QwtSamplingThread Class Reference

A thread collecting samples at regular intervals. More...

#include <qwt_sampling_thread.h>

Inheritance diagram for QwtSamplingThread:

Public Slots
void	setInterval (double interval)
void	stop ()

Public Member Functions
virtual	~QwtSamplingThread ()
	Destructor.
double	interval () const
double	elapsed () const

Protected Member Functions
	QwtSamplingThread (QObject *parent=NULL)
	Constructor.
virtual void	run ()
virtual void	sample (double elapsed)=0

Detailed Description

A thread collecting samples at regular intervals.

Continuous signals are converted into a discrete signal by collecting samples at regular intervals. A discrete signal can be displayed by a QwtPlotSeriesItem on a QwtPlot widget.

QwtSamplingThread starts a thread calling periodically sample(), to collect and store ( or emit ) a single sample.

See also

QwtPlotCurve, QwtPlotSeriesItem

Member Function Documentation

double QwtSamplingThread::elapsed

(

)

const

Returns

Time (in ms) since the thread was started

See also

QThread::start(), run()

double QwtSamplingThread::interval

(

)

const

Returns

Interval (in ms), between 2 calls of sample()

See also

setInterval()

void QwtSamplingThread::run ( )

protectedvirtual

Loop collecting samples started from QThread::start()

See also

stop()

virtual void QwtSamplingThread::sample ( double  elapsed )

protectedpure virtual

Collect a sample

Parameters

elapsed

Time since the thread was started in milliseconds

void QwtSamplingThread::setInterval ( double  interval )

slot

Change the interval (in ms), when sample() is called. The default interval is 1000.0 ( = 1s )

Parameters

interval

Interval

See also

interval()

void QwtSamplingThread::stop ( )

slot

Terminate the collecting thread

See also

QThread::start(), run()