{"id":11707,"date":"2021-02-02T09:10:09","date_gmt":"2021-02-02T09:10:09","guid":{"rendered":"http:\/\/blog.bachi.net\/?p=11707"},"modified":"2021-02-02T09:50:23","modified_gmt":"2021-02-02T09:50:23","slug":"qt-popup-overlay-window","status":"publish","type":"post","link":"https:\/\/blog.bachi.net\/?p=11707","title":{"rendered":"Qt Popup\/Overlay Window"},"content":{"rendered":"

QApplication::activeModalWidget()<\/code><\/a>
\nA modal widget is a special top-level widget which is a subclass of QDialog that specifies the modal parameter of the constructor as true. A modal widget must be closed before the user can continue with other parts of the program.<\/p>\n

QApplication::activePopupWidget()<\/code><\/a>
\nA popup widget is a special top-level widget that sets the Qt::WType_Popup<\/code> widget flag, e.g. the QMenu <\/code>widget. When the application opens a popup widget, all events are sent to the popup. Normal widgets and modal widgets cannot be accessed before the popup widget is closed.<\/p>\n

\n

<\/p>\n

Questions<\/h4>\n

Custom popup widget<\/a>
\nHow would I go about making a overlay widget<\/a><\/p>\n

Code<\/h4>\n
\r\nvoid QCompleter::setPopup(QAbstractItemView *popup)\r\n{\r\n    Q_D(QCompleter);\r\n    Q_ASSERT(popup != nullptr);\r\n    if (d->popup) {\r\n        QObject::disconnect(d->popup->selectionModel(), nullptr, this, nullptr);\r\n        QObject::disconnect(d->popup, nullptr, this, nullptr);\r\n    }\r\n    if (d->popup != popup)\r\n        delete d->popup;\r\n    if (popup->model() != d->proxy)\r\n        popup->setModel(d->proxy);\r\n     popup->hide();\r\n\r\n    Qt::FocusPolicy origPolicy = Qt::NoFocus;\r\n    if (d->widget)\r\n        origPolicy = d->widget->focusPolicy();\r\n\r\n    \/\/ Mark the widget window as a popup, so that if the last non-popup window is closed by the\r\n    \/\/ user, the application should not be prevented from exiting. It needs to be set explicitly via\r\n    \/\/ setWindowFlag(), because passing the flag via setParent(parent, windowFlags) does not call\r\n    \/\/ QWidgetPrivate::adjustQuitOnCloseAttribute(), and causes an application not to exit if the\r\n    \/\/ popup ends up being the last window.\r\n    popup->setParent(nullptr);\r\n    popup->setWindowFlag(Qt::Popup);\r\n    popup->setFocusPolicy(Qt::NoFocus);\r\n    if (d->widget)\r\n        d->widget->setFocusPolicy(origPolicy);\r\n\r\n    popup->setFocusProxy(d->widget);\r\n    popup->installEventFilter(this);\r\n    popup->setItemDelegate(new QCompleterItemDelegate(popup));\r\n#if QT_CONFIG(listview)\r\n    if (QListView *listView = qobject_cast<QListView *>(popup)) {\r\n        listView->setModelColumn(d->column);\r\n    }\r\n#endif\r\n\r\n    QObject::connect(popup, SIGNAL(clicked(QModelIndex)),\r\n                     this, SLOT(_q_complete(QModelIndex)));\r\n    QObject::connect(this, SIGNAL(activated(QModelIndex)),\r\n                     popup, SLOT(hide()));\r\n\r\n    QObject::connect(popup->selectionModel(), SIGNAL(selectionChanged(QItemSelection,QItemSelection)),\r\n                     this, SLOT(_q_completionSelected(QItemSelection)));\r\n    d->popup = popup;\r\n}\r\n\r\nvoid QCompleterPrivate::showPopup(const QRect& rect)\r\n{\r\n    const QRect screen = QWidgetPrivate::availableScreenGeometry(widget);\r\n    Qt::LayoutDirection dir = widget->layoutDirection();\r\n    QPoint pos;\r\n    int rh, w;\r\n    int h = (popup->sizeHintForRow(0) * qMin(maxVisibleItems, popup->model()->rowCount()) + 3) + 3;\r\n    QScrollBar *hsb = popup->horizontalScrollBar();\r\n    if (hsb && hsb->isVisible())\r\n        h += popup->horizontalScrollBar()->sizeHint().height();\r\n\r\n    if (rect.isValid()) {\r\n        rh = rect.height();\r\n        w = rect.width();\r\n        pos = widget->mapToGlobal(dir == Qt::RightToLeft ? rect.bottomRight() : rect.bottomLeft());\r\n    } else {\r\n        rh = widget->height();\r\n        pos = widget->mapToGlobal(QPoint(0, widget->height() - 2));\r\n        w = widget->width();\r\n    }\r\n\r\n    if (w > screen.width())\r\n        w = screen.width();\r\n    if ((pos.x() + w) > (screen.x() + screen.width()))\r\n        pos.setX(screen.x() + screen.width() - w);\r\n    if (pos.x() < screen.x())\r\n        pos.setX(screen.x());\r\n\r\n    int top = pos.y() - rh - screen.top() + 2;\r\n    int bottom = screen.bottom() - pos.y();\r\n    h = qMax(h, popup->minimumHeight());\r\n    if (h > bottom) {\r\n        h = qMin(qMax(top, bottom), h);\r\n\r\n        if (top > bottom)\r\n            pos.setY(pos.y() - h - rh + 2);\r\n    }\r\n\r\n    popup->setGeometry(pos.x(), pos.y(), w, h);\r\n\r\n    if (!popup->isVisible())\r\n        popup->show();\r\n}\r\n<\/pre>\n
\n
<\/p>\n
Transparent\/Alpha Background<\/h1>\n
QDialog with transparent background color<\/a>
\nHow not to lose the alpha channel<\/a><\/p>\n
\n
<\/p>\n
QML<\/h1>\n
Documentation<\/h4>\n
Qt 5.15 – Qt Quick Controls – Popup Controls<\/a><\/p>\n
Questions<\/h4>\n
Popup item loses opaquness<\/a>
\nhow to set popup background color to transparent<\/a>
\nChange popup background to transparent<\/a>
\n<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"
QApplication::activeModalWidget() A modal widget is a special top-level widget which is a subclass of QDialog that specifies the modal parameter of the constructor as true. A modal widget must be closed before the user can continue with other parts of the program. QApplication::activePopupWidget() A popup widget is a special top-level widget that sets the Qt::WType_Popup […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"class_list":["post-11707","post","type-post","status-publish","format-standard","hentry","category-uncategorized"],"_links":{"self":[{"href":"https:\/\/blog.bachi.net\/index.php?rest_route=\/wp\/v2\/posts\/11707","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/blog.bachi.net\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/blog.bachi.net\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/blog.bachi.net\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/blog.bachi.net\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=11707"}],"version-history":[{"count":4,"href":"https:\/\/blog.bachi.net\/index.php?rest_route=\/wp\/v2\/posts\/11707\/revisions"}],"predecessor-version":[{"id":11715,"href":"https:\/\/blog.bachi.net\/index.php?rest_route=\/wp\/v2\/posts\/11707\/revisions\/11715"}],"wp:attachment":[{"href":"https:\/\/blog.bachi.net\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=11707"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/blog.bachi.net\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=11707"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/blog.bachi.net\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=11707"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}