I solved the problem by changing the clearPlot method to the following:
void Plot::ClearPlot()
{
CurveData *data = static_cast<CurveData *>(d_curve->data());
data->clear();
QwtPlot::replot();
QwtPlot::repaint();
}
Question
This is my first question here and I believe that I havent seen anyone else asking for this specific problem but what I'm currently dealing with is a qwt plot that doesn't want to replot.
What I want to do: Call the replot() method to clear my current plot.
My problem: When calling replot() does not clear my current plot and my plots are drawn on top of eachother.
Here is a link to an image of my problem
As can be seen in the image, the new curves are drawn on top of the existing ones and this is what I want to solve.
Here is some of my code: (let me know if I missed some parts)
plot.cpp
#include "plot.h"
#include <qwt_plot.h>
#include <qwt_plot_grid.h>
#include <qwt_plot_layout.h>
#include <qwt_plot_canvas.h>
#include <qwt_plot_curve.h>
#include <qwt_plot_directpainter.h>
#include <qwt_curve_fitter.h>
#include <qwt_painter.h>
class CurveData: public QwtArraySeriesData<QPointF>
{
public:
CurveData()
{
}
virtual QRectF boundingRect() const
{
if ( d_boundingRect.width() < 0.0 )
d_boundingRect = qwtBoundingRect( *this );
return d_boundingRect;
}
inline void append( const QPointF &point )
{
d_samples += point;
}
void clear()
{
d_samples.clear();
d_samples.squeeze();
d_boundingRect = QRectF( 0.0, 0.0, -1.0, -1.0 );
}
};
Plot::Plot( QWidget *parent ):
QwtPlot( parent )
{
d_directPainter = new QwtPlotDirectPainter(this);
setAutoReplot(false);
setAxisScale(QwtPlot::yLeft, 0.014,0.016);
setAxisScale(QwtPlot::xBottom, 0, 1000);
d_curve = new QwtPlotCurve();
d_curve->setData(new CurveData());
d_curve->attach(this);
}
void Plot::AppendPoint(const QPointF &point)
{
CurveData *data = static_cast<CurveData *>(d_curve->data());
data->append(point);
}
void Plot::DrawCurveSegment()
{
CurveData *data = static_cast<CurveData *>(d_curve->data());
d_directPainter->drawSeries(d_curve, data->size()-11, data->size()-1);
}
void Plot::ClearPlot()
{
CurveData *data = static_cast<CurveData *>(d_curve->data());
data->clear();
QwtPlot::replot();
}
mainwindow.cpp
MainWindow::MainWindow(QWidget *parent):
QWidget( parent )
{
d_plot = new Plot();
counter = 0;
loopCounter = 0;
// ... //
}
void MainWindow::timerEvent(QTimerEvent *) {
if (counter>0 && counter%1000==0)
{
d_plot->ClearPlot();
d_plot->replot();
loopCounter++;
qDebug()<<"clear!";
}
for (int ii=0; ii<10;ii++)
{
double y = someArray[counter];
double x = (double)counter-((double)loopCounter*1000);
counter++;
d_plot->AppendPoint(QPointF(x,y));
}
d_plot->DrawCurveSegment();
}
Would very much appreciate if someone can see what I'm doing wrong.
Best regards!
La solution
I solved the problem by changing the clearPlot method to the following:
void Plot::ClearPlot()
{
CurveData *data = static_cast<CurveData *>(d_curve->data());
data->clear();
QwtPlot::replot();
QwtPlot::repaint();
}
Autres conseils
You can also do this:
QwtPlot::detachItems(QwtPlotItem::Rtti_PlotItem, true);