重写QLabel使其响应单、双击事件

最新推荐文章于 2024-11-18 13:35:26 发布

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本文详细介绍了如何使用Qt框架中的信号与槽机制，通过自定义类Label来实现动态显示文本信息的功能，并包括了鼠标事件处理、定时器应用以及单击与双击事件触发的信号发送。

#ifndef _LABEL_H_
#define _LABEL_H_
#include "QLabel"
#include <QWidget> 
#include "qcoreevent.h"
#include "qevent.h"
#include "qtimer.h"

class Label:public QLabel
{
	Q_OBJECT
public:
	explicit Label(QWidget *parent = 0);
	~Label();
protected:
	void mousePressEvent(QMouseEvent *event);
	void mouseReleaseEvent(QMouseEvent *event);
private:
	bool mouse_press; 
	int clicked_num;
	QTimer* timer;
private slots:
	void SlotTimerOut();
signals:  
	void LabelClicked();  
	void LabelDoubleClicked();  
};


#endif //_LABEL_H_

#include "label.h"

Label::Label( QWidget *parent /*= 0*/ ):QLabel(parent)
{
	mouse_press = false;
	clicked_num = 0;
	timer = new QTimer(this);
	connect(timer,SIGNAL(timeout()),this,SLOT(SlotTimerOut()));   
}

Label::~Label()
{
	delete timer;
}

void Label::mousePressEvent( QMouseEvent *event )
{
	if (event->button() == Qt::LeftButton)
	{
		mouse_press = true;
	}
}

void Label::mouseReleaseEvent( QMouseEvent *event )
{
	if(mouse_press  && this->rect().contains(event->pos()))
	{
		clicked_num++;
		mouse_press = false;
		timer->start(200);
	}
}

void Label::SlotTimerOut()
{
	if (clicked_num == 1)
	{
		emit LabelClicked();
	}
	if (clicked_num >= 2)
	{
		emit LabelDoubleClicked();
	}
	clicked_num = 0;
	timer->stop();
}