Sources_For_Linux/Qwt/doc/man/man3/QwtDial.3

.TH "QwtDial" 3 "Mon Dec 28 2020" "Version 6.1.6" "Qwt User's Guide" \" -*- nroff -*-
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.SH NAME
QwtDial \- \fBQwtDial\fP class provides a rounded range control\&.  

.SH SYNOPSIS
.br
.PP
.PP
\fC#include <qwt_dial\&.h>\fP
.PP
Inherits \fBQwtAbstractSlider\fP\&.
.PP
Inherited by \fBQwtAnalogClock\fP, and \fBQwtCompass\fP\&.
.SS "Public Types"

.in +1c
.ti -1c
.RI "enum \fBShadow\fP { \fBPlain\fP = QFrame::Plain, \fBRaised\fP = QFrame::Raised, \fBSunken\fP = QFrame::Sunken }"
.br
.RI "Frame shadow\&. "
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.RI "enum \fBMode\fP { \fBRotateNeedle\fP, \fBRotateScale\fP }"
.br
.RI "Mode controlling whether the needle or the scale is rotating\&. "
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.SS "Public Member Functions"

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.RI "\fBQwtDial\fP (QWidget *parent=NULL)"
.br
.RI "Constructor\&. "
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.RI "virtual \fB~QwtDial\fP ()"
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.RI "Destructor\&. "
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.RI "void \fBsetFrameShadow\fP (\fBShadow\fP)"
.br
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.RI "\fBShadow\fP \fBframeShadow\fP () const"
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.RI "void \fBsetLineWidth\fP (int)"
.br
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.RI "int \fBlineWidth\fP () const"
.br
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.RI "void \fBsetMode\fP (\fBMode\fP)"
.br
.RI "Change the mode of the dial\&. "
.ti -1c
.RI "\fBMode\fP \fBmode\fP () const"
.br
.ti -1c
.RI "void \fBsetScaleArc\fP (double minArc, double maxArc)"
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.RI "void \fBsetMinScaleArc\fP (double)"
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.RI "double \fBminScaleArc\fP () const"
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.RI "void \fBsetMaxScaleArc\fP (double)"
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.RI "double \fBmaxScaleArc\fP () const"
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.RI "virtual void \fBsetOrigin\fP (double)"
.br
.RI "Change the origin\&. "
.ti -1c
.RI "double \fBorigin\fP () const"
.br
.ti -1c
.RI "void \fBsetNeedle\fP (\fBQwtDialNeedle\fP *)"
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.ti -1c
.RI "const \fBQwtDialNeedle\fP * \fBneedle\fP () const"
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.RI "\fBQwtDialNeedle\fP * \fBneedle\fP ()"
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.RI "QRect \fBboundingRect\fP () const"
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.RI "QRect \fBinnerRect\fP () const"
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.RI "virtual QRect \fBscaleInnerRect\fP () const"
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.RI "virtual QSize \fBsizeHint\fP () const"
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.RI "virtual QSize \fBminimumSizeHint\fP () const"
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.ti -1c
.RI "void \fBsetScaleDraw\fP (\fBQwtRoundScaleDraw\fP *)"
.br
.ti -1c
.RI "\fBQwtRoundScaleDraw\fP * \fBscaleDraw\fP ()"
.br
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.RI "const \fBQwtRoundScaleDraw\fP * \fBscaleDraw\fP () const"
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.in -1c
.SS "Protected Member Functions"

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.RI "virtual void \fBwheelEvent\fP (QWheelEvent *)"
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.RI "virtual void \fBpaintEvent\fP (QPaintEvent *)"
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.RI "virtual void \fBchangeEvent\fP (QEvent *)"
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.RI "virtual void \fBdrawFrame\fP (QPainter *)"
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.RI "virtual void \fBdrawContents\fP (QPainter *) const"
.br
.RI "Draw the contents inside the frame\&. "
.ti -1c
.RI "virtual void \fBdrawFocusIndicator\fP (QPainter *) const"
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.ti -1c
.RI "void \fBinvalidateCache\fP ()"
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.RI "virtual void \fBdrawScale\fP (QPainter *, const QPointF &center, double radius) const"
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.RI "virtual void \fBdrawScaleContents\fP (QPainter *painter, const QPointF &center, double radius) const"
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.RI "virtual void \fBdrawNeedle\fP (QPainter *, const QPointF &, double radius, double direction, QPalette::ColorGroup) const"
.br
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.RI "virtual double \fBscrolledTo\fP (const QPoint &) const"
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.RI "Determine the value for a new position of the slider handle\&. "
.ti -1c
.RI "virtual bool \fBisScrollPosition\fP (const QPoint &) const"
.br
.RI "Determine what to do when the user presses a mouse button\&. "
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.RI "virtual void \fBsliderChange\fP ()"
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.RI "Calling update() "
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.RI "virtual void \fBscaleChange\fP ()"
.br
.in -1c
.SS "Additional Inherited Members"
.SH "Detailed Description"
.PP 
\fBQwtDial\fP class provides a rounded range control\&. 

