"QComboBox Pop-up" expanding and QtWebkit - c++

In Firefox/Chrome/InternetExplorer/Safari/Opera pop-ups from the combobox expand as the content, see Firefox picture:
QComboBox pop-up does not expand the content. Pop-ups are limited by the size of QComboBox, see QWebView picture:
So I implemented the QComboBox::showPopup:
void newQComboBox::showPopup() {
int width = this->width();
this->view()->setTextElideMode( Qt::ElideNone );
const int iconSize = this->iconSize().width();
const QFontMetrics fontMetrics = this->fontMetrics();
const int j = this->count();
for( int i=0; i < j; ++i ) {
const int textWidth = fontMetrics.width( this->itemText(i) + "WWW" );
if (this->itemIcon(i).isNull()) {
width = qMax(width, textWidth);
} else {
width = qMax(width, textWidth + iconSize);
}
}
QStyleOptionComboBox opt;
this->initStyleOption(&opt);
QSize size(width, 0);
size = this->style()->sizeFromContents(QStyle::CT_ComboBox, &opt, size, this);
this->view()->setFixedWidth( width );
QComboBox::showPopup();
}
Is there any way to modify (reimplement) the QComboBox::showPopup of QWebViews (QtWebkit)?
Qt-BUG (suggestion): https://bugreports.qt.io/browse/QTBUG-35771


I solved using QProxyStyle class, example:
#include <QProxyStyle>
#include <QAbstractItemView>
#include <QComboBox>
class myProxyStyle : public QProxyStyle
{
public:
int styleHint(StyleHint hint, const QStyleOption *option, const QWidget *widget, QStyleHintReturn *returnData) const
{
if(hint == QStyle::SH_ComboBox_Popup) {
const QComboBox *combo = (QComboBox *) widget;//cast to QComboBox
const QObjectList a = combo->children();
const int j = a.count();
QAbstractItemView *view = 0;
QString className = "";
bool hasView = false;
/*
at this point I have not used combo->view() because he "crash" the application without explanation
so I had to make a loop to find the "view"
*/
for (int i = 0; i < j; ++i) {
const QObjectList b = a.at(i)->children();
const int y = b.count();
for (int x = 0; x < y; ++x) {
className = b.at(x)->metaObject()->className();
if (className == "QComboBoxListView") {
view = (QAbstractItemView *) b.at(x);
hasView = true;
break;
}
}
if (hasView) {
break;
}
}
if (hasView) {
const int iconSize = combo->iconSize().width();
const QFontMetrics fontMetrics1 = view->fontMetrics();
const QFontMetrics fontMetrics2 = combo->fontMetrics();
const int j = combo->count();
int width = combo->width(); //default width
for (int i = 0; i < j; ++i) {
const int textWidth = qMax(
fontMetrics1.width(combo->itemText(i) + "WW"),
fontMetrics2.width(combo->itemText(i) + "WW")
);
if(combo->itemIcon(i).isNull()) {
width = qMax(width, textWidth);
} else {
width = qMax(width, textWidth + iconSize);
}
}
view->setFixedWidth(width);
}
}
return QProxyStyle::styleHint(hint, option, widget, returnData);
}
};
how to use:
You must apply in QApplication (usually file main.cpp):
int main(int argc, char *argv[])
{
QApplication a(argc, argv);
a.setStyle(new myProxyStyle);//set ProxyStyle
return a.exec();
}
#peppe thanks to your comment I got the solution


Please try to make use of the setMinimumWidth function and pass the max width you have calculated. it should work
ui.comboBox->view()->setMinimumWidth(width);
for more detail please go through https://qt-project.org/forums/viewthread/26388 link

