Qt update TableView every x seconds - qt

Question

I have a QAbstractTableModel that has a list of custom items it displays, this TableModel is the model of a TableView. How can i refresh the TableView every x seconds? I tried beginInsertRows and endInsertRows, but this caused laggs because im editing too many items per second, so i only want to refresh it every x seconds.

Answer 1

use QTimer
for example,
QTimer *timer = new QTimer(this);
connect(timer, SIGNAL(timeout()), this, SLOT(processOneThing()));
timer->start(1000);
in processOneThing , you can write the code of refreshing data and set the timer again using timer->start(1000);

Answer 2

Using beginInsertRows and endInsertRows could potentially cause a whole lot of reorgansation internally that is not necessary. If the structure of the model (i.e. ordering, number of items,etc.) doesn't change, only the display content, you're far better off emitting the dataChanged signal.
That signal tells the connected views to refresh, and they'll only redraw the items that are visible within the viewport, they don't process items that are hidden.
#include <QtWidgets/QApplication>
#include <QtCore/qtimer.h>
#include <QtWidgets/qtableview.h>
#include <QtCore/QAbstractTableModel>
class TableModel : public QAbstractTableModel {
public:
TableModel(QObject *parent = nullptr) : QAbstractTableModel(parent) {
connect(&timer, &QTimer::timeout, [=]() {
emit dataChanged(index(0, 0), index(rowCount() - 1, columnCount() - 1));
});
timer.start(1000);
}
virtual int rowCount(QModelIndex const &index = QModelIndex()) const { return index.parent().isValid() ? 0 : 5; }
virtual int columnCount(QModelIndex const &index = QModelIndex()) const { return index.parent().isValid() ? 0 : 10; }
virtual QVariant data(QModelIndex const &index, int role = Qt::DisplayRole) const {
QVariant value;
if (index.isValid() && role == Qt::DisplayRole) {
value = QString("X %1; Y: %2").arg(qrand()).arg(qrand());
}
return value;
}
private:
QTimer timer;
};
int main(int argc, char *argv[])
{
QApplication a(argc, argv);
TableModel model;
QTableView view;
view.setModel(&model);
view.show();
return a.exec();
}