\fBQwtDial\fP is intended as base class for dial widgets like speedometers, compass widgets, clocks \&.\&.\&.
.PP
.PP
A dial contains a scale and a needle indicating the current value of the dial\&. Depending on Mode one of them is fixed and the other is rotating\&. If not \fBisReadOnly()\fP the dial can be rotated by dragging the mouse or using keyboard inputs (see \fBQwtAbstractSlider::keyPressEvent()\fP)\&. A dial might be wrapping, what means a rotation below/above one limit continues on the other limit (f\&.e compass)\&. The scale might cover any arc of the dial, its values are related to the \fBorigin()\fP of the dial\&.
.PP
Often dials have to be updated very often according to values from external devices\&. For these high refresh rates \fBQwtDial\fP caches as much as possible\&. For derived classes it might be necessary to clear these caches manually according to attribute changes using \fBinvalidateCache()\fP\&.
.PP
\fBSee also\fP
.RS 4
\fBQwtCompass\fP, \fBQwtAnalogClock\fP, \fBQwtDialNeedle\fP 
.RE
.PP
\fBNote\fP
.RS 4
The controls and dials examples shows different types of dials\&. 
.PP
QDial is more similar to \fBQwtKnob\fP than to \fBQwtDial\fP 
.RE
.PP

.SH "Member Enumeration Documentation"
.PP 
.SS "enum \fBQwtDial::Mode\fP"

.PP
Mode controlling whether the needle or the scale is rotating\&. 
.PP
\fBEnumerator\fP
.in +1c
.TP
\fB\fIRotateNeedle \fP\fP
The needle is rotating\&. 
.TP
\fB\fIRotateScale \fP\fP
The needle is fixed, the scales are rotating\&. 
.SS "enum \fBQwtDial::Shadow\fP"

.PP
Frame shadow\&. Unfortunately it is not possible to use QFrame::Shadow as a property of a widget that is not derived from QFrame\&. The following enum is made for the designer only\&. It is safe to use QFrame::Shadow instead\&. 
.PP
\fBEnumerator\fP
.in +1c
.TP
\fB\fIPlain \fP\fP
QFrame::Plain\&. 
.TP
\fB\fIRaised \fP\fP
QFrame::Raised\&. 
.TP
\fB\fISunken \fP\fP
QFrame::Sunken\&. 
.SH "Constructor & Destructor Documentation"
.PP 
.SS "QwtDial::QwtDial (QWidget * parent = \fCNULL\fP)\fC [explicit]\fP"

.PP
Constructor\&. 
.PP
\fBParameters\fP
.RS 4
\fIparent\fP Parent widget
.RE
.PP
Create a dial widget with no needle\&. The scale is initialized to [ 0\&.0, 360\&.0 ] and 360 steps ( \fBQwtAbstractSlider::setTotalSteps()\fP )\&. The origin of the scale is at 90°,
.PP
The value is set to 0\&.0\&.
.PP
The default mode is \fBQwtDial::RotateNeedle\fP\&. 
.SH "Member Function Documentation"
.PP 
.SS "QRect QwtDial::boundingRect () const"

.PP
\fBReturns\fP
.RS 4
bounding rectangle of the dial including the frame 
.RE
.PP
\fBSee also\fP
.RS 4
\fBsetLineWidth()\fP, \fBscaleInnerRect()\fP, \fBinnerRect()\fP 
.RE
.PP

.SS "void QwtDial::changeEvent (QEvent * event)\fC [protected]\fP, \fC [virtual]\fP"
Change Event handler 
.PP
\fBParameters\fP
.RS 4
\fIevent\fP Change event
.RE
.PP
Invalidates internal paint caches if necessary 
.SS "void QwtDial::drawContents (QPainter * painter) const\fC [protected]\fP, \fC [virtual]\fP"

.PP
Draw the contents inside the frame\&. QPalette::Window is the background color outside of the frame\&. QPalette::Base is the background color inside the frame\&. QPalette::WindowText is the background color inside the scale\&.
.PP
\fBParameters\fP
.RS 4
\fIpainter\fP Painter
.RE
.PP
\fBSee also\fP
.RS 4
\fBboundingRect()\fP, \fBinnerRect()\fP, \fBscaleInnerRect()\fP, QWidget::setPalette() 
.RE
.PP

.SS "void QwtDial::drawFocusIndicator (QPainter * painter) const\fC [protected]\fP, \fC [virtual]\fP"
Draw the focus indicator 
.PP
\fBParameters\fP
.RS 4
\fIpainter\fP Painter 
.RE
.PP

