自学教程：C++ GetActiveChild函数代码示例

//---------------------------------------------------------void CSAGA_Frame::On_Frame_Close_All(wxCommandEvent &WXUNUSED(event)){	while( GetActiveChild() != NULL )	{		delete(GetActiveChild());	}}

//---------------------------------------------------------void CSAGA_Frame::On_Frame_Close(wxCommandEvent &WXUNUSED(event)){	if( GetActiveChild() != NULL )	{		GetActiveChild()->Close();	}}

// Make sure the correct toolbars are showing for the active viewvoid csFrame::OnIdle(wxIdleEvent& event){    wxSashLayoutWindow* paletteWin = wxGetApp().GetDiagramPaletteSashWindow();    wxSashLayoutWindow* diagramToolBarWin = wxGetApp().GetDiagramToolBarSashWindow();    if (!paletteWin || !diagramToolBarWin)        return;    bool doLayout = false;    if (GetActiveChild())    {        if (!paletteWin->IsShown() || !diagramToolBarWin->IsShown())        {            paletteWin->Show(true);            diagramToolBarWin->Show(true);            doLayout = true;        }    }    else    {        if (paletteWin->IsShown() || diagramToolBarWin->IsShown())        {            paletteWin->Show(false);            diagramToolBarWin->Show(false);            doLayout = true;        }    }    if (doLayout)    {        wxLayoutAlgorithm layout;        layout.LayoutMDIFrame(this);#if defined(__WXMSW__)        // Need to do something else to get it to refresh properly        // when a client frame is first displayed; moving the client        // window doesn't cause the proper refresh. Just refreshing the        // client doesn't work (presumably because it's clipping the        // children).        // FIXED in wxWidgets, by intercepting wxMDIClientWindow::DoSetSize        // and checking if the position has changed, before redrawing the        // child windows.#if 0        wxMDIChildFrame* childFrame = GetActiveChild();        if (childFrame)        {            HWND hWnd = (HWND) childFrame->GetHWND();            ::RedrawWindow(hWnd, NULL, NULL, RDW_FRAME|RDW_ALLCHILDREN|RDW_INVALIDATE );        }#endif#endif // __WXMSW__    }    event.Skip();}

wxMenuItem *wxMDIParentFrame::FindItemInMenuBar(int menuId) const{    wxMenuItem *item = wxFrame::FindItemInMenuBar(menuId);    if ( !item && GetActiveChild() )    {        item = GetActiveChild()->FindItemInMenuBar(menuId);    }    if ( !item && m_windowMenu )        item = m_windowMenu->FindItem(menuId);    return item;}

void wxMDIParentFrame::DoMenuUpdates(wxMenu* menu){    wxMDIChildFrame *child = GetActiveChild();    if ( child )    {        wxEvtHandler* source = child->GetEventHandler();        wxMenuBar* bar = child->GetMenuBar();        if (menu)        {            menu->UpdateUI(source);        }        else        {            if ( bar != NULL )            {                int nCount = bar->GetMenuCount();                for (int n = 0; n < nCount; n++)                    bar->GetMenu(n)->UpdateUI(source);            }        }    }    else    {        wxFrameBase::DoMenuUpdates(menu);    }}

wxMenuItem *wxMDIParentFrame::FindItemInMenuBar(int menuId) const{    // We must look in the child menu first: if it has an item with the same ID    // as in our own menu bar, the child item should be used to determine    // whether it's currently enabled.    wxMenuItem *item = GetActiveChild()                            ? GetActiveChild()->FindItemInMenuBar(menuId)                            : NULL;    if ( !item )        item = wxFrame::FindItemInMenuBar(menuId);    if ( !item && m_windowMenu )        item = m_windowMenu->FindItem(menuId);    return item;}

void CSAGA_Frame::On_Command_Child_UI(wxUpdateUIEvent &event){	CVIEW_Base	*pChild;	if( (pChild = wxDynamicCast(GetActiveChild(), CVIEW_Base)) != NULL )	{		pChild->On_Command_UI(event);	}}

//---------------------------------------------------------void CSAGA_Frame::On_Command_Child(wxCommandEvent &event){	wxMDIChildFrame	*pChild;	if( (pChild = GetActiveChild()) != NULL )	{		pChild->GetEventHandler()->AddPendingEvent(event);	}}

