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Clickable QLabel: Difference between revisions
(Cleanup) |
Marco Sulla (talk | contribs) (Added includes, changed constructor) |
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Line 7: | Line 7: | ||
<code> | <code> | ||
class ClickableLabel : public QLabel | #ifndef CLICKABLELABEL_H | ||
{ | #define CLICKABLELABEL_H | ||
Q_OBJECT | |||
#include <QLabel> | |||
#include <QWidget> | |||
#include <Qt> | |||
class ClickableLabel : public QLabel { | |||
Q_OBJECT | |||
public: | public: | ||
explicit ClickableLabel( | explicit ClickableLabel(QWidget* parent = Q_NULLPTR, Qt::WindowFlags f = Qt::WindowFlags()); | ||
~ClickableLabel(); | ~ClickableLabel(); | ||
signals: | signals: | ||
void clicked(); | void clicked(); | ||
protected: | protected: | ||
void mousePressEvent(QMouseEvent* event); | void mousePressEvent(QMouseEvent* event); | ||
}; | }; | ||
#endif // CLICKABLELABEL_H | |||
</code> | </code> | ||
Line 23: | Line 36: | ||
<code> | <code> | ||
ClickableLabel::ClickableLabel( | #include "clickablelabel.h" | ||
: QLabel(parent) | |||
{ | ClickableLabel::ClickableLabel(QWidget* parent, Qt::WindowFlags f) | ||
: QLabel(parent) { | |||
} | } | ||
ClickableLabel::~ClickableLabel() | ClickableLabel::~ClickableLabel() {} | ||
{ | |||
} | |||
void ClickableLabel::mousePressEvent(QMouseEvent* event) | void ClickableLabel::mousePressEvent(QMouseEvent* event) { | ||
{ | |||
emit clicked(); | emit clicked(); | ||
} | } | ||
</code> | </code> | ||
Revision as of 07:13, 18 May 2017
A "clicked" signal may sometimes be required from a label, but there is no "clicked" signal emitted by QLabel. You can work around this easily by making a QPushButton like a label by setting the 'flat' property.
However, if there are other properties of a QLabel object that you need, here is a code snippet for a custom QLabel which can emit a signal: 'clicked'. In other words, a Clickable QLabel!
Header
#ifndef CLICKABLELABEL_H
#define CLICKABLELABEL_H
#include <QLabel>
#include <QWidget>
#include <Qt>
class ClickableLabel : public QLabel {
Q_OBJECT
public:
explicit ClickableLabel(QWidget* parent = Q_NULLPTR, Qt::WindowFlags f = Qt::WindowFlags());
~ClickableLabel();
signals:
void clicked();
protected:
void mousePressEvent(QMouseEvent* event);
};
#endif // CLICKABLELABEL_H
Source
#include "clickablelabel.h"
ClickableLabel::ClickableLabel(QWidget* parent, Qt::WindowFlags f)
: QLabel(parent) {
}
ClickableLabel::~ClickableLabel() {}
void ClickableLabel::mousePressEvent(QMouseEvent* event) {
emit clicked();
}
What we do here is simple: Catch the mouse press event on the label. Then emit 'clicked' signal. We could as well make the signal be emitted when mouse gets released. This is let to be a decision of the developer.