I have created a custom Widget,it has to be displayed as a popup menu when click on the ToolButton. How I can do this in Qt 5.1.1?
You should create your custom QWidgetAction to add to the popup menu.
This is a sample QWidgetAction :
#include <QWidgetAction>
class myCustomWidgetAction: public QWidgetAction
{
Q_OBJECT
public:
explicit myCustomWidgetAction(QWidget * parent);
protected:
QWidget * createWidget(QWidget *parent);
};
myCustomWidgetAction::myCustomWidgetAction(QWidget * parent):QWidgetAction(parent) {
}
QWidget * myCustomWidgetAction::createWidget(QWidget *parent){
myCustomWidget * widget=new myCustomWidget(parent);
return widget;
}
You can then add your widget to the tool button to be displayed in a popup menu:
myCustomWidgetAction * widgetAction = new myCustomWidgetAction(this);
ui->toolButton->addAction(widgetAction);
myCustomWidget can be any widget. You can add multiple instances of myCustomWidgetAction to the toolButton.
Related
I am new in qt I want to create a button when I right click
There is my code:
void MainWindow::right_clicked(QMouseEvent *event)
{
if(event->button() == Qt::RightButton)
{
QPushButton *item = new QPushButton();
item->setIcon(QIcon(":/images/7928748-removebg-preview(1).ico"));
item->setIconSize(QSize(32, 32));
item->setGeometry(QRect(QPoint(event->x(), event->y()), QSize(32, 32)));
}
}
But nothing appears
To capture any mouse event in a QWidget you must override the mousePressEvent method.
class MainWindow : public QMainWindow
{
Q_OBJECT
protected:
void mousePressEvent(QMouseEvent *event);
};
And in the mainwindow.cpp, implement it as follows:
void MainWindow::mousePressEvent(QMouseEvent *event)
{
if(event->button() == Qt::RightButton) {
// make mainwindow parent of this button by passing "this" pointer
QPushButton *item = new QPushButton(QIcon(":/images/close-button-icon"), "", this);
// set button position to the location of mouse click
item->setGeometry(QRect(QPoint(event->x()-16, event->y()-16), QSize(32, 32)));
item->show();
}
}
If you don't save the pointer to QPushButton, then you will not be able to use it afterwards.
I'm trying to create a widget which, when shown, it will intercept any mouse clicks, process them, but then forward the click to the widget that was under the mouse when it was clicked. I've created a class that represents this widget; all it does for now is capture mouse release events, hide itself and post the event to the widget the click was intended for using QApplication::postEvent:
class Overlay : public QWidget
{
Q_OBJECT
public:
Overlay(QWidget* parent)
: QWidget(parent){}
protected:
void mouseReleaseEvent(QMouseEvent* event)
{
hide();
auto child = parentWidget()->childAt(event->pos()); // get the child widget the event was intended for
auto e = new QMouseEvent(*event);
if(child) QCoreApplication::postEvent(child, e); // why doesn't this have any effect?
event->accept();
}
void paintEvent(QPaintEvent* event)
{
QPainter p(this);
p.fillRect(rect(), QColor(0,0,0,150));
}
};
Unfortunately, the call to postEvent doesn't seem to have any effect at all. Here is an example where I'm setting up some child widgets; clicking on any widget will print something out:
class Widget : public QWidget
{
Q_OBJECT
public:
Widget(QWidget *parent = nullptr)
{
m_overlay = new Overlay(this);
m_overlay->hide();
auto button = new QPushButton("Add overlay");
auto button2 = new QPushButton("PushButton");
auto list = new QListWidget();
list->addItems(QStringList() << "item1" << "item2" << "item3");
connect(list, &QListWidget::itemClicked, [](const QListWidgetItem* item)
{
qDebug() << item->text();
});
connect(button2, &QPushButton::clicked, []()
{
qDebug() << "Button clicked";
});
connect(button, &QPushButton::clicked, [this]()
{
m_overlay->setGeometry(rect());
m_overlay->raise();
m_overlay->show();
});
auto layout = new QVBoxLayout(this);
layout->addWidget(list);
layout->addWidget(button);
layout->addWidget(button2);
}
public:
~Widget(){}
private:
Overlay* m_overlay;
};
I've confirmed that clicks on the overlay are captured and the overlay is hidden as intended but the event is not propagated to the underlying widget. Using QApplication::sendEvent doesn't work either. What am I missing?
Using Qt 5.15.1 on MacOS 11.2.3. Thanks
I'm struggeling with telling a QScitilla textEdit that is the main widget of my MainWindow app to accept showing a personalized context menu on right-clicking the mouse.
What works fine if I use a standard Qt5 textEdit fails if used with the QScintilla alternative. I tried it with defining a user menu from some actions:
void MainWindow::contextMenuEvent(QContextMenuEvent *event)
{
QMenu menu(this);
menu.addAction(cutAct);
menu.addAction(copyAct);
menu.addAction(pasteAct);
menu.exec(event->globalPos());
}
#endif // QT_NO_CONTEXTMENU
reacting on QContextMenuEvent, but the menu only shows up when I right-click an element of the MainWindow instead of the QScintilla textEdit. When I do within the textEdit, only the standard cut/copy/paste menu is shown.
