Called when the page has been switched.

Example 105. Listening to the switch-page signal

//Create a new notebook
$ntbk = new GtkNotebook();

//Create a first page
$ntbk->append_page(new GtkLabel('Page one'), new GtkLabel('1.'));

    new GtkLabel('This is the second child'),
    new GtkLabel('Second')

    new GtkLabel('Third page'),
    new GtkLabel('3rd')

//the fourth tab has no user-defined label
// get_tab_label_text() will return NULL in this case
$ntbk->append_page(new GtkLabel('IV'));

function onSwitchPage($ntbk, $pointer, $pageNum, $wnd)
    //the number of the newly selected tab is $pageNum
    //use it to get the page child widget
    $pageWidget = $ntbk->get_nth_page($pageNum);
    //now we can use the page child to retrieve the tab label
    $text = $ntbk->get_tab_label_text($pageWidget);
    //show the selected tab's title in the window title

$wnd = new GtkWindow();
//everytime the user switches the tab, call the onSwitchPage function
$ntbk->connect('switch-page', 'onSwitchPage', $wnd);

//The rest of the setup is standard
$wnd->set_default_size(300, -1);
$wnd->connect_simple('destroy', array('Gtk', 'main_quit'));

Callback function

void callback(GtkNotebook notebook, pointer pointer, int page_num);