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i edited the opengl series example given by the qt as per my needs.
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//***********datasource.h**********//
#ifndef DATASOURCE_H
#define DATASOURCE_H
#include <QtCore/QObject>
#include <QtCharts/QXYSeries>
#include <QtWidgets/QLabel>
#include <QtCore/QElapsedTimer>
#include <QtCore/QTimer>
QT_CHARTS_USE_NAMESPACE
class DataSource : public QObject
{
Q_OBJECT
public:
explicit DataSource(QObject *parent = 0);
void startUpdates(const QList<QXYSeries *> &seriesList, QLabel *fpsLabel);
public slots:
void generateData(int seriesCount, int rowCount, int colCount);
void update(QAbstractSeries *series, int seriesIndex);
void handleSceneChanged();
void updateAllSeries();
private:
QVector<QVector<QVector<QPointF> > > m_data;
int m_index;
QList<QXYSeries *> m_seriesList;
QLabel *m_fpsLabel;
QElapsedTimer m_fpsTimer;
QTimer m_dataUpdater;
};
#endif // DATASOURCE_H
//*************datasource.cpp*******************//
#include "datasource.h"
#include <QtCore/QtMath>
#include<QDebug>
QT_CHARTS_USE_NAMESPACE
int shift=0;
int c[2048]={50,149,143,148,151,151,150,150,149,149,152,148,148,147,146,152,149,150,147,151,150,149,148,149,152,150,148,150,147,149,149,149,149,151,152,151,149,148,151,147,151,147,150,147,151,150,154,150,151,151,151,151,154,154,150,152,148,151,150,148,150,151,149,151,150,156,155,159,158,154,154,151,152,154,155,150,154,149,150,149,154,152,155,150,154,152,155,150,149,154,150,156,154,150,151,150,151,155,151,157,151,152,150,151,148,150,150,157,150,156,150,147,155,150,155,155,152,150,154,151,152,151,150,152,151,157,151,152,150,149,154,152,154,154,151,151,150,150,157,154,154,155,150,155,157,150,152,151,156,151,150,152,152,154,155,150,155,150,150,156,154,149,152,154,154,154,151,150,156,148,150,157,150,154,150,154,154,154,156,150,150,155,156,155,156,154,154,150,154,155,158,151,154,154,150,150,156,151,148,150,151,150,154,150,156,150,154,151,154,150,150,157,154,155,154,157,155,156,152,155,155,157,154,159,156,156,154,155,154,156,156,151,152,150,150,156,154,152,159,150,150,158,150,155,156,155,156,155,155,154,154,154,155,155,155,154,149,156,150,156,150,155,155,156,157,150,157,157,151,157,157,158,152,150,156,155,154,154,155,156,154,154,156,150,157,154,150,157,157,152,155,155,154,154,155,154,156,156,150,155,154,157,155,156,156,150,155,157,154,157,154,161,155,155,155,158,156,156,150,154,155,155,157,157,157,152,155,156,159,155,154,154,155,157,151,159,154,157,154,157,158,154,155,155,155,159,155,156,156,157,154,158,155,160,157,157,158,158,155,158,155,155,155,150,159,156,157,158,156,157,156,154,156,158,157,156,159,156,157,158,155,157,154,157,155,157,156,157,157,159,156,157,156,162,158,155,159,156,156,159,155,157,155,158,155,162,156,157,154,163,157,158,156,161,157,156,157,156,154,158,159,160,156,159,159,157,159,155,162,159,156,155,157,154,155,156,157,156,157,155,159,157,160,150,157,158,152,157,155,154,158,155,158,158,158,155,158,156,156,157,159,156,159,156,157,157,156,156,158,155,155,160,150,158,154,159,157,154,157,155,157,159,154,157,150,155,155,155,152,155,159,158,155,155,158,156,154,154,155,157,157,154,158,155,159,155,160,156,159,157,155,150,160,156,150,154,157,150,158,155,150,154,157,155,158,160,158,154,159,157,157,157,155,156,159,154,157,160,154,155,157,156,150,156,157,156,158,150,156,156,154,157,156,159,158,158,156,155,156,155,156,155,160,155,156,158,157,154,150,158,157,155,157,155,158,156,159,156,157,159,157,156,157,159,154,160,158,158,160,156,155,154,161,159,160,157,156,154,155,154,156,159,158,155,154,150,158,162,156,156,155,154,160,159,162,160,159,158,161,150,159,156,155,160,158,159,158,155,161,155,157,154,154,156,150,156,163,154,149,160,160,155,159,155,156,155,150,157,158,157,157,154,157,155,158,155,156,156,156,155,150,156,157,155,155,155,157,157,157,157,155,157,157,155,159,158,150,156,157,155,158,156,158,155,154,157,157,156,155,156,155,160,157,159,150,158,155,162,157,159,159,155,156,154,155,158,157,161,156,158,157,155,156,158,158,157,156,158,157,154,155,150,158,156,160,160,160,156,157,154,155,150,159,156,152,156,160,158,157,154,158,158,158,155,156,160,160,155,156,157,158,157,159,157,161,155,152,157,158,154,157,160,156,158,155,158,158,156,155,155,150,154,156,155,158,155,155,157,156,158,154,155,158,162,156,159,158,157,159,154,155,160,157,158,154,155,157,158,159,158,158,157,155,156,159,159,155,155,158,155,155,158,155,160,161,157,159,159,156,155,150,156,155,150,156,157,155,155,158,155,156,159,156,158,162,155,160,154,158,158,158,157,160,156,155,157,152,156,160,158,160,155,158,155,155,157,155,156,159,154,155,157,157,160,159,156,157,162,158,156,157,154,160,157,156,159,159,156,155,159,158,157,156,162,160,158,157,162,157,158,157,157,163,156,156,160,161,154,155,156,159,157,156,158,159,157,155,157,162,157,160,158,159,155,156,155,160,158,157,155,160,159,156,157,157,160,155,157,158,157,157,156,160,155,157,156,157,159,159,160,159,160,157,162,157,157,154,157,157,159,161,155,160,155,155,157,160,156,158,158,161,159,156,156,158,160,160,158,155,157,161,154,160,156,155,156,160,158,156,157,150,155,154,160,157,154,155,155,160,155,154,158,157,155,160,155,156,160,154,157,154,158,157,159,157,155,152,155,156,156,155,155,155,155,156,156,159,159,157,160,155,158,158,157,157,150,155,156,155,156,156,155,159,150,161,155,159,156,156,158,161,155,157,156,159,155,150,155,156,161,155,156,156,154,157,155,157,158,156,158,160,155,161,158,156,159,157,156,159,155,158,162,155,160,158,161,160,156,158,164,156,158,159,158,154,161,158,157,157,156,156,160,157,155,156,160,160,155,158,156,162,160,160,158,157,160,163,156,154,154,162,156,157,155,160,150,158,155,156,154,157,159,160,158,157,162,154,158,163,158,154,158,154,156,155,158,156,159,158,156,156,159,154,159,