How to implement that for QScintilla textEdit?
There are two methods:
Method 1: set Qt::CustomContextMenu for context menu policy of QScintilla text edit :
textEdit->setContextMenuPolicy( Qt::CustomContextMenu );
connect(textEdit, SIGNAL(customContextMenuRequested(const QPoint &)),
this, SLOT(ShowContextMenu(const QPoint &)));
}
void MainWindow::ShowContextMenu(const QPoint &pos)
{
QMenu contextMenu(tr("Context menu"), this);
QAction action1("Action 1", this);
connect(&action1, &QAction::triggered, this, []{
qDebug() << "On action 1 click !!!";
});
contextMenu.addAction(&action1);
contextMenu.exec(mapToGlobal(pos));
}
Method 2: Define a subclass of QScintilla then redefine the override function contextMenuEvent :
class MyQsciScintilla : public QsciScintilla
{
Q_OBJECT
public:
explicit MyQsciScintilla(QWidget *parent = nullptr);
void contextMenuEvent(QContextMenuEvent *event);
//....
};
void MyQsciScintilla::contextMenuEvent(QContextMenuEvent *event)
{
QMenu *menu = createStandardContextMenu();
menu->addAction(tr("My Menu Item"));
//...
menu->exec(event->globalPos());
delete menu;
}
I have a simple Qt toolbar with text only button Action:
MainWindow::MainWindow(QWidget* parent) : QMainWindow(parent)
{
QToolBar* toolBar = new QToolBar(this);
QAction* action = toolBar->addAction("&Action");
QObject::connect(action, SIGNAL(triggered()), this, SLOT(onAction()));
action->setShortcut(QKeySequence("ctrl+a"));
addToolBar(toolBar);
}
I would like to have A in Action underlined to reflect its role as a shortcut key. How to accomplish that?
Standard QAction widget (it is a QToolButton actually) uses stripped version of its text for display: "&Menu Option..." becomes "Menu Option".
You can create a custom QAction widget which does not use stripped text by subclassing QWidgetAction:
MyAction::MyAction(QObject *parent) :
QWidgetAction(parent)
{
}
QWidget* MyAction::createWidget(QWidget *parent)
{
QToolButton *tb = new QToolButton(parent);
tb->setDefaultAction(this);
tb->setText(this->text());// override text stripping
tb->setFocusPolicy(Qt::NoFocus);
return tb;
}
In your MainWindow constructor use it as follows:
MainWindow(QWidget* parent=0) : QMainWindow(parent)
{
QToolBar* toolBar = new QToolBar(this);
MyAction* action = new MyAction();
action->setText("&Action");
action->setShortcut(QKeySequence(tr("ctrl+a","Action")));
toolBar->addAction(action);
QObject::connect(action, SIGNAL(triggered()), this, SLOT(onAction()));
addToolBar(toolBar);
}
Appearence of underline shortcut letters depends on your application style.
Here is an example of a custom style that will force shortcut underline display:
class MyStyle : public QProxyStyle
{
public:
MyStyle();
int styleHint(StyleHint hint,
const QStyleOption *option,
const QWidget *widget,
QStyleHintReturn *returnData) const;
};
int MyStyle::styleHint(QStyle::StyleHint hint,
const QStyleOption *option,
const QWidget *widget,
QStyleHintReturn *returnData) const
{
if (hint == QStyle::SH_UnderlineShortcut)
{
return 1;
}
return QProxyStyle::styleHint(hint, option, widget, returnData);
}
Then you should set that style to your application:
int main(int argc, char *argv[])
{
QApplication a(argc, argv);
a.setStyle(new MyStyle);
Widget w;
w.show();
return a.exec();
}
I want to be able to show ToolTips for QMenu items (QActions). The best I have achieved is to connect the hovered signal of the QAction to a QTooltip show:
connect(action, &QAction::hovered, [=]{
QToolTip::showText(QCursor::pos(), text, this);
});
The problem is that sometimes the program will position the tooltip below the menu, specially when changing menus.
Is there any way to force the tooltip to show on top?
Since Qt 5.1, you can use QMenu's property toolTipsVisible, which is by default set to false.
See the related Qt suggestion.
You can subclass QMenu and reimplementing QMenu::event() to intercept the QEvent::ToolTip event and call QToolTip::showText to set the tooltip for the active action :
#include <QtGui>
class Menu : public QMenu
{
Q_OBJECT
public:
Menu(){}
bool event (QEvent * e)
{
const QHelpEvent *helpEvent = static_cast <QHelpEvent *>(e);
if (helpEvent->type() == QEvent::ToolTip && activeAction() != 0)
{
QToolTip::showText(helpEvent->globalPos(), activeAction()->toolTip());
} else
{
QToolTip::hideText();
}
return QMenu::event(e);
}
};
Now you can use your custom menu like :
Menu *menu = new Menu();
menu->setTitle("Test menu");
menuBar()->addMenu(menu);
QAction *action1 = menu->addAction("First");
action1->setToolTip("First action");
QAction *action2 = menu->addAction("Second");
action2->setToolTip("Second action");