update grid of pixmap labels based on 2d char arrray value

[ChrisW67]

One approach would to use the grid layout that contains the (anonymous) widgets to allow access by row and column. This makes mapping from underlying 2D array to widget trivial. For example:

#include <QtGui>
#include <QDebug>
 
class MainWindow: public QMainWindow {
    Q_OBJECT
public:
    MainWindow(QWidget *p = 0): 
        QMainWindow(p) ,
        m_blankPixmap("blank.png"),
        m_otherPixmap("other.png")
    {
        QWidget *central = new QWidget(this);
 
        m_layout = new QGridLayout(central);
        for(int r = 0; r < 10; ++r) {
            for(int c = 0; c < 10; ++c) {
                QLabel *label = new QLabel(central);
                label->setPixmap(m_blankPixmap);
                m_layout->addWidget(label, r, c, Qt::AlignCenter);
            }
        }
 
        central->setLayout(m_layout);
        setCentralWidget(central);
 
        setCellPixmap(3, 3, m_otherPixmap);
    }
 
    void setCellPixmap(int row, int col, const QPixmap &pixmap) {
        QLabel *label = qobject_cast<QLabel*>( m_layout->itemAtPosition(row, col)->widget() );
        if (label) {
            label->setPixmap(pixmap);
        }
    }
private:
    QGridLayout *m_layout;
    const QPixmap m_blankPixmap;
    const QPixmap m_otherPixmap;
};
 
int main(int argc, char *argv[])
{
    QApplication app(argc, argv);
 
    MainWindow m;
    m.show();
    return app.exec();
}
#include "main.moc"

#include <QtGui>
#include <QDebug>

class MainWindow: public QMainWindow {
    Q_OBJECT
public:
    MainWindow(QWidget *p = 0): 
        QMainWindow(p) ,
        m_blankPixmap("blank.png"),
        m_otherPixmap("other.png")
    {
        QWidget *central = new QWidget(this);

        m_layout = new QGridLayout(central);
        for(int r = 0; r < 10; ++r) {
            for(int c = 0; c < 10; ++c) {
                QLabel *label = new QLabel(central);
                label->setPixmap(m_blankPixmap);
                m_layout->addWidget(label, r, c, Qt::AlignCenter);
            }
        }

        central->setLayout(m_layout);
        setCentralWidget(central);

        setCellPixmap(3, 3, m_otherPixmap);
    }

    void setCellPixmap(int row, int col, const QPixmap &pixmap) {
        QLabel *label = qobject_cast<QLabel*>( m_layout->itemAtPosition(row, col)->widget() );
        if (label) {
            label->setPixmap(pixmap);
        }
    }
private:
    QGridLayout *m_layout;
    const QPixmap m_blankPixmap;
    const QPixmap m_otherPixmap;
};

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

    MainWindow m;
    m.show();
    return app.exec();
}
#include "main.moc"

To copy to clipboard, switch view to plain text mode