall;
begin
  Application := DllApplication;
end;Procedure ShowFrm(ParentApplication: TApplication);stdcall;
begin
  Application := ParentApplication;
  if Not Assigned(frmsdi) then
  begin
    frmsdi := Tfrmsdi.Create(Application);
    frmsdi.Show;
  end;
end;Procedure CloseFrm;stdcall;
begin
  if Assigned(frmsdi) then
  begin
    FreeAndNil(frmsdi);
  end
  else
    frmsdi := nil;
end;procedure Tfrmsdi.FormClose(Sender: TObject; var Action: TCloseAction);
begin
  Action := caFree;
  frmsdi := Nil;
end;end.

Answer 2

当然上次看到一个贴子需要屏蔽拷屏健的功能，也能通过注册热健解决
把上面例子中的VK_TAB换成VK_SNAPSHOT就行了，不做任何操作的话就可以屏蔽掉，当然你也可以替换掉

Answer 3

当然要替换按健，也是在
procedure TForm1.WMHotKey(var Msg: TWMHotKey);
var
  H: THandle;
begin
  if Msg.HotKey = id_SnapShot then
    KeyBD_event(Byte(VK_Return),0,0,0);  //就可以把它换成回车了
end;function TForm1.GetSysFocus: Integer;
var
  hOtherWin,OtherThreadID,hFocusWin:integer;
begin
  hOtherWin:=GetForegroundWindow;
  OtherThreadID:=GetWindowThreadProcessID(hOtherWin,nil);
  if AttachThreadInput(GetcurrentThreadID,OtherThreadID,True) then
  begin
    hFocusWin:=GetFocus;
    result:=GetFocus;
  if HFocusWin<>0 then
  try
  //SendMessage(GetFocus,WM_COPY,0,0);//书上是这么写的
  finally
    AttachThreadInput(GetcurrentThreadID,OtherThreadID,False);
  end;
  end
  else result:=GetFocus;
end; //这段代码是得到当前正在输入控件的Handle