how to show photo in QPrintPreviewDialog

[ARASHz4]

hi
i want to print a photo & before printing show a preview

i print a photo whit this code:

QPrinter PhotoPrint;

    QPrintDialog *PhotoPrintDialog = new QPrintDialog(&PhotoPrint,0);

    if(PhotoPrintDialog->exec() == QDialog::Accepted)
    {
        QImage Photo(ui->PhotoLable->pixmap()->toImage());
        QPainter painter(&PhotoPrint);
        painter.drawImage(QPoint(0,0),Photo);
        painter.end();
    }

how to show a preview before print?

[A Former User]

Hi! You can use QPrintPreviewDialog Class for this.

[ARASHz4]

@Wieland Hi
i know this, can show me example for photo

[A Former User]

mainwindow.h

#ifndef MAINWINDOW_H
#define MAINWINDOW_H

#include <QMainWindow>
#include <QPixmap>
#include <QPrinter>
#include <QPrintDialog>
#include <QPrintPreviewDialog>

namespace Ui {
class MainWindow;
}

class MainWindow : public QMainWindow
{
    Q_OBJECT

public:
    explicit MainWindow(QWidget *parent = 0);
    ~MainWindow();

    void printerPaint(QPrinter *printer);

private slots:
    void on_pushButton_clicked();
    void on_pushButton_2_clicked();

private:
    Ui::MainWindow *ui;
    QPixmap m_pixmap{"/home/patrick/m.png"};
    QPrinter m_printer;
    QPrintDialog m_printDialog{&m_printer};
    QPrintPreviewDialog m_printPreviewDialog{&m_printer};
};

#endif // MAINWINDOW_H

mainwindow.cpp

#include "mainwindow.h"
#include "ui_mainwindow.h"

#include <QPainter>

MainWindow::MainWindow(QWidget *parent) :
    QMainWindow(parent),
    ui(new Ui::MainWindow)
{
    ui->setupUi(this);
    ui->label->setPixmap(m_pixmap);
    connect(&m_printPreviewDialog, &QPrintPreviewDialog::paintRequested,
            this, &MainWindow::printerPaint);
}

MainWindow::~MainWindow()
{
    delete ui;
}

void MainWindow::printerPaint(QPrinter *printer)
{
    QPainter painter(printer);
    painter.drawPixmap(QPoint(0,0), m_pixmap);
}

// Print without preview
void MainWindow::on_pushButton_clicked()
{
    if (m_printDialog.exec() == QDialog::Accepted)
        printerPaint(&m_printer);
}

// Show preview, potentially print from this dialog
void MainWindow::on_pushButton_2_clicked()
{
    m_printPreviewDialog.exec();
}

[ARASHz4]

@Wieland thank but whare you tell qprintperview set a pohto for preview?

[A Former User]

When the preview dialog is executed it emits a signal and that is connected to MainWindow::printerPaint. Inside the latter function we paint the photo. The photo is stored inside m_pixmap which is initialized in the header file in this example. Printing without preview uses MainWindow::printerPaint, too, so we don't have to copy and paste the exact same code again.