make a .jpg or .bmp picture into a widget...?

**JimDaniel** · 11th June 2008, 15:19

Okay, I finally whipped up a test app, and found some problems. Here is the working program:

Qt Code:

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#ifndef BLINKINGICON_H
#define BLINKINGICON_H
 
#include <QtGui>
#include <QtCore>
 
class BlinkingIcon : public QWidget
{
	Q_OBJECT
 
public:
	BlinkingIcon(QWidget * parent = 0);
	virtual ~BlinkingIcon();
 
public slots:
	void startBlinking();
 
private:
	QLabel * m_display_image;
};
 
#endif // BLINKINGICON_H
 
 
#include "blinkingicon.h"
 
BlinkingIcon::BlinkingIcon(QWidget * parent) : QWidget(parent)
{
	this->setWindowTitle(tr("My Blinking Icon"));    
	this->setFixedSize(50, 50);
 
	m_display_image = new QLabel(this);        
	m_display_image->setScaledContents(true); 
 
	this->startBlinking(); 
 
	QTimer * timer = new QTimer(this);    
	connect(timer, SIGNAL(timeout()), this, SLOT(startBlinking()));
	timer->start(1000);
}
 
BlinkingIcon::~BlinkingIcon()
{}
 
void BlinkingIcon::startBlinking()
{
	static bool on = false;
 
	m_display_image->clear();
 
	if (on)
	{
		m_display_image->setPixmap(QPixmap("C:/my_second_image.png"));
		on = false;
	}
	else
	{
		m_display_image->setPixmap(QPixmap("C:/my_first_image.png"));
		on = true;
	}
 
	m_display_image->resize(50, 50);
}

#ifndef BLINKINGICON_H
#define BLINKINGICON_H

#include <QtGui>
#include <QtCore>

class BlinkingIcon : public QWidget
{
	Q_OBJECT

public:
	BlinkingIcon(QWidget * parent = 0);
	virtual ~BlinkingIcon();

public slots:
	void startBlinking();

private:
	QLabel * m_display_image;
};

#endif // BLINKINGICON_H


#include "blinkingicon.h"

BlinkingIcon::BlinkingIcon(QWidget * parent) : QWidget(parent)
{
	this->setWindowTitle(tr("My Blinking Icon"));    
	this->setFixedSize(50, 50);

	m_display_image = new QLabel(this);        
	m_display_image->setScaledContents(true); 

	this->startBlinking(); 

	QTimer * timer = new QTimer(this);    
	connect(timer, SIGNAL(timeout()), this, SLOT(startBlinking()));
	timer->start(1000);
}

BlinkingIcon::~BlinkingIcon()
{}

void BlinkingIcon::startBlinking()
{
	static bool on = false;

	m_display_image->clear();

	if (on)
	{
		m_display_image->setPixmap(QPixmap("C:/my_second_image.png"));
		on = false;
	}
	else
	{
		m_display_image->setPixmap(QPixmap("C:/my_first_image.png"));
		on = true;
	}

	m_display_image->resize(50, 50);
}

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The first problem was that in your header file, you need to put your slot methods under:

public slots:

(or protected/private, depending who you want to be able to call)

After I changed that it worked fine, although sometimes the timer.second() test you were doing would not work as expected, so I changed the test to what you see now...

**mynahz** · 12th June 2008, 10:00

oh yes! it works perfect!

Thank you, JimDaniel!!!

**mynahz** · 7th July 2008, 08:32

Hi to all once again... I have a question related to this again... I have another way, of putting the picture(.png) into the QLabel within QT designer, but I am having problems making the image show/hide when I want them to. Do I use the functions from QWidget, show() and hide()? If so, then I have no idea why it doesn't hide my label when i call the hide function...

I will try to upload my project file soon just clarify how I get my picture up into QT, as currently I can only compress it into .rar file.

Also, just want to find out, anyone using canbus in QT? I am currently working on a project to configure a display for a vehicle and I have problems getting candata from the canbus and processing the candata such that my icon will blink when specific candata are received...

Thanks in advance to all.