.SS "void QwtDial::drawFrame (QPainter * painter)\fC [protected]\fP, \fC [virtual]\fP"
Draw the frame around the dial
.PP
\fBParameters\fP
.RS 4
\fIpainter\fP Painter 
.RE
.PP
\fBSee also\fP
.RS 4
\fBlineWidth()\fP, \fBframeShadow()\fP 
.RE
.PP

.SS "void QwtDial::drawNeedle (QPainter * painter, const QPointF & center, double radius, double direction, QPalette::ColorGroup colorGroup) const\fC [protected]\fP, \fC [virtual]\fP"
Draw the needle
.PP
\fBParameters\fP
.RS 4
\fIpainter\fP Painter 
.br
\fIcenter\fP Center of the dial 
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\fIradius\fP Length for the needle 
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\fIdirection\fP Direction of the needle in degrees, counter clockwise 
.br
\fIcolorGroup\fP ColorGroup 
.RE
.PP

.PP
Reimplemented in \fBQwtAnalogClock\fP\&.
.SS "void QwtDial::drawScale (QPainter * painter, const QPointF & center, double radius) const\fC [protected]\fP, \fC [virtual]\fP"
Draw the scale
.PP
\fBParameters\fP
.RS 4
\fIpainter\fP Painter 
.br
\fIcenter\fP Center of the dial 
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\fIradius\fP Radius of the scale 
.RE
.PP

.SS "void QwtDial::drawScaleContents (QPainter * painter, const QPointF & center, double radius) const\fC [protected]\fP, \fC [virtual]\fP"
Draw the contents inside the scale
.PP
Paints nothing\&.
.PP
\fBParameters\fP
.RS 4
\fIpainter\fP Painter 
.br
\fIcenter\fP Center of the contents circle 
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\fIradius\fP Radius of the contents circle 
.RE
.PP

.PP
Reimplemented in \fBQwtCompass\fP\&.
.SS "\fBQwtDial::Shadow\fP QwtDial::frameShadow () const"

.PP
\fBReturns\fP
.RS 4
Frame shadow /sa \fBsetFrameShadow()\fP, \fBlineWidth()\fP, QFrame::frameShadow() 
.RE
.PP

.SS "QRect QwtDial::innerRect () const"

.PP
\fBReturns\fP
.RS 4
bounding rectangle of the circle inside the frame 
.RE
.PP
\fBSee also\fP
.RS 4
\fBsetLineWidth()\fP, \fBscaleInnerRect()\fP, \fBboundingRect()\fP 
.RE
.PP

.SS "void QwtDial::invalidateCache ()\fC [protected]\fP"
Invalidate the internal caches used to speed up repainting 
.SS "bool QwtDial::isScrollPosition (const QPoint & pos) const\fC [protected]\fP, \fC [virtual]\fP"

.PP
Determine what to do when the user presses a mouse button\&. 
.PP
\fBParameters\fP
.RS 4
\fIpos\fP Mouse position
.RE
.PP
\fBReturn values\fP
.RS 4
\fITrue,when\fP the inner circle contains pos 
.RE
.PP
\fBSee also\fP
.RS 4
\fBscrolledTo()\fP 
.RE
.PP

.PP
Implements \fBQwtAbstractSlider\fP\&.
.SS "int QwtDial::lineWidth () const"

.PP
\fBReturns\fP
.RS 4
Line width of the frame 
.RE
.PP
\fBSee also\fP
.RS 4
\fBsetLineWidth()\fP, \fBframeShadow()\fP, \fBlineWidth()\fP 
.RE
.PP

.SS "double QwtDial::maxScaleArc () const"

.PP
\fBReturns\fP
.RS 4
Upper limit of the scale arc 
.RE
.PP
\fBSee also\fP
.RS 4
\fBsetScaleArc()\fP 
.RE
.PP

.SS "QSize QwtDial::minimumSizeHint () const\fC [virtual]\fP"

.PP
\fBReturns\fP
.RS 4
Minimum size hint 
.RE
.PP
\fBSee also\fP
.RS 4
\fBsizeHint()\fP 
.RE
.PP

.SS "double QwtDial::minScaleArc () const"

.PP
\fBReturns\fP
.RS 4
Lower limit of the scale arc 
.RE
.PP
\fBSee also\fP
.RS 4
\fBsetScaleArc()\fP 
.RE
.PP

.SS "\fBQwtDial::Mode\fP QwtDial::mode () const"

.PP
\fBReturns\fP
.RS 4
Mode of the dial\&. 
.RE
.PP
\fBSee also\fP
.RS 4
\fBsetMode()\fP, \fBorigin()\fP, \fBsetScaleArc()\fP, \fBvalue()\fP 
.RE
.PP

.SS "\fBQwtDialNeedle\fP * QwtDial::needle ()"

