QwtPlot replot() works on Mac OS, but not in Linux!

The Problem:
I have a plot with controls for changing the scale (linear vs log) and for changing the min X and the max X values, then replot. But the code only works well on Mac OS, and not in Linux!

I start out with:

Code:

---

calibPlot->setAxisScaleEngine(QwtPlot::xBottom, new QwtLinearScaleEngine () );
    calibPlot->replot();

---

Then I call the control buttons: using a function: setupGraphControls();
In the function I define the controls, and connect them to corresponding SLOTS:

Code:

---

connect( axisXScale, SIGNAL( activated( const QString &)),
this, SLOT(xAxisScaleChange( const QString &) ) );
connect( axisXStart, SIGNAL( textChanged ( const QString & )),
this, SLOT(xAxisScaleMin( const QString & ) ) );
connect( axisXEnd, SIGNAL( textChanged( const QString &)),
this, SLOT(xAxisScaleMax( const QString &) ) );

---

The slots are coded as (one example):

Code:

---

void CentralPage::xAxisScaleMin( const QString &xMinVal) 
{ 
  bool ok; 
  const bool doReplot = calibPlot->autoReplot(); 
  calibPlot->setAxisScale(QwtPlot::xBottom, xMinVal.toInt(&ok,10),axisXEnd->text().toInt(&ok,10) );   
  calibPlot->setAutoReplot( doReplot ); 
  calibPlot->replot(); }
  }

---

In the connection statements, should I be using something else in place of "this" ? Has anyone else seen this issue, I use qwt-5.2.0.

Any more elegant ways of doing this?

// Sal Aguinaga
// Northwestern University

I have similar issue. The qwt examples with replot() function works with QT-X11, Qwt5.2 on red hat linux.
But they do not work with QT-embedded, Qwt5.2 on embedded montavista.