// Default menu selection behaviour - display a help stringvoid wxMDIParentFrame::OnMenuHighlight(wxMenuEvent& event){    if (GetStatusBar())    {        if (event.GetMenuId() == -1)            SetStatusText("");        else        {            wxMenuBar *menuBar = (wxMenuBar*) NULL;            if (GetActiveChild())                menuBar = GetActiveChild()->GetMenuBar();            else                menuBar = GetMenuBar();            if (menuBar)            {                wxString helpString(menuBar->GetHelpString(event.GetMenuId()));                if (helpString != "")                    SetStatusText(helpString);            }        }    }}

void wxMDIParentFrame::InternalSetMenuBar(){    if ( GetActiveChild() )    {        AddWindowMenu();    }    else // we don't have any MDI children yet    {        // wait until we do to add the window menu but do set the main menu for        // now (this is done by AddWindowMenu() as a side effect)        MDISetMenu(GetClientWindow(), (HMENU)m_hMenu, NULL);    }}

bool wxMDIParentFrame::HandleActivate(int state, bool minimized, WXHWND activate){    bool processed = false;    if ( wxWindow::HandleActivate(state, minimized, activate) )    {        // already processed        processed = true;    }    // If this window is an MDI parent, we must also send an OnActivate message    // to the current child.    if ( GetActiveChild() &&         ((state == WA_ACTIVE) || (state == WA_CLICKACTIVE)) )    {        wxActivateEvent event(wxEVT_ACTIVATE, true, GetActiveChild()->GetId());        event.SetEventObject( GetActiveChild() );        if ( GetActiveChild()->HandleWindowEvent(event) )            processed = true;    }    return processed;}

void wxMDIParentFrame::GtkOnSize( int x, int y, int width, int height ){    wxFrame::GtkOnSize( x, y, width, height );    wxMDIChildFrame *child_frame = GetActiveChild();    if (!child_frame) return;    wxMenuBar *menu_bar = child_frame->m_menuBar;    if (!menu_bar) return;    if (!menu_bar->m_widget) return;    menu_bar->m_x = 0;    menu_bar->m_y = 0;    menu_bar->m_width = m_width;    menu_bar->m_height = wxMENU_HEIGHT;    gtk_pizza_set_size( GTK_PIZZA(m_mainWidget),                          menu_bar->m_widget,                          0, 0, m_width, wxMENU_HEIGHT );}

void wxMDIParentFrame::DoGetClientSize(int* width, int* height) const{    wxFrame::DoGetClientSize(width, height);    if (height)    {        wxMDIChildFrame* active_child_frame = GetActiveChild();        if (active_child_frame)        {            wxMenuBar* menubar = active_child_frame->m_menuBar;            if (menubar && menubar->IsShown())            {                GtkRequisition req;                gtk_widget_size_request(menubar->m_widget, &req);                *height -= req.height;                if (*height < 0) *height = 0;            }        }    }}

void MyFrame::FileSavePicture (wxCommandEvent & WXUNUSED(event) ){#if wxUSE_FILEDLG    MyChild * pChild = (MyChild *)GetActiveChild();    if (pChild == NULL)    {        return;    }    wxFileDialog dialog(this, wxT("Save Picture as"), wxEmptyString, pChild->GetTitle(),        wxT("SVG vector picture files (*.svg)|*.svg"),        wxFD_SAVE|wxFD_OVERWRITE_PROMPT);    if (dialog.ShowModal() == wxID_OK)    {        if (!pChild->OnSave ( dialog.GetPath() ))        {            return;        }    }    return;#endif // wxUSE_FILEDLG}

void CSAGA_Frame::On_Frame_Previous_UI(wxUpdateUIEvent &event){	event.Enable(GetActiveChild() != NULL);}

boolwxGenericMDIParentFrame::WXIsActiveChild(wxGenericMDIChildFrame *child) const{    return static_cast<wxMDIChildFrameBase *>(GetActiveChild()) == child;}

void CSAGA_Frame::On_Frame_ArrangeIcons_UI(wxUpdateUIEvent &event){	event.Enable(GetActiveChild() != NULL);}

