##// END OF EJS Templates
Bug fix for bar presenters. It appears that order of childItems may change. Relying on order caused crash
Bug fix for bar presenters. It appears that order of childItems may change. Relying on order caused crash

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r244:615e346403e5
r256:bd68fc4fe7ab
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widget.cpp
175 lines | 5.6 KiB | text/x-c | CppLexer
/*!
\class Widget
\brief Ui for the application.
*/
#include "widget.h"
#include <QGridLayout>
#include <QPushButton>
#include <QLabel>
#include <QSqlQuery>
#include <qscatterseries.h>
#include <qchartview.h>
#include <qchartaxis.h>
#include <qbarchartseries.h>
#include <qbarcategory.h>
#include <qbarset.h>
#include <QListWidget>
#include <QPrinter>
#include <QPrintDialog>
QTCOMMERCIALCHART_USE_NAMESPACE
Widget::Widget(QWidget *parent)
: QWidget(parent)
{
setGeometry(100, 100, 1000, 600);
// right panel layout
countrieslist = new QListWidget;
countrieslist->setSelectionMode(QAbstractItemView::MultiSelection);
yearslist = new QListWidget;
yearslist->setSelectionMode(QAbstractItemView::ExtendedSelection);
for (int i = 1990; i < 2011; i++)
yearslist->addItem(QString("%1").arg(i));
QPushButton* refreshButton = new QPushButton(tr("Refresh"));
connect(refreshButton, SIGNAL(clicked()), this, SLOT(refreshChart()));
QPushButton* printButton = new QPushButton(tr("Print chart"));
connect(printButton, SIGNAL(clicked()), this, SLOT(printChart()));
QVBoxLayout* rightPanelLayout = new QVBoxLayout;
rightPanelLayout->addWidget(countrieslist);
rightPanelLayout->addWidget(yearslist);
rightPanelLayout->addWidget(refreshButton);
rightPanelLayout->addWidget(printButton);
rightPanelLayout->setStretch(0, 1);
rightPanelLayout->setStretch(1, 0);
// main layout
chartArea = new QChartView(this);
chartArea->setChartTitle("GDP by country");
QGridLayout* mainLayout = new QGridLayout;
mainLayout->addWidget(chartArea, 0, 0);
mainLayout->addLayout(rightPanelLayout, 0, 1);
mainLayout->setColumnStretch(0,1);
setLayout(mainLayout);
// connect to the database
db = QSqlDatabase::addDatabase("QSQLITE");
db.setDatabaseName("gdpData");
if(!db.open())
{
qDebug() << "could not open database. SQLite db file missing (?)";
return;
}
// get the list of all countires and regions.
QSqlQuery query;
query.exec("SELECT DISTINCT country FROM gdp2");
// add the countries to the country filter
while (query.next()) {
countrieslist->addItem(query.value(0).toString());
}
// hide axis X labels
QChartAxis* axis = chartArea->axisX();
axis->setLabelsVisible(false);
// newAxis.setLabelsOrientation(QChartAxis::LabelsOrientationSlide);
}
Widget::~Widget()
{
//
db.close();
}
/*!
refreshes the chart
*/
void Widget::refreshChart()
{
// chartArea->
// selected countries items list is not sorted. copy the values to QStringlist and sort them.
QStringList selectedCountriesStrings;
QList<QListWidgetItem*> selectedCountriesItems = countrieslist->selectedItems();
for (int i = 0; i < selectedCountriesItems.size(); i++)
selectedCountriesStrings.append(selectedCountriesItems[i]->text());
selectedCountriesStrings.sort();
// use the sorted selected coutries list to initialize BarCategory
QBarCategory* category = new QBarCategory;
for (int i = 0; i < selectedCountriesStrings.size(); i++)
*category << selectedCountriesStrings[i];
QBarChartSeries* series0 = new QBarChartSeries(category);
// prepare the selected counries SQL query
QString countriesQuery = "country IN (";
for (int i = 0; i < selectedCountriesStrings.size(); i++)
{
countriesQuery.append("'" + selectedCountriesStrings[i] + "'");
if ( i < selectedCountriesStrings.size() - 1)
countriesQuery.append(",");
else
countriesQuery.append(")");
}
QSqlQuery query;
// selected years items list is not sorted. copy the values to QList<Integer> and sort them.
QList<int> selectedYearsInts;
QList<QListWidgetItem*> selectedYearsItems = yearslist->selectedItems();
for (int i = 0; i < selectedYearsItems.size(); i++)
selectedYearsInts.append(selectedYearsItems[i]->text().toInt());
qSort(selectedYearsInts);
// perform a query for each selected year
for (int i = 0; i < selectedYearsInts.size(); i++)
{
query.exec("SELECT country,gdpvalue FROM gdp2 where year=" + QString("%1").arg(selectedYearsInts[i]) + " AND " + countriesQuery);
QBarSet* barSet = new QBarSet;
// while (query.next()) {
// qDebug() << query.value(0).toString() << " : " << query.value(1).toString();
// }
query.first();
// the data for some of the coutries for some years might be missing.
// QBarChart needs bars to have same size
for (int k = 0; k < selectedCountriesStrings.size(); k++)
{
if (selectedCountriesStrings[k] == query.value(0).toString())
{
*barSet << query.value(1).toReal();
qDebug() << query.value(0).toString() << query.value(1).toReal() << " : " << QString("%1").arg(selectedYearsInts[i]);
query.next();
}
else
{
// data missing, put 0
*barSet << 0.0f;
qDebug() << "Putting 0 for Bosnia" << " : " << QString("%1").arg(selectedYearsInts[i]);
}
}
series0->addBarSet(barSet);
}
// add the serie to the chart
chartArea->addSeries(series0);
}
void Widget::printChart()
{
QPrinter printer;
// QPrinter printer(QPrinter::HighResolution);
printer.setOutputFormat(QPrinter::PdfFormat);
printer.setOrientation(QPrinter::Landscape);
printer.setOutputFileName("print.pdf");
QPainter painter;
painter.begin(&printer);
chartArea->render(&painter);
}