ProgressDialog（その4）

長くなってしまったのエントリを変えた。まえのエントリではDestroyをちょっと追った。
こんどはProgressDialogを実装しているsrc/generic/progdlgg.cpp

まずは::Updateの中でbarがいっぱいになるようなvalueを渡したときの処理が行われる部分。

    if ( value == m_maximum )
    {
        if ( m_state == Finished )
        {
            // ignore multiple calls to Update(m_maximum): it may sometimes be
            // troublesome to ensure that Update() is not called twice with the
            // same value (e.g. because of the rounding errors) and if we don't
            // return now we're going to generate asserts below
            return true;
        }

        // so that we return true below and that out [Cancel] handler knew what
        // to do
        m_state = Finished;
        if( !(GetWindowStyle() & wxPD_AUTO_HIDE) )
        {
            EnableClose();
            DisableSkip();
#if defined(__WXMSW__) && !defined(__WXUNIVERSAL__)
            EnableCloseButton();
#endif // __WXMSW__

            if ( newmsg.empty() )
            {
                // also provide the finishing message if the application didn't
                m_msg->SetLabel(_("Done."));
            }

            wxYieldIfNeeded() ;

            (void)ShowModal();
        }
        else // auto hide
        {
            // reenable other windows before hiding this one because otherwise
            // Windows wouldn't give the focus back to the window which had
            // been previously focused because it would still be disabled
            ReenableOtherWindows();

            Hide();
        }
    }
    else // not at maximum yet    if ( value == m_maximum )

デストラクタとReenableOtherWindows

// ----------------------------------------------------------------------------
// destruction
// ----------------------------------------------------------------------------

wxProgressDialog::~wxProgressDialog()
{
    // normally this should have been already done, but just in case
    ReenableOtherWindows();
}

void wxProgressDialog::ReenableOtherWindows()
{
    if ( GetWindowStyle() & wxPD_APP_MODAL )
    {
        delete m_winDisabler;
        m_winDisabler = (wxWindowDisabler *)NULL;
    }
    else
    {
        if ( m_parentTop )
            m_parentTop->Enable();
    }
}

でいくつか気になるメンバ変数があるが、m_parentTopはコンストラクタの中で

m_parentTop = wxGetTopLevelParent(parent);

となっている。

wxGetTopLevelParentの実装は、src/common/wincmn.cpp

// ----------------------------------------------------------------------------
// global functions
// ----------------------------------------------------------------------------

wxWindow* wxGetTopLevelParent(wxWindow *win)
{
    while ( win && !win->IsTopLevel() )
         win = win->GetParent();

    return win;
}

関連は不明だがなにかあるのかもしれない。一応よんでみた。

::wxGetTopLevelParent() returns NULL @ wx-users
要点：wxTopLevelWindowはDestroyの過程でwxWindowに成り下がった後、自分の子をDestroyし、最後になくなる。なので、Destroyされる子の側でよぶとNULL返すことになる

Why does wxGetTopLevelParent() not return a wxTopLevelWindow?

wxWindowDisablerも気になる。実装はsrc/common/utilscmn.cppにある。
概要としてはwxTopLevelWindows.GetFirstでTopWindowのリストにあるwindowにたいしてdisableを呼んでいる。

// ----------------------------------------------------------------------------
// wxSafeYield and supporting functions
// ----------------------------------------------------------------------------

void wxEnableTopLevelWindows(bool enable)
{
    wxWindowList::compatibility_iterator node;
    for ( node = wxTopLevelWindows.GetFirst(); node; node = node->GetNext() )
        node->GetData()->Enable(enable);
}

wxWindowDisabler::wxWindowDisabler(wxWindow *winToSkip)
{
    // remember the top level windows which were already disabled, so that we
    // don't reenable them later
    m_winDisabled = NULL;

    wxWindowList::compatibility_iterator node;
    for ( node = wxTopLevelWindows.GetFirst(); node; node = node->GetNext() )
    {
        wxWindow *winTop = node->GetData();
        if ( winTop == winToSkip )
            continue;

        // we don't need to disable the hidden or already disabled windows
        if ( winTop->IsEnabled() && winTop->IsShown() )
        {
            winTop->Disable();
        }
        else
        {
            if ( !m_winDisabled )
            {
                m_winDisabled = new wxWindowList;
            }

            m_winDisabled->Append(winTop);
        }
    }
}

wxWindowDisabler::~wxWindowDisabler()
{
    wxWindowList::compatibility_iterator node;
    for ( node = wxTopLevelWindows.GetFirst(); node; node = node->GetNext() )
    {
        wxWindow *winTop = node->GetData();
        if ( !m_winDisabled || !m_winDisabled->Find(winTop) )
        {
            winTop->Enable();
        }
        //else: had been already disabled, don't reenable
    }

    delete m_winDisabled;
}