qt_demoe/third/qcustomplotdemo/frmexample/frmsimple.cpp

55 lines
2.3 KiB
C++

#include "frmsimple.h"
#include "ui_frmsimple.h"
#include "qdebug.h"
frmSimple::frmSimple(QWidget *parent) : QWidget(parent), ui(new Ui::frmSimple)
{
ui->setupUi(this);
this->initForm();
}
frmSimple::~frmSimple()
{
delete ui;
}
void frmSimple::initForm()
{
// add two new graphs and set their look:
ui->customPlot->addGraph();
ui->customPlot->graph(0)->setPen(QPen(Qt::blue)); // line color blue for first graph
ui->customPlot->graph(0)->setBrush(QBrush(QColor(0, 0, 255, 20))); // first graph will be filled with translucent blue
ui->customPlot->addGraph();
ui->customPlot->graph(1)->setPen(QPen(Qt::red)); // line color red for second graph
// generate some points of data (y0 for first, y1 for second graph):
QVector<double> x(251), y0(251), y1(251);
for (int i = 0; i < 251; ++i) {
x[i] = i;
y0[i] = qExp(-i / 150.0) * qCos(i / 10.0); // exponentially decaying cosine
y1[i] = qExp(-i / 150.0); // exponential envelope
}
// configure right and top axis to show ticks but no labels:
// (see QCPAxisRect::setupFullAxesBox for a quicker method to do this)
ui->customPlot->xAxis2->setVisible(true);
ui->customPlot->xAxis2->setTickLabels(false);
ui->customPlot->yAxis2->setVisible(true);
ui->customPlot->yAxis2->setTickLabels(false);
// make left and bottom axes always transfer their ranges to right and top axes:
connect(ui->customPlot->xAxis, SIGNAL(rangeChanged(QCPRange)), ui->customPlot->xAxis2, SLOT(setRange(QCPRange)));
connect(ui->customPlot->yAxis, SIGNAL(rangeChanged(QCPRange)), ui->customPlot->yAxis2, SLOT(setRange(QCPRange)));
// pass data points to graphs:
ui->customPlot->graph(0)->setData(x, y0);
ui->customPlot->graph(1)->setData(x, y1);
// let the ranges scale themselves so graph 0 fits perfectly in the visible area:
ui->customPlot->graph(0)->rescaleAxes();
// same thing for graph 1, but only enlarge ranges (in case graph 1 is smaller than graph 0):
ui->customPlot->graph(1)->rescaleAxes(true);
// Note: we could have also just called customPlot->rescaleAxes(); instead
// Allow user to drag axis ranges with mouse, zoom with mouse wheel and select graphs by clicking:
ui->customPlot->setInteractions(QCP::iRangeDrag | QCP::iRangeZoom | QCP::iSelectPlottables);
}