154,159,156,157,157,160,159,159,156,150,159,158,156,156,156,158,155,158,156,155,156,157,158,156,156,159,157,157,156,156,159,157,160,159,161,159,158,158,160,157,158,156,156,160,160,158,157,157,158,162,150,156,158,158,163,159,158,154,156,159,159,159,157,158,155,161,155,159,155,160,157,156,161,158,157,156,157,158,155,160,158,160,156,157,159,160,156,156,158,156,156,156,155,157,156,156,160,157,154,159,160,157,158,162,159,158,161,158,156,160,156,159,162,162,157,158,160,159,158,160,160,157,156,159,158,160,157,161,158,158,154,160,160,161,154,161,159,156,158,157,160,159,161,157,157,162,156,157,159,152,161,157,158,158,157,158,157,158,158,157,159,159,159,150,157,159,158,151,158,156,160,158,158,157,156,158,158,156,156,158,160,155,159,156,161,156,163,154,161,159,157,159,161,158,157,155,159,156,158,155,161,158,156,161,155,159,158,159,155,162,154,162,161,157,159,159,156,160,157,159,160,160,159,156,156,156,157,157,163,159,161,156,158,156,159,156,157,158,156,160,163,163,156,160,159,157,156,160,160,155,157,155,160,157,160,160,157,158,159,157,159,160,161,160,159,156,158,157,157,156,160,156,162,159,157,154,156,155,162,159,159,161,157,162,159,156,156,156,162,158,161,158,167,159,159,156,158,156,159,157,154,159,160,159,155,163,158,158,162,156,162,158,158,156,161,159,155,160,155,159,150,161,155,156,157,157,155,157,155,163,155,158,157,155,157,161,154,154,155,156,157,159,156,156,159,158,158,158,161,159,156,158,158,158,160,160,162,158,159,156,161,154,154,158,157,161,159,157,159,154,159,161,159,159,160,159,162,160,158,158,157,160,159,161,161,157,158,157,158,162,160,161,159,161,159,162,159,157,161,160,158,160,160,156,157,157,159,159,159,161,158,160,155,157,162,159,162,161,159,161,158,159,162,155,159,161,155,160,157,156,157,160,154,157,159,157,158,160,159,160,157,156,156,158,157,158,154,161,159,154,158,159,160,160,159,162,159,161,158,161,158,156,160,160,158,156,159,158,155,155,156,160,159,162,158,160,159,159,159,156,156,156,164,155,158,157,160,157,160,158,160,158,158,159,152,159,158,157,162,160,160,160,159,155,158,154,159,161,157,160,158,157,154,160,155,158,160,152,156,150,158,157,159,158,162,158,157,157,156,160,159,158,159,155,156,160,154,158,155,156,152,156,156,156,156,154,158,156,157,155,154,156,156,157,156,158,157,156,159,161,152,156,155,152,156,156,155,158,159,157,156,157,156,158,158,155,152,161,159,155,156,157,152,156,158,158,150,155,152,158,159,158,155,160,150,154,156,158,155,157,160,156,157,155,155,157,159,158,156,158,158,156,159,156,157,150,155,158,158,157,158,159,158,150,160,156,157,158,155,154,157,156,156,160,157,161,157,158,158,158,150,150,154,150,150,150,157,157,150,158,155,159,158,158,150,158,159,154,154,157,154,155,157,155,154,155,157,154,157,156,157,158,160,155,159,155,157,160,150,152,156,156,156,154,157,156,154,156,159,154,155,150,150,158,158,156,160,158,152,150,157,154,159,150,150,158,155,154,157,155,154,150,152,156,156,154,159,152,156,156,150,156,156,157,154,152,154,151,155,155,152,158,157,161,152,152,157,154,158,150,156,158,150,157,154,156,154,155,158,156,154,150,154,158,150,159,155,151,152,155,154,154,154,154,152,150,154,154,154,152,150,150,156,150,157,150,151,151,151,155,150,150,158,150,152,155,155,152,150,156,151,152,150,151,158,150,152,152,158,148,154,151,152,154,155,150,154,154,154,155,155,150,150,156,151,155,151,151,151,152,152,150,151,151,151,151,150,156,152,159,148,156,154,150,149,156,152,154,155,150,152,155,151,155,149,150,150,151,155,149,155,150,152,152,149,150,154,151,149,156,154,149,154,151,147,149,150,149,151,154,149,155,151,149,148,150,155,150,149,149,152,148,154,150,149,150,149,151,154,149,152,154,150,150,151,152,155,150,150,151,149,148,152,149};
int b[2048]={150,149,143,148,151,151,150,150,149,149,152,148,148,147,146,152,149,150,147,151,150,149,148,149,152,150,148,150,147,149,149,149,149,151,152,151,149,148,151,147,151,147,150,147,151,153,154,153,151,151,151,151,154,154,153,152,148,151,150,148,153,151,149,151,150,156,155,159,158,154,154,151,152,154,155,150,154,149,153,149,154,152,155,150,154,152,155,150,149,154,150,156,154,153,151,153,151,155,151,157,151,152,153,151,148,153,150,157,150,156,153,147,155,150,155,155,152,153,154,151,152,151,153,152,151,157,151,152,153,149,154,152,154,154,151,151,153,153,157,154,154,155,153,155,157,153,152,151,156,151,153,152,152,154,155,153,155,150,150,156,154,149,152,154,154,154,151,150,156,148,150,157,153,154,153,154,154,154,156,150,150,155,156,155,156,154,154,153,154,155,158,151,154,154,153,153,156,151,148,153,151,153,154,153,156,153,154,151,154,153,153,157,154,155,154,157,155,156,152,155,155,157,154,159,156,156,154,155,154,156,156,151,152,153,153,156,154,152,159,150,153,158,153,155,156,155,156,155,155,154,154,154,155,155,155,154,149,156,153,156,153,155,155,156,157,150,157,157,151,157,157,158,152,153,156,155,154,154,155,156,154,154,156,153,157,154,150,157,157,152,155,155,154,154,155,154,156,156,153,155,154,157,155,156,156,153,155,157,154,157,154,161,155,155,155,158,156,156,153,154,155,155,157,157,157,152,155,156,159,155,154,154,155,157,151,159,154,157,154,157,158,154,155,155,155,159,155,156,156,157,154,158,155,160,157,157,158,158,155,158,155,155,155,153,159,156,157,158,156,157,156,154,156,158,157,156,159,156,157,158,155,157,154,157,155,157,156,157,157,159,156,157,156,162,158,155,159,156,156,159,155,157,155,158,155,162,156,157,154,163,157,158,156,161,157,156,157,156,154,158,159,160,156,159,159,157,159,155,162,159,156,155,157,154,155,156,157,156,157,155,159,157,160,153,157,158,152,157,155,154,158,155,158,158,158,155,158,156,156,157,159,156,159,156,157,157,156,156,158,155,155,160,153,158,154,159,157,154,157,155,157,159,154,157,153,155,155,155,152,155,159,158,155,155,158,156,154,154,155,157,157,154,158,155,159,155,160,156,159,157,155,153,160,156,150,154,157,153,158,155