QImage and drawImage method

[ally]

thank you, but init method is called one time only when application start so memory for any image is allocated only one time. Isn't it?
I also need to make a couple of them blinking so I prefer to load images only one time and paint when needed :

void MiaClasse::init(){
 
image1 = new QImage;
image1->load("resources/images/image1.png");
 
image2 = new QImage;
image2->load("resources/images/image2.png");
 
blink = false;
 
}
 
void MiaClasse::letItBlink(){
 
blink = !blink;
repaint();
 
}
 
void MiaClasse:: paintEvent(QPaintEvent *)
{
QPainter painter(this);
 
painter.drawImage(155, 130, *image1);
 
if(blink)
painter.drawImage(155, 130, *image2);
}

void MiaClasse::init(){

image1 = new QImage;
image1->load("resources/images/image1.png");

image2 = new QImage;
image2->load("resources/images/image2.png");

blink = false;

}

void MiaClasse::letItBlink(){

blink = !blink;
repaint();

}

void MiaClasse:: paintEvent(QPaintEvent *)
{
QPainter painter(this);

painter.drawImage(155, 130, *image1);

if(blink)
painter.drawImage(155, 130, *image2);
}

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[yeye_olive]

You current design works; loading the images once, upon initialization, instead of every time the widget is painted is the right way. I was not suggesting changing that, quite the contrary.

Instead of allocating QImages on the heap, you could allocate QPixmaps directly with the MiaClasse:

class MiaClasse /* ... */ {
/* ... */
private:
  QPixmap image1;
  QPixmap image2;
}
 
void MiaClasse::init(){
  image1.load("resources/images/image1.png");
  image2.load("resources/images/image2.png");
  blink = false;
}
 
void MiaClasse::letItBlink(){
  blink = !blink;
  update(); // Call this instead of QWidget::repaint()
}
 
void MiaClasse:: paintEvent(QPaintEvent *) {
  QPainter painter(this);
  painter.drawPixmap(155, 130, image1);
  if(blink)
    painter.drawPixmap(155, 130, image2);
}

class MiaClasse /* ... */ {
/* ... */
private:
  QPixmap image1;
  QPixmap image2;
}

void MiaClasse::init(){
  image1.load("resources/images/image1.png");
  image2.load("resources/images/image2.png");
  blink = false;
}

void MiaClasse::letItBlink(){
  blink = !blink;
  update(); // Call this instead of QWidget::repaint()
}
 
void MiaClasse:: paintEvent(QPaintEvent *) {
  QPainter painter(this);
  painter.drawPixmap(155, 130, image1);
  if(blink)
    painter.drawPixmap(155, 130, image2);
}

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