C++ QMenu::installEventFilter方法代码示例

void CLoginButton::menuCreate() {
    QMenu* menu = new QMenu(this);

    QWidget *w = new QWidget(this);
    ui = new Ui::loginWidget;
    ui->setupUi(w);

    ui->toolButton->setEnabled(false);
    connect(ui->lineEdit, &QLineEdit::textChanged,
            this, &CLoginButton::usernameCheck);
    connect(ui->toolButton, &QToolButton::clicked,
            this, &CLoginButton::login);

    QVBoxLayout *vlayout = new QVBoxLayout;
    vlayout->addWidget(w);
    menu->setLayout(vlayout);

    QPixmap pixmap(":/back/ui/back/combox.png");
    menu->setMask(pixmap.mask());
    menu->setStyleSheet("color:white; background-color: rgb(85, 92, 120);");
    menu->installEventFilter(this);

    setMenu(menu);
}

void KrBookmarkHandler::buildMenu(KrBookmark *parent, QMenu *menu)
{
    static int inSecondaryMenu = 0; // used to know if we're on the top menu

    // run the loop twice, in order to put the folders on top. stupid but easy :-)
    // note: this code drops the separators put there by the user
    QListIterator<KrBookmark *> it(parent->children());
    while (it.hasNext()) {
        KrBookmark *bm = it.next();

        if (!bm->isFolder()) continue;
        QMenu *newMenu = new QMenu(menu);
        newMenu->setIcon(QIcon(krLoader->loadIcon(bm->iconName(), KIconLoader::Small)));
        newMenu->setTitle(bm->text());
        QAction *menuAction = menu->addMenu(newMenu);
        QVariant v;
        v.setValue<KrBookmark *>(bm);
        menuAction->setData(v);

        ++inSecondaryMenu;
        buildMenu(bm, newMenu);
        --inSecondaryMenu;
    }

    it.toFront();
    while (it.hasNext()) {
        KrBookmark *bm = it.next();
        if (bm->isFolder()) continue;
        if (bm->isSeparator()) {
            menu->addSeparator();
            continue;
        }
        menu->addAction(bm);
        CONNECT_BM(bm);
    }

    if (!inSecondaryMenu) {
        KConfigGroup group(krConfig, "Private");
        bool hasPopularURLs = group.readEntry("BM Popular URLs", true);
        bool hasTrash       = group.readEntry("BM Trash",        true);
        bool hasLan         = group.readEntry("BM Lan",          true);
        bool hasVirtualFS   = group.readEntry("BM Virtual FS",   true);
        bool hasJumpback    = group.readEntry("BM Jumpback",     true);

        if (hasPopularURLs) {
            menu->addSeparator();

            // add the popular links submenu
            QMenu *newMenu = new QMenu(menu);
            newMenu->setTitle(i18n("Popular URLs"));
            newMenu->setIcon(QIcon(krLoader->loadIcon("folder-bookmark", KIconLoader::Small)));
            QAction *bmfAct  = menu->addMenu(newMenu);
            _specialBookmarks.append(bmfAct);
            // add the top 15 urls
#define MAX 15
            QList<QUrl> list = _mainWindow->popularUrls()->getMostPopularUrls(MAX);
            QList<QUrl>::Iterator it;
            for (it = list.begin(); it != list.end(); ++it) {
                QString name;
                if ((*it).isLocalFile()) name = (*it).path();
                else name = (*it).toDisplayString();
                // note: these bookmark are put into the private collection
                // as to not spam the general collection
                KrBookmark *bm = KrBookmark::getExistingBookmark(name, _privateCollection);
                if (!bm)
                    bm = new KrBookmark(name, *it, _privateCollection);
                newMenu->addAction(bm);
                CONNECT_BM(bm);
            }

            newMenu->addSeparator();
            newMenu->addAction(krPopularUrls);
            newMenu->installEventFilter(this);
        }

        // do we need to add special bookmarks?
        if (SPECIAL_BOOKMARKS) {
            if (hasTrash || hasLan || hasVirtualFS || hasJumpback)
                menu->addSeparator();

            KrBookmark *bm;

            // note: special bookmarks are not kept inside the _bookmarks list and added ad-hoc
            if (hasTrash) {
                bm = KrBookmark::trash(_collection);
                menu->addAction(bm);
                _specialBookmarks.append(bm);
                CONNECT_BM(bm);
            }

            if (hasLan) {
                bm = KrBookmark::lan(_collection);
                menu->addAction(bm);
                _specialBookmarks.append(bm);
                CONNECT_BM(bm);
            }

            if (hasVirtualFS) {
                bm = KrBookmark::virt(_collection);
                menu->addAction(bm);
//.........这里部分代码省略.........

void MainWindow::menuBookmarksAboutToShow()
{
	QMenu *menu = qobject_cast<QMenu*>(sender());

	if (!menu || !menu->menuAction())
	{
		return;
	}

	menu->setObjectName(QLatin1String("bookmarks"));
	menu->installEventFilter(this);

	const int folder = menu->menuAction()->data().toInt();

	if ((folder == 0 && menu->actions().count() == 3) || (folder != 0 && menu->actions().isEmpty()))
	{
		WebBackend *backend = WebBackendsManager::getBackend();
		const QList<BookmarkInformation*> bookmarks = BookmarksManager::getFolder(folder);

		if (folder != 0 && bookmarks.count() > 1)
		{
			QAction *openAllAction = menu->addAction(Utils::getIcon(QLatin1String("document-open-folder")), tr("Open All"));
			openAllAction->setData(folder);

			connect(openAllAction, SIGNAL(triggered()), this, SLOT(actionOpenBookmarkFolder()));

			menu->addSeparator();
		}

		for (int i = 0; i < bookmarks.count(); ++i)
		{
			if (bookmarks.at(i)->type == FolderBookmark || bookmarks.at(i)->type == UrlBookmark)
			{
				QAction *action = menu->addAction(((bookmarks.at(i)->type == FolderBookmark) ? Utils::getIcon(QLatin1String("inode-directory")) : backend->getIconForUrl(QUrl(bookmarks.at(i)->url))), (bookmarks.at(i)->title.isEmpty() ? tr("(Untitled)") : Utils::elideText(QString(bookmarks.at(i)->title).replace(QLatin1Char('&'), QLatin1String("&&")), menu)));
				action->setToolTip(bookmarks.at(i)->description);

				if (bookmarks.at(i)->type == FolderBookmark)
				{
					action->setData(bookmarks.at(i)->identifier);

					if (!bookmarks.at(i)->children.isEmpty())
					{
						action->setMenu(new QMenu());

						connect(action->menu(), SIGNAL(aboutToShow()), this, SLOT(menuBookmarksAboutToShow()));
					}
				}
				else
				{
					action->setData(bookmarks.at(i)->url);

					connect(action, SIGNAL(triggered()), this, SLOT(actionOpenBookmark()));
				}
			}
			else
			{
				menu->addSeparator();
			}
		}
	}
}