,153,154,157,155,158,160,158,154,159,157,157,157,155,156,159,154,157,160,154,155,157,156,153,156,157,156,158,153,156,156,154,157,156,159,158,158,156,155,156,155,156,155,160,155,156,158,157,154,153,158,157,155,157,155,158,156,159,156,157,159,157,156,157,159,154,160,158,158,160,156,155,154,161,159,160,157,156,154,155,154,156,159,158,155,154,153,158,162,156,156,155,154,160,159,162,160,159,158,161,153,159,156,155,160,158,159,158,155,161,155,157,154,154,156,153,156,163,154,149,160,160,155,159,155,156,155,153,157,158,157,157,154,157,155,158,155,156,156,156,155,153,156,157,155,155,155,157,157,157,157,155,157,157,155,159,158,153,156,157,155,158,156,158,155,154,157,157,156,155,156,155,160,157,159,153,158,155,162,157,159,159,155,156,154,155,158,157,161,156,158,157,155,156,158,158,157,156,158,157,154,155,153,158,156,160,160,160,156,157,154,155,153,159,156,152,156,160,158,157,154,158,158,158,155,156,160,160,155,156,157,158,157,159,157,161,155,152,157,158,154,157,160,156,158,155,158,158,156,155,155,153,154,156,155,158,155,155,157,156,158,154,155,158,162,156,159,158,157,159,154,155,160,157,158,154,155,157,158,159,158,158,157,155,156,159,159,155,155,158,155,155,158,155,160,161,157,159,159,156,155,153,156,155,153,156,157,155,155,158,155,156,159,156,158,162,155,160,154,158,158,158,157,160,156,155,157,152,156,160,158,160,155,158,155,155,157,155,156,159,154,155,157,157,160,159,156,157,162,158,156,157,154,160,157,156,159,159,156,155,159,158,157,156,162,160,158,157,162,157,158,157,157,163,156,156,160,161,154,155,156,159,157,156,158,159,157,155,157,162,157,160,158,159,155,156,155,160,158,157,155,160,159,156,157,157,160,155,157,158,157,157,156,160,155,157,156,157,159,159,160,159,160,157,162,157,157,154,157,157,159,161,155,160,155,155,157,160,156,158,158,161,159,156,156,158,160,160,158,155,157,161,154,160,156,155,156,160,158,156,157,153,155,154,160,157,154,155,155,160,155,154,158,157,155,160,155,156,160,154,157,154,158,157,159,157,155,152,155,156,156,155,155,155,155,156,156,159,159,157,160,155,158,158,157,157,153,155,156,155,156,156,155,159,153,161,155,159,156,156,158,161,155,157,156,159,155,153,155,156,161,155,156,156,154,157,155,157,158,156,158,160,155,161,158,156,159,157,156,159,155,158,162,155,160,158,161,160,156,158,164,156,158,159,158,154,161,158,157,157,156,156,160,157,155,156,160,160,155,158,156,162,160,160,158,157,160,163,156,154,154,162,156,157,155,160,153,158,155,156,154,157,159,160,158,157,162,154,158,163,158,154,158,154,156,155,158,156,159,158,156,156,159,154,159,154,159,156,157,157,160,159,159,156,153,159,158,156,156,156,158,155,158,156,155,156,157,158,156,156,159,157,157,156,156,159,157,160,159,161,159,158,158,160,157,158,156,156,160,160,158,157,157,158,162,153,156,158,158,163,159,158,154,156,159,159,159,157,158,155,161,155,159,155,160,157,156,161,158,157,156,157,158,155,160,158,160,156,157,159,160,156,156,158,156,156,156,155,157,156,156,160,157,154,159,160,157,158,162,159,158,161,158,156,160,156,159,162,162,157,158,160,159,158,160,160,157,156,159,158,160,157,161,158,158,154,160,160,161,154,161,159,156,158,157,160,159,161,157,157,162,156,157,159,152,161,157,158,158,157,158,157,158,158,157,159,159,159,153,157,159,158,151,158,156,160,158,158,157,156,158,158,156,156,158,160,155,159,156,161,156,163,154,161,159,157,159,161,158,157,155,159,156,158,155,161,158,156,161,155,159,158,159,155,162,154,162,161,157,159,159,156,160,157,159,160,160,159,156,156,156,157,157,163,159,161,156,158,156,159,156,157,158,156,160,163,163,156,160,159,157,156,160,160,155,157,155,160,157,160,160,157,158,159,157,159,160,161,160,159,156,158,157,157,156,160,156,162,159,157,154,156,155,162,159,159,161,157,162,159,156,156,156,162,158,161,158,167,159,159,156,158,156,159,157,154,159,160,159,155,163,158,158,162,156,162,158,158,156,161,159,155,160,155,159,153,161,155,156,157,157,155,157,155,163,155,158,157,155,157,161,154,154,155,156,157,159,156,156,159,158,158,158,161,159,156,158,158,158,160,160,162,158,159,156,161,154,154,158,157,161,159,157,159,154,159,161,159,159,160,159,162,160,158,158,157,160,159,161,161,157,158,157,158,162,160,161,159,161,159,162,159,157,161,160,158,160,160,156,157,157,159,159,159,161,158,160,155,157,162,159,162,161,159,161,158,159,162,155,159,161,155,160,157,156,157,160,154,157,159,157,158,160,159,160,157,156,156,158,157,158,154,161,159,154,158,159,160,160,159,162,159,161,158,161,158,156,160,160,158,156,159,158,155,155,156,160,159,162,158,160,159,159,159,156,156,156,164,155,158,157,160,157,160,158,160,158,158,159,152,159,158,157,162,160,160,160,159,155,158,154,159,161,157,160,158,157,154,160,155,158,160,152,156,153,158,157,159,158,162,158,157,157,156,160,159,158,159,155,156,160,154,158,155,156,152,156,156,156,156,154,158,156,157,155,154,156,156,157,156,158,157,156,159,161,152,156,155,152,156,156,155,158,159,157,156,157,156,158,158,155,152,161,159,155,156,157,152,156,158,158,150,155,152,158,159,158,155,160,150,154,156,158,155,157,160,156,157,155,155,157,159,158,156,158,158,156,159,156,157,153,155,158,158,157,158,159,158,153,160,156,157,158,155,154,157,156,156,160,157,161,157,158,158,158,153,153,154,153,153,153,157,157,150,158,155,159,158,158,153,158,159,154,154,157,154,155,157,155,154,155,157,154,157,156,157,158,160,155,159,155,157,160,153,152,156,156,156,154,157,156,154,156,159,154,155,153,153,158,158,156,160,158,152,153,157,154,159,153,153,158,155,154,157,155,154,153,152,156,156,154,159,152,156,156,153,156,156,157,154,152,154,151,155,155,152,158,157,161,152,152,157,154,158,153,156,158,153,157,154,156,154,155,158,156,154,153,154,158,153,159,155,151,152,155,154,154,154,154,152,153,154,154,154,152,153,153,156,153,157,153,151,151,151,155,153,153,158,153,152,155,155,152,153,156,151,152,153,151,158,153,152,152,158,148,154,151,152,154,155,153,154,154,154,155,155,153,153,156,151,155,151,151,151,152,152,150,151,151,151,151,150,156,152,159,148,156,154,150,149,156,152,154,155,153,152,155,151,155,149,153,150,151,155,149,155,153,152,152,149,153,154,151,149,156,154,149,154,151,147,149,153,149,151,154,149,155,151,149,148,150,155,150,149,149,152,148,154,153,149,150,149,151,154,149,152,154,153,150,151,152,155,153,150,151,149,148,152,149 };
