Getting mouse click location of a label in qt
I googled around and found this forum thread in which the OP seems to have had the exact problem I am having. The question is, how would I inherit from QLabel
and reimplement the mousepressed event? I'm guessing it would be something like this:
class CustomLabel : public QLabel
{
public:
//what about the constructors?
void mousePressEvent ( QMouseEvent * ev );
}
void CustomLabel::mousePressEvent ( QMouseEvent * ev )
{
QPoint = ev->pos();
//I want to have another function get th开发者_StackOverflowe event position.
//How would I achieve this? It's void!
//Is there perhaps some way to set up a signal and slot with the position?
}
And after I have successfully created a CustomLabel
class, how would I be able to put it in design view?
Yes, you can set up a signal on your CustomLabel
class and have your overridden version of mousePressEvent
emit it. i.e.
class CustomLabel : public QLabel
{
Q_OBJECT
signals:
void mousePressed( const QPoint& );
public:
CustomLabel( QWidget* parent = 0, Qt::WindowFlags f = 0 );
CustomLabel( const QString& text, QWidget* parent = 0, Qt::WindowFlags f = 0 );
void mousePressEvent( QMouseEvent* ev );
};
void CustomLabel::mousePressEvent( QMouseEvent* ev )
{
const QPoint p = ev->pos();
emit mousePressed( p );
}
CustomLabel::CustomLabel( QWidget * parent, Qt::WindowFlags f )
: QLabel( parent, f ) {}
CustomLabel::CustomLabel( const QString& text, QWidget* parent, Qt::WindowFlags f )
: QLabel( text, parent, f ) {}
The constructors just mimic those of the base QLabel
and therefore simply pass their arguments straight on to the corresponding base constructors.
just like this :D
void CustomLabel::mousePressEvent(QMouseEvent *ev)
{
QString x = QString::number(ev->x());
QString y = QString::number(ev->y());
qDebug() << x << "," << y;
}
Is it just me, or doesn't QMouseEvent
already give the information you need?
int QMouseEvent::x () const
Returns the x position of the mouse cursor, relative to the widget that received the event.
See also y() and pos().
int QMouseEvent::y () const
Returns the y position of the mouse cursor, relative to the widget that received the event.
See also x() and pos().
Ref: http://doc.qt.nokia.com/4.7.old/qmouseevent.html#x
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