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QwtCounter

NAME

QwtCounter -

The Counter Widget.

SYNOPSIS

#include <qwt_counter.h>

Inherits QwtDoubleRange.

Public Types

enum Button { Button1, Button2, Button3, ButtonCnt }

Signals

void buttonReleased (double value)

void valueChanged (double value)

Public Member Functions

QwtCounter (QWidget *parent=NULL)

virtual ~QwtCounter ()

bool editable () const

void setEditable (bool)

void setNumButtons (int n)

int numButtons () const

void setIncSteps (QwtCounter::Button btn, int nSteps)

int incSteps (QwtCounter::Button btn) const

virtual void setValue (double)

virtual QSize sizeHint () const

virtual void polish ()

double step () const

void setStep (double s)

double minVal () const

void setMinValue (double m)

double maxVal () const

void setMaxValue (double m)

void setStepButton1 (int nSteps)

int stepButton1 () const

void setStepButton2 (int nSteps)

int stepButton2 () const

void setStepButton3 (int nSteps)

int stepButton3 () const

virtual double value () const

Protected Member Functions

virtual bool event (QEvent *)

virtual void wheelEvent (QWheelEvent *)

virtual void keyPressEvent (QKeyEvent *)

virtual void rangeChange ()

Detailed Description

The Counter Widget.

A Counter consists of a label displaying a number and one ore more (up to three) push buttons on each side of the label which can be used to increment or decrement the counter's value.

A Counter has a range from a minimum value to a maximum value and a step size. The range can be specified using QwtDblRange::setRange(). The counter's value is an integer multiple of the step size. The number of steps by which a button increments or decrements the value can be specified using QwtCounter::setIncSteps(). The number of buttons can be changed with QwtCounter::setNumButtons().

Holding the space bar down with focus on a button is the fastest method to step through the counter values. When the counter underflows/overflows, the focus is set to the smallest up/down button and counting is disabled. Counting is re-enabled on a button release event (mouse or space bar).

Example:

 #include '../include/qwt_counter.h>
 
 QwtCounter *cnt;
 
 cnt = new QwtCounter(parent, name);
 
 cnt->setRange(0.0, 100.0, 1.0);             // From 0.0 to 100, step 1.0
 cnt->setNumButtons(2);                      // Two buttons each side
 cnt->setIncSteps(QwtCounter::Button1, 1);   // Button 1 increments 1 step
 cnt->setIncSteps(QwtCounter::Button2, 20);  // Button 2 increments 20 steps
 
 connect(cnt, SIGNAL(valueChanged(double)), my_class, SLOT(newValue(double)));
 
 

 

Member Enumeration Documentation

enum QwtCounter::ButtonButton index

Constructor & Destructor Documentation

QwtCounter::QwtCounter (QWidget * parent = NULL) [explicit]The default number of buttons is set to 2. The default increments are:

*

Button 1: 1 step

*

Button 2: 10 steps

*

Button 3: 100 steps

Parameters:

parent

QwtCounter::~QwtCounter () [virtual]

Destructor.

Member Function Documentation

void QwtCounter::buttonReleased (double value) [signal]This signal is emitted when a button has been released

Parameters:

value The new value

bool QwtCounter::editable () const

returns whether the line edit is edatble. (default is yes)

bool QwtCounter::event (QEvent * e) [protected, virtual]Handle PolishRequest events

int QwtCounter::incSteps (QwtCounter::Button btn) constReturns:

the number of steps by which a specified button increments the value or 0 if the button is invalid.

Parameters:

btn One of QwtCounter::Button1, QwtCounter::Button2, QwtCounter::Button3

void QwtCounter::keyPressEvent (QKeyEvent * e) [protected, virtual]Handle key events

*

Ctrl + Qt::Key_Home Step to minValue()

*

Ctrl + Qt::Key_End Step to maxValue()

*

Qt::Key_Up Increment by incSteps(QwtCounter::Button1)

*

Qt::Key_Down Decrement by incSteps(QwtCounter::Button1)

*

Qt::Key_PageUp Increment by incSteps(QwtCounter::Button2)

*

Qt::Key_PageDown Decrement by incSteps(QwtCounter::Button2)

*

Shift + Qt::Key_PageUp Increment by incSteps(QwtCounter::Button3)

*

Shift + Qt::Key_PageDown Decrement by incSteps(QwtCounter::Button3)

double QwtCounter::maxVal () const

returns the maximum value of the range

double QwtCounter::minVal () const

returns the minimum value of the range

int QwtCounter::numButtons () constReturns:

The number of buttons on each side of the widget.

void QwtCounter::polish () [virtual]Sets the minimum width for the buttons

void QwtCounter::rangeChange () [protected, virtual]

Notify change of range. This function updates the enabled property of all buttons contained in QwtCounter.

Reimplemented from QwtDoubleRange.

void QwtCounter::setEditable (bool editable)

Allow/disallow the user to manually edit the value. Parameters:

editable true enables editing

See also:

editable()

void QwtCounter::setIncSteps (QwtCounter::Button btn, int nSteps)Specify the number of steps by which the value is incremented or decremented when a specified button is pushed.

Parameters:

btn One of QwtCounter::Button1, QwtCounter::Button2, QwtCounter::Button3
nSteps Number of steps

void QwtCounter::setMaxValue (double value)Set the maximum value of the range

Parameters:

value Maximum value

See also:

setMinValue(), maxVal()

void QwtCounter::setMinValue (double value)Set the minimum value of the range

Parameters:

value Minimum value

See also:

setMaxValue(), minVal()

void QwtCounter::setNumButtons (int n)

Specify the number of buttons on each side of the label. Parameters:

n Number of buttons

void QwtCounter::setStep (double stepSize)Set the step size

Parameters:

stepSize Step size

See also:

QwtDoubleRange::setStep()

Reimplemented from QwtDoubleRange.

void QwtCounter::setStepButton1 (int nSteps)Set the number of increment steps for button 1

Parameters:

nSteps Number of steps

void QwtCounter::setStepButton2 (int nSteps)Set the number of increment steps for button 2

Parameters:

nSteps Number of steps

void QwtCounter::setStepButton3 (int nSteps)Set the number of increment steps for button 3

Parameters:

nSteps Number of steps

void QwtCounter::setValue (double v) [virtual]

Set a new value. Parameters:

v new value Calls QwtDoubleRange::setValue and does all visual updates.

See also:

QwtDoubleRange::setValue()

Reimplemented from QwtDoubleRange.

QSize QwtCounter::sizeHint () const [virtual]

A size hint.

double QwtCounter::step () const

returns the step size

Reimplemented from QwtDoubleRange.

int QwtCounter::stepButton1 () const

returns the number of increment steps for button 1

int QwtCounter::stepButton2 () const

returns the number of increment steps for button 2

int QwtCounter::stepButton3 () const

returns the number of increment steps for button 3

double QwtCounter::value () const [virtual]Returns:

Current value

Reimplemented from QwtDoubleRange.

void QwtCounter::valueChanged (double value) [signal]This signal is emitted when the counter's value has changed

Parameters:

value The new value

void QwtCounter::wheelEvent (QWheelEvent * e) [protected, virtual]Handle wheel events

Parameters:

e Wheel event

Author

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