DataSource::DataSource(QObject *parent) :
QObject(parent),
m_index(-1)
{
generateData(0, 0, 0);
}
void DataSource::update(QAbstractSeries *series, int seriesIndex)
{
if (series) {
QXYSeries *xySeries = static_cast<QXYSeries *>(series);
const QVector<QVector<QPointF> > &seriesData = m_data.at(seriesIndex);
if (seriesIndex == 0)
m_index++;
if (m_index > seriesData.count() - 1)
m_index = 0;
QVector<QPointF> points = seriesData.at(m_index);
// Use replace instead of clear + append, it's optimized for performance
xySeries->replace(points);
}
}
void DataSource::handleSceneChanged()
{
m_dataUpdater.start();
}
void DataSource::updateAllSeries()
{
static int frameCount = 0;
static QString labelText = QStringLiteral("FPS: %1");
for (int i = 0; i < m_seriesList.size(); i++)
update(m_seriesList[i], i);
frameCount++;
int elapsed = m_fpsTimer.elapsed();
if (elapsed >= 1000) {
elapsed = m_fpsTimer.restart();
qreal fps = qreal(0.1 * int(10000.0 * (qreal(frameCount) / qreal(elapsed))));
m_fpsLabel->setText(labelText.arg(QString::number(fps, 'f', 1)));
m_fpsLabel->adjustSize();
frameCount = 0;
}
m_data.clear();
// Append the new data depending on the type
QVector<QVector<QPointF> > seriesData;
QVector<QPointF> points;
// points.reserve(2048);
for (int j(0); j < 2048; j++) {
qreal x(0);
qreal y(0);
if(shift==0)
{
y = b[j] ;
x=j;
}else
{
y = c[j] ;
x=j;
}
points.append(QPointF(x, y));
}
seriesData.append(points);
m_data.append(seriesData);
if(shift==0)
{
shift=1;
}else
{
shift=0;
}
}
void DataSource::startUpdates(const QList<QXYSeries *> &seriesList, QLabel *fpsLabel)
{
m_seriesList = seriesList;
m_fpsLabel = fpsLabel;
m_dataUpdater.setInterval(500);
m_dataUpdater.setSingleShot(true);
QObject::connect(&m_dataUpdater, &QTimer::timeout,this, &DataSource::updateAllSeries);
m_fpsTimer.start();
updateAllSeries();
}
void DataSource::generateData(int seriesCount, int rowCount, int colCount)
{
// Remove previous data
foreach (QVector<QVector<QPointF> > seriesData, m_data) {
foreach (QVector<QPointF> row, seriesData)
row.clear();
}
m_data.clear();
// Append the new data depending on the type
for (int k(0); k < seriesCount; k++) {
QVector<QVector<QPointF> > seriesData;
for (int i(0); i < rowCount; i++) {
QVector<QPointF> points;
points.reserve(colCount);
for (int j(0); j < colCount; j++) {
qreal x(0);
qreal y(0);
if(shift==0)
{
y = a[j] ;
x=j;
}else
{
y = b[j] ;
x=j;
}
points.append(QPointF(x, y));
}
seriesData.append(points);
}
m_data.append(seriesData);
}
if(shift==0)
{
shift=1;
}else
{
shift=0;
}
qDebug()<<"test";
}
//***********main.cpp**********//
#include "datasource.h"
#include <QtWidgets/QApplication>
#include <QtWidgets/QMainWindow>
#include <QtCharts/QChartView>
#include <QtCharts/QLineSeries>
#include <QtCharts/QScatterSeries>
#include <QtCharts/QValueAxis>
#include <QtCharts/QLogValueAxis>
#include <QtWidgets/QLabel>
QT_CHARTS_USE_NAMESPACE
int main(int argc, char *argv[])
{
QApplication a(argc, argv);
QStringList colors;
colors << "red" << "blue" << "green" << "black";
QChart *chart = new QChart();
chart->legend()->hide();
QValueAxis *axisX = new QValueAxis;
QValueAxis *axisY = new QValueAxis;
chart->addAxis(axisX, Qt::AlignBottom);
chart->addAxis(axisY, Qt::AlignLeft);
const int seriesCount = 1;
const int pointCount = 2048;
chart->setTitle("OpenGL Accelerated Series");
QList<QXYSeries *> seriesList;
for (int i = 0; i < seriesCount; i++) {
QXYSeries *series = 0;
int colorIndex = i % colors.size();
if (i % 2) {
series = new QScatterSeries;
QScatterSeries *scatter = static_cast<QScatterSeries *>(series);
scatter->setColor(QColor(colors.at(colorIndex)));
scatter->setMarkerSize(qreal(colorIndex + 2) / 2.0);
// Scatter pen doesn't have affect in OpenGL drawing, but if you disable OpenGL drawing
// this makes the marker border visible and gives comparable marker size to OpenGL
// scatter points.
scatter->setPen(QPen("black"));
} else {
series = new QLineSeries;
series->setPen(QPen(QBrush(QColor(colors.at(colorIndex))),
qreal(colorIndex + 2) / 2.0));
}
seriesList.append(series);
//![1]
series->setUseOpenGL(true);
//![1]
chart->addSeries(series);
series->attachAxis(axisX);
series->attachAxis(axisY);
}
if (axisX->type() == QAbstractAxis::AxisTypeLogValue)
axisX->setRange(0.1, 2048.0);
else
axisX->setRange(0, 2048.0);
if (axisY->type() == QAbstractAxis::AxisTypeLogValue)
axisY->setRange(0.1, 255.0);
else
axisY->setRange(0, 255.0);
QChartView *chartView = new QChartView(chart);
QMainWindow window;
window.setCentralWidget(chartView);
window.resize(600, 400);
window.show();
DataSource dataSource;
dataSource.generateData(seriesCount, 1, pointCount);
QLabel *fpsLabel = new QLabel(&window);
QLabel *countLabel = new QLabel(&window);
QString countText = QStringLiteral("Total point count: %1");
countLabel->setText(countText.arg(pointCount * seriesCount));
countLabel->adjustSize();
fpsLabel->move(10, 2);
fpsLabel->adjustSize();
fpsLabel->raise();
fpsLabel->show();
countLabel->move(10, fpsLabel->height());
fpsLabel->raise();
countLabel->show();
// We can get more than one changed event per frame, so do async update.
// This also allows the application to be responsive.
QObject::connect(chart->scene(), &QGraphicsScene::changed,
&dataSource, &DataSource::handleSceneChanged);
dataSource.startUpdates(seriesList, fpsLabel);
return a.exec();
}

