Qt cannot save pixmap - c++

Question

Hello i have a strange problem to save pixmap.
My Widget Header
public:
QPixmap *base; //Base Poses
QPixmap *Hair; //Hair
QPixmap *Composited; //Final Composition
bool compisition = false;
void Composite();
My Widget Cpp
At paintEvent
base = &pic;
Hair = &hairs;
if(compisition)
{
QPixmap pix(128,192);
QPainter *p = new QPainter(&pix);
p->drawPixmap(0,0,128,192,*base);
p->drawPixmap(0,0,128,192,*Hair);
Composited = &pix;
compisition = false;
}
void AnimPreview::Composite()
{
compisition = true;
this->update();
}
At main form source
void MainWindow::on_commandLinkButton_clicked()
{
QString file = QFileDialog::getSaveFileName(this,
tr("Save Sprite file"),
"",tr("File PNG (*.png)"));
const QPixmap *pix = ui->SpriteFront->pixmap();
if(!file.isEmpty())
{
QFile files(file);
files.open(QIODevice::WriteOnly);
ui->SpriteFront->Composite();
ui->SpriteFront->Composited->save(&files,"PNG");
}
}
When i try to save a file, the process work but whit on error
An unhandled win32 exception
For more information
complete code here
https://pastebin.com/GtaVCXGf

Answer 1

I have avoided reviewing where the error can be generated since there are many possible sources of the problem, among them the following:
It is not necessary that you create QPixmap pointers since in the end you will have the job of eliminating it from memory.
The same happens with QPainter since it only needs to be a local variable, in addition to that the painting is not done immediately, to be sure that it is painted you must call its end() method.
paintEvent is a protected method, so by design we prefer it to remain so.
It is not necessary to use a QFile to save an image, you can directly pass the filename to it.
Considering all the above, we obtain the following:
*.h
#ifndef ANIMPREVIEW_H
#define ANIMPREVIEW_H
#include <QLabel>
#include <QPixmap>
class AnimPreview : public QLabel
{
public:
AnimPreview(QWidget *parent = 0);
void Rotate(int value);
void Composite();
void Create(int _sex, int _hair);
QPixmap Composited;
private:
int sex = 0;
int hair = 0;
bool draw = true;
int rotation = 0;
const int offsetX = 16;
const int offsetY = 32;
QPixmap base;
QPixmap Hair;
bool compisition = false;
protected:
void paintEvent(QPaintEvent *);
};
#endif // ANIMPREVIEW_H
*.cpp
#include "animpreview.h"
#include <QPainter>
AnimPreview::AnimPreview(QWidget *parent):QLabel(parent)
{
}
void AnimPreview::paintEvent(QPaintEvent *){
QPainter p(this);
QPixmap pic;
QPixmap hairs;
if(draw)
{
//Sesso
switch(sex)
{
case 0:
pic.load(":/Male/Base/Res/man_f.png");
break;
case 1:
pic.load(":/Male/Base/Res/woman_f.png");
break;
}
//capelli
if(sex == 1)
{
switch(hair)
{
case 1:
hairs.load(":/Female/Hair/Res/7_aqua.png");
break;
case 2:
hairs.load(":/Female/Hair/Res/5_gold.png");
break;
}
}
if(sex == 0)
{
switch (hair)
{
case 0:
break;
case 1:
hairs.load(":/Male/Hair/Res/1_aqua.png");
break;
case 2:
hairs.load(":/Male/Hair/Res/14_black.png");
break;
}
}
}
p.drawPixmap(width()/2 - offsetX,height()/2 - offsetY,pic,0,rotation,32,48);
p.drawPixmap(width()/2 - offsetX,height()/2 - offsetY,hairs,0,rotation,32,48);
p.drawRect(0,0, width()-1, height()-1);
base = pic;
Hair = hairs;
if(compisition)
{
QPixmap pix(128,192);
QPainter p(&pix);
p.drawPixmap(0,0,128,192, base);
p.drawPixmap(0,0,128,192, Hair);
p.end();
Composited = pix;
compisition = false;
}
}
void AnimPreview::Rotate(int value)
{
rotation = value;
update();
}
void AnimPreview::Create(int _sex, int _hair)
{
sex = _sex;
hair = _hair;
draw = true;
}
void AnimPreview::Composite()
{
compisition = true;
update();
}
void MainWindow::on_commandLinkButton_clicked()
{
QString file = QFileDialog::getSaveFileName(this,
tr("Save Sprite file"),
"",tr("File PNG (*.png)"));
if(!file.isEmpty())
{
ui->SpriteFront->Composite();
ui->SpriteFront->Composited.save(file,"PNG");
}
}