Thema: Delphi Alt -> Stacküberlauf

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blablab

Registriert seit: 3. Jan 2006
509 Beiträge
 
Delphi 7 Enterprise
 
#6

AW: Alt -> Stacküberlauf

  Alt 1. Jul 2010, 13:34
Er ruft sich hier immer wieder (indirekt) selbst auf, bei jedem aufruf speichert er sich ein paar lokale Variablen im Stack und irgendwann ist der Stack voll...

Delphi-Quellcode:
procedure TWinControl.WMSysCommand(var Message: TWMSysCommand);
var
  Form: TCustomForm;

  function TraverseControls(Container: TWinControl): Boolean;
  var
    I: Integer;
    Control: TControl;
  begin
{3} Result := False;
    if Container.Showing then
      for I := 0 to Container.ControlCount - 1 do
      begin
        Control := Container.Controls[I];
        if Control.Visible and Control.Enabled then
        begin
          if (csMenuEvents in Control.ControlStyle) and
{4}         (Control.Perform(WM_SYSCOMMAND, TMessage(Message).WParam,
              TMessage(Message).LParam) <> 0) or (Control is TWinControl) and
            TraverseControls(TWinControl(Control)) then
          begin
            Result := True;
            Exit;
          end;
        end;
      end;
  end;

begin
  with Message do
  begin
{1}{5}if (CmdType and $FFF0 = SC_KEYMENU) and (Key <> VK_SPACE) and
      (Key <> Word('-')) and not IsIconic(FHandle) and (GetCapture = 0) and
      (Application.MainForm <> Self) then
    begin
      Form := GetParentForm(Self);
      if (Form <> nil) and
{6}     (Form.Perform(CM_APPSYSCOMMAND, 0, Longint(@Message)) <> 0) then
        Exit;
    end;
    { Broadcast WMSysCommand to all controls which have a csMenuEvents style. }
{2} if (CmdType and $FFF0 = SC_KEYMENU) and TraverseControls(Self) then
      Exit;
  end;
  inherited;
end;

procedure TCustomForm.CMAppSysCommand(var Message: TMessage);
type
  PWMSysCommand = ^TWMSysCommand;
begin
  Message.Result := 0;
  if (csDesigning in ComponentState) or (FormStyle = fsMDIChild) or
   (Menu = nil) or Menu.AutoMerge then
    with PWMSysCommand(Message.lParam)^ do
    begin
      SendCancelMode(nil);
{7}   if SendAppMessage(CM_APPSYSCOMMAND, CmdType, Key) <> 0 then
        Message.Result := 1;;
    end;
end;

procedure TApplication.WndProc(var Message: TMessage);
...
begin
...
    with Message do
      case Msg of
...
        CM_APPSYSCOMMAND:
          if MainForm <> nil then
            with MainForm do
              if (Handle <> 0) and IsWindowEnabled(Handle) and
                IsWindowVisible(Handle) then
              begin
                FocusMessages := False;
                SaveFocus := GetFocus;
                Windows.SetFocus(Handle);
{8}             Perform(WM_SYSCOMMAND, WParam, LParam);
                Windows.SetFocus(SaveFocus);
                FocusMessages := True;
                Result := 1;
              end;
...
end;
Es geht immer {1}...{8}{1}...{8}{1}...

Jetzt muss ich nurnoch verstehen was er da macht und was ich falsch gemacht habe...

Geändert von blablab ( 1. Jul 2010 um 13:47 Uhr)
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