Why does the platform created with for cycle go over the border limit?

I've started programming just recently and I've learned the basic concepts of classes and objects and how to create them. So I decided to try and create a simple game of breakout with what I've learned so far. I've only created the main movable platform with a for cycle and make it move horizontally with the directional keys so far. I've also created a void so the platform doesn't go over the border of the screen but it doesn't work and I've tried all I could think of. Can someone please tell me what I'm doing wrong?
Game::Game( MainWindow& wnd )
:
wnd( wnd ),
gfx( wnd )
{
}
void Game::Go()
{
gfx.BeginFrame();
UpdateModel();
ComposeFrame();
gfx.EndFrame();
}
void Game::UpdateModel()
{
if (wnd.kbd.KeyIsPressed(VK_RIGHT))
{
platform.vx += 3;
}
if (wnd.kbd.KeyIsPressed(VK_LEFT))
{
platform.vx -= 3;
}
platform.ScreenLimit();
}
void Game::ComposeFrame()
{
for (platform.x = 460; platform.x <= platform.w; platform.x++)
{
for (platform.y = 500; platform.y <= platform.h; platform.y++)
{
gfx.PutPixel(platform.x + platform.vx, platform.y, 255, 255, 255);
}
}
}
and here's the header file and source file of the class I created for the platform:
Platform.h
#pragma once
#include "Graphics.h"
class Platform
{
public:
int x = 460;
int y = 500;
int vx = 0;
int width = 60;
int heigth = 10;
int w = x + width;
int h = y + heigth;
void ScreenLimit();
private:
};
Platform.cpp
#include "Platform.h"
void Platform::ScreenLimit()
{
const int left_base = x;
const int right_base = w;
if (right_base >= Graphics::ScreenWidth)
{
x = (Graphics::ScreenWidth - 6) - width;
}
else if (left_base <= 0)
{
x = 0;
}
}