void wxMDIParentFrame::OnInternalIdle(){    /* if a an MDI child window has just been inserted       it has to be brought to the top in idle time. we       simply set the last notebook page active as new       pages can only be appended at the end */    if (m_justInserted)    {        GtkNotebook *notebook = GTK_NOTEBOOK(m_clientWindow->m_widget);        gtk_notebook_set_page( notebook, g_list_length( notebook->children ) - 1 );        /* need to set the menubar of the child */        wxMDIChildFrame *active_child_frame = GetActiveChild();        if (active_child_frame != NULL)        {            wxMenuBar *menu_bar = active_child_frame->m_menuBar;            if (menu_bar)            {                menu_bar->m_width = m_width;                menu_bar->m_height = wxMENU_HEIGHT;                gtk_pizza_set_size( GTK_PIZZA(m_mainWidget),                                    menu_bar->m_widget,                                    0, 0, m_width, wxMENU_HEIGHT );                menu_bar->SetInvokingWindow(active_child_frame);            }        }        m_justInserted = false;        return;    }    wxFrame::OnInternalIdle();    wxMDIChildFrame *active_child_frame = GetActiveChild();    bool visible_child_menu = false;    wxWindowList::compatibility_iterator node = m_clientWindow->GetChildren().GetFirst();    while (node)    {        wxMDIChildFrame *child_frame = wxDynamicCast( node->GetData(), wxMDIChildFrame );        if ( child_frame )        {            wxMenuBar *menu_bar = child_frame->m_menuBar;            if ( menu_bar )            {                if (child_frame == active_child_frame)                {                    if (menu_bar->Show(true))                    {                        menu_bar->m_width = m_width;                        menu_bar->m_height = wxMENU_HEIGHT;                        gtk_pizza_set_size( GTK_PIZZA(m_mainWidget),                                            menu_bar->m_widget,                                            0, 0, m_width, wxMENU_HEIGHT );                        menu_bar->SetInvokingWindow( child_frame );                    }                    visible_child_menu = true;                }                else                {                    if (menu_bar->Show(false))                    {                        menu_bar->UnsetInvokingWindow( child_frame );                    }                }            }        }        node = node->GetNext();    }    /* show/hide parent menu bar as required */    if ((m_frameMenuBar) &&        (m_frameMenuBar->IsShown() == visible_child_menu))    {        if (visible_child_menu)        {            m_frameMenuBar->Show( false );            m_frameMenuBar->UnsetInvokingWindow( this );        }        else        {            m_frameMenuBar->Show( true );            m_frameMenuBar->SetInvokingWindow( this );            m_frameMenuBar->m_width = m_width;            m_frameMenuBar->m_height = wxMENU_HEIGHT;            gtk_pizza_set_size( GTK_PIZZA(m_mainWidget),                                m_frameMenuBar->m_widget,                                0, 0, m_width, wxMENU_HEIGHT );        }    }}

void csFrame::OnSaveUpdate(wxUpdateUIEvent& event){    event.Enable( (GetActiveChild() != NULL) );}

void DeviceFrame::OnDeviceCloseCurrentWindow(wxCommandEvent&) {  wxMDIChildFrame* frame = GetActiveChild();  if (frame) {    frame->Close();  }}

void wxMDIParentFrame::OnInternalIdle(){    /* if a MDI child window has just been inserted       it has to be brought to the top in idle time. we       simply set the last notebook page active as new       pages can only be appended at the end */    if (m_justInserted)    {        GtkNotebook *notebook = GTK_NOTEBOOK(m_clientWindow->m_widget);        gtk_notebook_set_current_page(notebook, -1);        /* need to set the menubar of the child */        wxMDIChildFrame *active_child_frame = GetActiveChild();        if (active_child_frame != NULL)        {            wxMenuBar *menu_bar = active_child_frame->m_menuBar;            if (menu_bar)            {                menu_bar->Attach(active_child_frame);            }        }        m_justInserted = false;        return;    }    wxFrame::OnInternalIdle();    wxMDIChildFrame *active_child_frame = GetActiveChild();    bool visible_child_menu = false;    wxWindowList::compatibility_iterator node = m_clientWindow->GetChildren().GetFirst();    while (node)    {        wxMDIChildFrame *child_frame = wxDynamicCast( node->GetData(), wxMDIChildFrame );        if ( child_frame )        {            wxMenuBar *menu_bar = child_frame->m_menuBar;            if ( menu_bar )            {                if (child_frame == active_child_frame)                {                    if (menu_bar->Show(true))                    {                        // Attach() asserts if we call it for an already                        // attached menu bar so don't do it if we're already                        // associated with this frame (it would be nice to get                        // rid of this check and ensure that this doesn't                        // happen...)                        if ( menu_bar->GetFrame() != child_frame )                            menu_bar->Attach( child_frame );                    }                    visible_child_menu = true;                }                else                {                    if (menu_bar->Show(false))                    {                        menu_bar->Detach();                    }                }            }        }        node = node->GetNext();    }    /* show/hide parent menu bar as required */    if ((m_frameMenuBar) &&        (m_frameMenuBar->IsShown() == visible_child_menu))    {        if (visible_child_menu)        {            m_frameMenuBar->Show( false );            m_frameMenuBar->Detach();        }        else        {            m_frameMenuBar->Show( true );            m_frameMenuBar->Attach( this );        }    }}

void CSAGA_Frame::On_Frame_Close_All_UI(wxUpdateUIEvent &event){	event.Enable(GetActiveChild() != NULL);}