QtToolBar with underlined shortcut key in button text - c++

Question

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?

Answer 1

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();
}