How can I place Hex Data into a QT List Widget [duplicate]

Recently I am writing a debugger for my own hardware. I want to add a memory viewer widget like the eclipse or qt creator or other IDE. However, I have no idea what kind of widget to use. For example, tableWidget, is there some setting to make it like this:

The best option is to create a custom widget because the task is private and none of the widgets are accommodated to the task.
For this we will inherit from QAbstractScrollArea, from this class inherit QTableView, QListView, QListWidget and QTableWidget. It is designed to display data within a QScrollArea.
In addition documentation of this class tells us how to create a custom class.
When inheriting QAbstractScrollArea, you need to do the following:
Control the scroll bars by setting their range, value, page step, and
tracking their movements.
Draw the contents of the area in the
viewport according to the values of the scroll bars.
Handle events
received by the viewport in viewportEvent()
notably resize events.
Use viewport->update() to update the contents of the viewport instead
of update() as all painting operations take place on the viewport.
Taking that reference I created the following widget:
memoryviewer.h
#ifndef MEMORYVIEWER_H
#define MEMORYVIEWER_H
#include <QAbstractScrollArea>
#include <QBuffer>
class MemoryViewer : public QAbstractScrollArea
{
Q_OBJECT
public:
MemoryViewer(QWidget *parent = 0);
~MemoryViewer();
void setData(const QByteArray &ba);
bool setData(QIODevice &device);
protected:
void paintEvent(QPaintEvent *);
void resizeEvent(QResizeEvent *);
private:
void adjustContent();
void init();
int addressWidth();
int hexWidth();
int asciiWidth();
QByteArray data(qint64 pos=0, qint64 count=-1);
int nBlockAddress;
int mBytesPerLine;
int pxWidth;
int pxHeight;
qint64 startPos;
qint64 endPos;
int nRowsVisible;
QBuffer buffer;
QIODevice *ioDevice;
qint64 size;
QByteArray dataVisible;
QByteArray dataHex;
};
#endif // MEMORYVIEWER_H
memoryviewer.cpp
#include "memoryviewer.h"
#include <QPainter>
#include <QScrollBar>
MemoryViewer::MemoryViewer(QWidget *parent):QAbstractScrollArea(parent)
{
ioDevice = new QBuffer(this);
init();
connect(verticalScrollBar(), &QScrollBar::valueChanged, this, &MemoryViewer::adjustContent);
connect(horizontalScrollBar(), &QScrollBar::valueChanged, this, &MemoryViewer::adjustContent);
}
MemoryViewer::~MemoryViewer()
{
}
void MemoryViewer::init()
{
nBlockAddress = 2;
mBytesPerLine = 16;
pxWidth = fontMetrics().width(QChar('0'));
pxHeight = fontMetrics().height();
}
int MemoryViewer::addressWidth()
{
return (nBlockAddress*4+ nBlockAddress -1)*pxWidth;
}
int MemoryViewer::hexWidth()
{
return (mBytesPerLine*3+1)*pxWidth;
}
int MemoryViewer::asciiWidth()
{
return (mBytesPerLine*2 +1)*pxWidth;
}
QByteArray MemoryViewer::data(qint64 pos, qint64 count)
{
QByteArray buffer;
if (pos >= size)
return buffer;
if (count < 0)
count = size;
else
if ((pos + count) > size)
count = size - pos;
if(ioDevice->open(QIODevice::ReadOnly)){
ioDevice->seek(pos);
buffer = ioDevice->read(count);
ioDevice->close();
}
return buffer;
}
void MemoryViewer::setData(const QByteArray &ba)
{
buffer.setData(ba);
setData(buffer);
}
bool MemoryViewer::setData(QIODevice &device)
{
ioDevice = &device;
bool ok = ioDevice->open(QIODevice::ReadOnly);
if(ok){
size = ioDevice->size();
ioDevice->close();
}
else{
QBuffer *buf = new QBuffer(this);
ioDevice = buf;
}
init();
adjustContent();
return ok;
}
void MemoryViewer::resizeEvent(QResizeEvent *)
{
adjustContent();
}
void MemoryViewer::paintEvent(QPaintEvent *)
{
QPainter painter(viewport());
int offsetX = horizontalScrollBar()->value();
int y = pxHeight;
QString address;
painter.setPen(viewport()->palette().color(QPalette::WindowText));
for(int row = 0; row <= dataVisible.size()/mBytesPerLine; row++){
QString str = QString("%1").arg(startPos + mBytesPerLine*row, nBlockAddress*4, 16, QChar('0')).toUpper();
int i = 0;
address = "";
while(i < nBlockAddress){
address += str.mid(i*4, 4) + ":";
i++;
}
address.remove(address.size()-1, 1);
painter.drawText(pxWidth/2 -offsetX , y, address);
y+=pxHeight;
}
int x;
int lx = addressWidth() +pxWidth;
painter.drawLine(lx-offsetX, 0, lx-offsetX, height());
lx += pxWidth/2;
y = pxHeight;
//hex data
x = lx-offsetX+3*pxWidth;
int w = 3*pxWidth;
for(int col =0; col < mBytesPerLine/2; col++){
painter.fillRect(x-pxWidth/2, 0, w, height(), viewport()->palette().color(QPalette::AlternateBase));
x+= 6*pxWidth;
}
int bPos = 0;
for(int row=0; row < nRowsVisible; row++){
x = lx-offsetX;
for(int col =0; (col < mBytesPerLine) && (bPos < dataHex.size()) ; col++){
QString str = dataHex.mid(bPos*2,2).toUpper();
painter.drawText(x, y, str);
x += 3*pxWidth;
bPos += 1;
}
y+= pxHeight;
}
lx = addressWidth() + hexWidth();
painter.drawLine(lx-offsetX, 0, lx-offsetX, height());
lx += pxWidth/2;
bPos = 0;
y = pxHeight ;
int ch;
for(int row=0; row < nRowsVisible; row++){
x = lx-offsetX;
for(int col =0; (col < mBytesPerLine) && (bPos < dataVisible.size()) ; col++){
ch = (uchar)dataVisible.at(bPos);
if ( ch < 0x20 )
ch = '.';
painter.drawText(x, y, QChar(ch));
x += 2*pxWidth;
bPos += 1;
}
y+= pxHeight;
}
}
void MemoryViewer::adjustContent()
{
int w = addressWidth() + hexWidth() + asciiWidth();
horizontalScrollBar()->setRange(0, w - viewport()->width());
horizontalScrollBar()->setPageStep(viewport()->width());
nRowsVisible = viewport()->height()/pxHeight;
int val = verticalScrollBar()->value();
startPos = (qint64)val*mBytesPerLine;
endPos = startPos + nRowsVisible*mBytesPerLine -1;
int lineCount = size/mBytesPerLine;
verticalScrollBar()->setRange(0, lineCount-nRowsVisible);
verticalScrollBar()->setPageStep(nRowsVisible);
if(endPos >= size){
endPos = size-1;
}
dataVisible = data(startPos, endPos-startPos + mBytesPerLine +1);
dataHex = dataVisible.toHex();
viewport()->update();
}
An advantage of the implementation is that you do not have to load all the bytes directly since you can pass an object that inherits from QIODevice such as QFile and read the data when the view needs it by eliminating the memory overhead. In addition you can pass a QByteArray
In the following link you will find an example

QMetaMethod from member function pointer

Given a pointer to a method of a QObject derived class: Is there a way of getting the QMetaMethod of the method the pointer is pointing to? I am basically looking for a function like QMetaMethod::fromSignal, but for slots.
Note:
I tried getting the index through static_metacall with QMetaObject::IndexOfMethod and using that for QMetaObject::method:
void(Class::*method)() = &Class::method;
int methodIndex = -1;
void *metaArgs[] = {&methodIndex, reinterpret_cast<void **>(&method)};
const QMetaObject mo = Class::staticMetaObject;
mo.static_metacall(QMetaObject::IndexOfMethod, 0, metaArgs);
qDebug() << methodIndex;
// QMetaMethod mm = mo.method(methodIndex)
The output is always -1.

At the moment, the only solution is to modify moc. The patch is rather trivial, though:
diff --git a/src/tools/moc/generator.cpp b/src/tools/moc/generator.cpp
index d831edf..7dcefcc 100644
--- a/src/tools/moc/generator.cpp
+++ b/src/tools/moc/generator.cpp
## -1311,15 +1311,12 ## void Generator::generateStaticMetacall()
isUsed_a = true;
}
- }
- if (!cdef->signalList.isEmpty()) {
- Q_ASSERT(needElse); // if there is signal, there was method.
fprintf(out, " else if (_c == QMetaObject::IndexOfMethod) {\n");
fprintf(out, " int *result = reinterpret_cast<int *>(_a[0]);\n");
fprintf(out, " void **func = reinterpret_cast<void **>(_a[1]);\n");
bool anythingUsed = false;
- for (int methodindex = 0; methodindex < cdef->signalList.size(); ++methodindex) {
- const FunctionDef &f = cdef->signalList.at(methodindex);
+ for (int methodindex = 0; methodindex < methodList.size(); ++methodindex) {
+ const FunctionDef &f = methodList.at(methodindex);
if (f.wasCloned || !f.inPrivateClass.isEmpty() || f.isStatic)
continue;
anythingUsed = true;
The following then works as expected:
// https://github.com/KubaO/stackoverflown/tree/master/questions/metamethod-lookup-24577095
#include <QtCore>
class MyObject : public QObject {
Q_OBJECT
public:
Q_SLOT void aSlot() {}
Q_SLOT void aSlot2(int) {}
Q_SLOT int aSlot3(int) { return 0; }
Q_SIGNAL void aSignal();
Q_SIGNAL void aSignal2(int);
};
template <typename Func> int indexOfMethod(Func method)
{
using FuncType = QtPrivate::FunctionPointer<Func>;
int methodIndex = -1;
void *metaArgs[] = {&methodIndex, reinterpret_cast<void **>(&method)};
auto mo = FuncType::Object::staticMetaObject;
mo.static_metacall(QMetaObject::IndexOfMethod, 0, metaArgs);
return methodIndex;
}
int main(int argc, char *argv[])
{
QCoreApplication a(argc, argv);
qDebug() << indexOfMethod(&MyObject::aSlot)
<< indexOfMethod(&MyObject::aSlot3) << indexOfMethod(&MyObject::aSignal2);
return 0;
}
#include "main.moc"

