How to print the same header on multiple pages

[omci]

Hi;

I have to print a document of variable length and therefore have to check on several places for possible page breaks. I am using QPrinter with QPainter. That would not be a problem if I did not have to print a header and footer to every one of that pages. Is there any sane way of doing that? What would you recommend?

Thank you for your answers! Regards; Luka

[ChrisW67]

Every time you call newPage() output your header and footer and remove that space from the page height available to your other content.

[omci]

I'm afraid I don't quite understand your advice. Below is a sample code. In real code I have dozen while and for loops that may or may not run. And the header and footer expand through multiple lines using graphic, text and tables. I would like to make the code for header/footer reusable, so if I make a correction I would not have to scroll through the code and possibly miss something... I also have to print several different documents that have the same header/footer. Is it possible? And how? Thanks; Luka

QPrinter printer;
 
QPrintDialog *dialog = new QPrintDialog(&printer, this);
dialog->setWindowTitle(tr("Print Document"));
 
if (dialog->exec() == QDialog::Accepted) {
	QPainter painter;
	QString lorem = "Lorem ipsum dolor sit amet, consectetur adipiscing elit. Nunc quis augue erat.";
 
	ui->lineEdit->setText(QString::number(printer.height(), 10));
	if (! painter.begin(&printer))  { // failed to open file
		qWarning("Is the output file writable?");
		return;
	}
 
	int i = 1;
	int position = 0;
	int our_height = 0;
	while ( i <= 40 ) {
		// make text 1 pt (px?) larger
		painter.setFont(QFont("Arial", i));
 
		// get size of rectangle of text
		QRect text_size = painter.boundingRect(0, 0, printer.width(), 0, Qt::AlignJustify | Qt::TextWordWrap, QString::number(i, 10) + ") " + lorem);
		// calculate the height of so far used text
		our_height = position + text_size.height();
 
		// if our height is equal or greater than height of the page we introduce page break
		if( our_height >= printer.height() ) {
			printer.newPage();
			our_height = 0;
			position = 0;
		}
 
	/**
	* How would I make this possible?
	**/
		if ( our_height == 0 ) {
//				write_header();
//				write_footer();
//				position = position + height_of_header + height_of_footer;
		}
 
	// wrote our text
		painter.drawText(QRectF(0, position, printer.width(), text_size.height()), Qt::AlignJustify | Qt::TextWordWrap, QString::number(i, 10) + ") " + lorem);
	// set our new position
		i++;
		if (our_height == 0) {
			position = text_size.height();
		}
		else {
			position = our_height;
		}
	}
	painter.end();
}

QPrinter printer;

QPrintDialog *dialog = new QPrintDialog(&printer, this);
dialog->setWindowTitle(tr("Print Document"));

if (dialog->exec() == QDialog::Accepted) {
	QPainter painter;
	QString lorem = "Lorem ipsum dolor sit amet, consectetur adipiscing elit. Nunc quis augue erat.";

	ui->lineEdit->setText(QString::number(printer.height(), 10));
	if (! painter.begin(&printer))  { // failed to open file
		qWarning("Is the output file writable?");
		return;
	}

	int i = 1;
	int position = 0;
	int our_height = 0;
	while ( i <= 40 ) {
		// make text 1 pt (px?) larger
		painter.setFont(QFont("Arial", i));
			
		// get size of rectangle of text
		QRect text_size = painter.boundingRect(0, 0, printer.width(), 0, Qt::AlignJustify | Qt::TextWordWrap, QString::number(i, 10) + ") " + lorem);
		// calculate the height of so far used text
		our_height = position + text_size.height();

		// if our height is equal or greater than height of the page we introduce page break
		if( our_height >= printer.height() ) {
			printer.newPage();
			our_height = 0;
			position = 0;
		}
		
	/**
	* How would I make this possible?
	**/
		if ( our_height == 0 ) {
//				write_header();
//				write_footer();
//				position = position + height_of_header + height_of_footer;
		}
			
	// wrote our text
		painter.drawText(QRectF(0, position, printer.width(), text_size.height()), Qt::AlignJustify | Qt::TextWordWrap, QString::number(i, 10) + ") " + lorem);
	// set our new position
		i++;
		if (our_height == 0) {
			position = text_size.height();
		}
		else {
			position = our_height;
		}
	}
	painter.end();
}

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[ChrisW67]

Something like this:

#include <QtGui>
#include <QDebug>
 
static const QString header("This is the\nheader\ntext, but you can render anything here");
static const QString footer("This is the\nfooter\ntext");
 
int renderHeader(QPainter &painter) 
{
    painter.save();
    painter.resetTransform();
    painter.setFont(QFont("Courier New", 12));
    QRect boundingRect = painter.boundingRect(painter.window(), Qt::AlignJustify | Qt::TextWordWrap, header);
    painter.drawText(boundingRect, Qt::AlignJustify | Qt::TextWordWrap, header);
    painter.drawRect(boundingRect);
    painter.restore();
    return boundingRect.height();
}
 
int renderFooter(QPainter &painter) 
{
    painter.save();
    painter.resetTransform();
    painter.setFont(QFont("Courier New", 12));
    QRect boundingRect = painter.boundingRect(painter.window(), Qt::AlignJustify | Qt::TextWordWrap, footer);
    painter.translate(0, painter.window().height() - boundingRect.height());
    painter.drawText(boundingRect, Qt::AlignJustify | Qt::TextWordWrap, footer);
    painter.drawRect(boundingRect);
    painter.restore();
    return boundingRect.height();
}
 
