DoubleClick on QLabel - c++

Question

I have read this How to distinguish between mouseReleaseEvent and mousedoubleClickEvent on QGrapnhicsScene and this Distinguish between single and double click events in Qt in order to solve my problem. But they do not work. I created a class QLabel:
mouselabel.h
#ifndef MOUSELABEL_H
#define MOUSELABEL_H
#include <QLabel>
#include <QMouseEvent>
#include <QEvent>
#include <QDebug>
class MouseLabel : public QLabel
{
Q_OBJECT
public:
explicit MouseLabel(QWidget *parent = 0);
void mouseMoveEvent(QMouseEvent *event);
void mousePressEvent(QMouseEvent *event);
void mouseReleaseEvent(QMouseEvent *event);
void mouseDoubleClickEvent(QMouseEvent *event);
void leaveEvent(QMouseEvent *);
int x, y;
signals:
void Mouse_Pressed();
void Mouse_Position();
void Mouse_Left();
void Mouse_Release();
void Mouse_DoubleClick();
public slots:
};
#endif // MOUSELABEL_H
mouselabel.cpp
#include "mouselabel.h"
MouseLabel::MouseLabel(QWidget *parent) :
QLabel(parent)
{
}
void MouseLabel::mouseMoveEvent(QMouseEvent *event) {
this->x = event->x();
this->y = event->y();
emit Mouse_Position();
}
void MouseLabel::mousePressEvent(QMouseEvent *event)
{
emit Mouse_Pressed();
}
void MouseLabel::mouseReleaseEvent(QMouseEvent *event)
{
emit Mouse_Release();
}
void MouseLabel::mouseDoubleClickEvent(QMouseEvent *event)
{
emit Mouse_DoubleClick();
}
void MouseLabel::leaveEvent(QMouseEvent *)
{
emit Mouse_Left();
}
As described in the two links, in order to distinguish between a click and a double click, I created a timer and it starts when a mouserelease event happens and it stops when there is a double click mouse. But, this does not work. Can you help me to solve the problem?

Answer 1

The lightest possible solution is using a QBasicTimer, just have those 2 methods overloaded and the timer in your widget:
void mouseReleaseEvent(QMouseEvent *) {
if (timer.isActive()) {
timer.stop();
qDebug() << "double click";
}
else {
timer.start(300, this);
}
}
void timerEvent(QTimerEvent *) {
timer.stop();
qDebug() << "single click";
}
QBasicTimer timer;
The downside is a timer approach delays the single click, which is kind of annoying, but you could mask that, for example for selecting objects, using the mousePressEvent for immediate response.