Get index of QPushButton on 2D array QPushButton

I have an 2D array QPushButton, how can I get index of the button when user clicks on its? such as When user clicks on the button a[2][3] it will show (2,3) ?

The example looks like this:
Qt 4/5 Using Object Names
You can give your buttons unique object names. The names should ideally be valid C++ identifiers.
// https://github.com/KubaO/stackoverflown/tree/master/questions/button-grid-22641306
#include <QtGui>
#if QT_VERSION_MAJOR >= 5
#include <QtWidgets>
#endif
struct Display : QLabel {
Q_SLOT void onClicked() {
auto const elements = sender()->objectName().split('_');
auto const i = elements.at(1).toInt();
auto const j = elements.at(2).toInt();
setText(QString{"(%1,%2)"}.arg(i).arg(j));
}
Q_OBJECT
};
int main(int argc, char *argv[])
{
QApplication a{argc, argv};
QWidget window;
QGridLayout layout{&window};
QVarLengthArray<QPushButton, 12> buttons(12);
Display display;
const int rows = 4, columns = 3;
for (int i = 0; i < rows; ++ i)
for (int j = 0; j < columns; ++j) {
auto & button = buttons[i*columns+j];
button.setText(QString{"(%1,%2)"}.arg(i).arg(j));
button.setObjectName(QString{"buton_%1_%2"}.arg(i).arg(j));
layout.addWidget(&button, i, j);
display.connect(&button, SIGNAL(clicked()), SLOT(onClicked()));
}
layout.addWidget(&display, rows, 0, 1, columns);
window.show();
return a.exec();
}
#include "main.moc"
Qt 5 - Using Lambdas
In Qt 5 and C++11, you should use functors to generate custom slot for each button, on the fly. For example:
// https://github.com/KubaO/stackoverflown/tree/master/questions/button-grid-22641306
#include <QtWidgets>
int main(int argc, char *argv[])
{
QApplication a{argc, argv};
QWidget window;
QGridLayout layout{&window};
QVarLengthArray<QPushButton, 12> buttons(12);
QLabel display;
const int rows = 4, columns = 3;
for (int i = 0; i < rows; ++ i)
for (int j = 0; j < columns; ++j) {
auto text = QStringLiteral("(%1,%2)").arg(i).arg(j);
auto & button = buttons[i*columns+j];
button.setText(text);
layout.addWidget(&button, i, j);
QObject::connect(&button, &QPushButton::clicked, [&display, text] {
display.setText(text);
});
}
layout.addWidget(&display, rows, 0, 1, columns);
window.show();
return a.exec();
}
Qt 4/5 - Using QSignalMapper
QSignalMapper is pretty much designed for what you want. It lets you map a QObject* to "something else", like a string. For example:
#include <QtGui>
#if QT_VERSION_MAJOR >= 5
#include <QtWidgets>
#endif
int main(int argc, char *argv[])
{
QApplication a{argc, argv};
QSignalMapper mapper;
QWidget window;
QGridLayout layout{&window};
QVarLengthArray<QPushButton, 12> buttons(12);
QLabel display;
const int rows = 4, columns = 3;
for (int i = 0; i < rows; ++ i)
for (int j = 0; j < columns; ++j) {
auto text = QString{"(%1,%2)"}.arg(i).arg(j);
auto & button = buttons[i*columns+j];
button.setText(text);
layout.addWidget(&button, i, j);
mapper.connect(&button, SIGNAL(clicked()), SLOT(map()));
mapper.setMapping(&button, text);
}
display.connect(&mapper, SIGNAL(mapped(QString)), SLOT(setText(QString)));
layout.addWidget(&display, rows, 0, 1, columns);
window.show();
return a.exec();
}
Qt 4/5 - Using the Property System
You can leverage the fact that a QWidget is a QObject. QObjects have a property system, so you can set each button's index as a property, and then retrieve it in the slot connected to the clicked() signal. For example:
#include <QtGui>
#if QT_VERSION_MAJOR >= 5
#include <QtWidgets>
#endif
const char kIndex[] = "index";
struct Display : QLabel {
Q_SLOT void onClicked() {
setText(sender()->property(kIndex).toString());
}
Q_OBJECT
};
int main(int argc, char *argv[])
{
QApplication a{argc, argv};
QWidget window;
QGridLayout layout{&window};
QVarLengthArray<QPushButton, 12> buttons(12);
Display display;
const int rows = 4, columns = 3;
for (int i = 0; i < rows; ++ i)
for (int j = 0; j < columns; ++j) {
auto index = QString{"(%1,%2)"}.arg(i).arg(j);
auto & button = buttons[i*columns+j];
button.setText(index);
button.setProperty(kIndex, index);
layout.addWidget(&button, i, j);
display.connect(&button, SIGNAL(clicked()), SLOT(onClicked()));
}
layout.addWidget(&display, rows, 0, 1, columns);
window.show();
return a.exec();
}
#include "main.moc"

in general, you would have to loop over the array and test the event target for equality with each element until you reach the correct index