 
 
int main(int argc, char *argv[])
{
    QApplication app(argc, argv);
 
 
QPrinter printer;
QPrintDialog dialog(&printer);
dialog.setWindowTitle("Print Document");
 
if (dialog.exec() == QDialog::Accepted) {
        QPainter painter;
        QString lorem = "Lorem ipsum dolor sit amet, consectetur adipiscing elit. Nunc quis augue erat.";
 
    if (painter.begin(&printer)) {
        int position = 0;
 
        // Render the first header and footer
        int headerHeight = renderHeader(painter);
        int footerHeight = renderFooter(painter);
 
        position = headerHeight;
        painter.translate(0, headerHeight); // I use the translation to avoid doing it manually
 
        for (int i = 0; i < 40; ++i) {
            painter.setFont(QFont("Arial", i));
            QRect boundingRect = painter.boundingRect(painter.window(), 
                Qt::AlignJustify | Qt::TextWordWrap, 
                QString::number(i, 10) + ") " + lorem);
 
            // if our height is equal or greater than height of the page we introduce page break
            if( position + boundingRect.height() + footerHeight > painter.window().height() ) {
                printer.newPage();
                headerHeight = renderHeader(painter);
                footerHeight = renderFooter(painter);
                position = headerHeight;
                painter.resetTransform();
                painter.translate(0, headerHeight);
            }
 
            // write our text
            painter.drawText(boundingRect, 
                Qt::AlignJustify | Qt::TextWordWrap, 
                QString::number(i, 10) + ") " + lorem);
            painter.translate(0, boundingRect.height());
            position += boundingRect.height();
        }
 
        painter.end();
    }
}
 
    return 0;
 
}

#include <QtGui>
#include <QDebug>

static const QString header("This is the\nheader\ntext, but you can render anything here");
static const QString footer("This is the\nfooter\ntext");

int renderHeader(QPainter &painter) 
{
    painter.save();
    painter.resetTransform();
    painter.setFont(QFont("Courier New", 12));
    QRect boundingRect = painter.boundingRect(painter.window(), Qt::AlignJustify | Qt::TextWordWrap, header);
    painter.drawText(boundingRect, Qt::AlignJustify | Qt::TextWordWrap, header);
    painter.drawRect(boundingRect);
    painter.restore();
    return boundingRect.height();
}

int renderFooter(QPainter &painter) 
{
    painter.save();
    painter.resetTransform();
    painter.setFont(QFont("Courier New", 12));
    QRect boundingRect = painter.boundingRect(painter.window(), Qt::AlignJustify | Qt::TextWordWrap, footer);
    painter.translate(0, painter.window().height() - boundingRect.height());
    painter.drawText(boundingRect, Qt::AlignJustify | Qt::TextWordWrap, footer);
    painter.drawRect(boundingRect);
    painter.restore();
    return boundingRect.height();
}



int main(int argc, char *argv[])
{
    QApplication app(argc, argv);


QPrinter printer;
QPrintDialog dialog(&printer);
dialog.setWindowTitle("Print Document");

if (dialog.exec() == QDialog::Accepted) {
        QPainter painter;
        QString lorem = "Lorem ipsum dolor sit amet, consectetur adipiscing elit. Nunc quis augue erat.";
    
    if (painter.begin(&printer)) {
        int position = 0;
        
        // Render the first header and footer
        int headerHeight = renderHeader(painter);
        int footerHeight = renderFooter(painter);

        position = headerHeight;
        painter.translate(0, headerHeight); // I use the translation to avoid doing it manually

        for (int i = 0; i < 40; ++i) {
            painter.setFont(QFont("Arial", i));
            QRect boundingRect = painter.boundingRect(painter.window(), 
                Qt::AlignJustify | Qt::TextWordWrap, 
                QString::number(i, 10) + ") " + lorem);

            // if our height is equal or greater than height of the page we introduce page break
            if( position + boundingRect.height() + footerHeight > painter.window().height() ) {
                printer.newPage();
                headerHeight = renderHeader(painter);
                footerHeight = renderFooter(painter);
                position = headerHeight;
                painter.resetTransform();
                painter.translate(0, headerHeight);
            }

            // write our text
            painter.drawText(boundingRect, 
                Qt::AlignJustify | Qt::TextWordWrap, 
                QString::number(i, 10) + ") " + lorem);
            painter.translate(0, boundingRect.height());
            position += boundingRect.height();
        }

        painter.end();
    }
}

    return 0;

}

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[omci]

Thank you for this demo, it is just what I needed. I read about save(), restore(), but did not know how to use them. Thank you also for showing me translate(), again it was a mystery for me. This will reduce my app for several thousand lines of code and make it useful again
Regards; Luka