.PP
\fBReturns\fP
.RS 4
needle 
.RE
.PP
\fBSee also\fP
.RS 4
\fBsetNeedle()\fP 
.RE
.PP

.SS "const \fBQwtDialNeedle\fP * QwtDial::needle () const"

.PP
\fBReturns\fP
.RS 4
needle 
.RE
.PP
\fBSee also\fP
.RS 4
\fBsetNeedle()\fP 
.RE
.PP

.SS "double QwtDial::origin () const"
The origin is the angle where scale and needle is relative to\&.
.PP
\fBReturns\fP
.RS 4
Origin of the dial 
.RE
.PP
\fBSee also\fP
.RS 4
\fBsetOrigin()\fP 
.RE
.PP

.SS "void QwtDial::paintEvent (QPaintEvent * event)\fC [protected]\fP, \fC [virtual]\fP"
Paint the dial 
.PP
\fBParameters\fP
.RS 4
\fIevent\fP Paint event 
.RE
.PP

.SS "void QwtDial::scaleChange ()\fC [protected]\fP, \fC [virtual]\fP"
Invalidate the internal caches and call \fBQwtAbstractSlider::scaleChange()\fP 
.PP
Reimplemented from \fBQwtAbstractSlider\fP\&.
.SS "\fBQwtRoundScaleDraw\fP * QwtDial::scaleDraw ()"

.PP
\fBReturns\fP
.RS 4
the scale draw 
.RE
.PP

.SS "const \fBQwtRoundScaleDraw\fP * QwtDial::scaleDraw () const"

.PP
\fBReturns\fP
.RS 4
the scale draw 
.RE
.PP

.SS "QRect QwtDial::scaleInnerRect () const\fC [virtual]\fP"

.PP
\fBReturns\fP
.RS 4
rectangle inside the scale 
.RE
.PP
\fBSee also\fP
.RS 4
\fBsetLineWidth()\fP, \fBboundingRect()\fP, \fBinnerRect()\fP 
.RE
.PP

.SS "double QwtDial::scrolledTo (const QPoint & pos) const\fC [protected]\fP, \fC [virtual]\fP"

.PP
Determine the value for a new position of the slider handle\&. 
.PP
\fBParameters\fP
.RS 4
\fIpos\fP Mouse position
.RE
.PP
\fBReturns\fP
.RS 4
Value for the mouse position 
.RE
.PP
\fBSee also\fP
.RS 4
\fBisScrollPosition()\fP 
.RE
.PP

.PP
Implements \fBQwtAbstractSlider\fP\&.
.SS "void QwtDial::setFrameShadow (\fBShadow\fP shadow)"
Sets the frame shadow value from the frame style\&.
.PP
\fBParameters\fP
.RS 4
\fIshadow\fP Frame shadow 
.RE
.PP
\fBSee also\fP
.RS 4
\fBsetLineWidth()\fP, QFrame::setFrameShadow() 
.RE
.PP

.SS "void QwtDial::setLineWidth (int lineWidth)"
Sets the line width of the frame
.PP
\fBParameters\fP
.RS 4
\fIlineWidth\fP Line width 
.RE
.PP
\fBSee also\fP
.RS 4
\fBsetFrameShadow()\fP 
.RE
.PP

.SS "void QwtDial::setMaxScaleArc (double max)"
Set the upper limit for the scale arc
.PP
\fBParameters\fP
.RS 4
\fImax\fP Upper limit of the scale arc 
.RE
.PP
\fBSee also\fP
.RS 4
\fBsetScaleArc()\fP, \fBsetMinScaleArc()\fP 
.RE
.PP

.SS "void QwtDial::setMinScaleArc (double min)"
Set the lower limit for the scale arc
.PP
\fBParameters\fP
.RS 4
\fImin\fP Lower limit of the scale arc 
.RE
.PP
\fBSee also\fP
.RS 4
\fBsetScaleArc()\fP, \fBsetMaxScaleArc()\fP 
.RE
.PP

.SS "void QwtDial::setMode (\fBMode\fP mode)"

.PP
Change the mode of the dial\&. 
.PP
\fBParameters\fP
.RS 4
\fImode\fP New mode
.RE
.PP
In case of \fBQwtDial::RotateNeedle\fP the needle is rotating, in case of \fBQwtDial::RotateScale\fP, the needle points to \fBorigin()\fP and the scale is rotating\&.
.PP
The default mode is \fBQwtDial::RotateNeedle\fP\&.
.PP
\fBSee also\fP
.RS 4
\fBmode()\fP, \fBsetValue()\fP, \fBsetOrigin()\fP 
.RE
.PP

.SS "void QwtDial::setNeedle (\fBQwtDialNeedle\fP * needle)"
Set a needle for the dial
.PP
\fBParameters\fP
.RS 4
\fIneedle\fP Needle
.RE
.PP
\fBWarning\fP
.RS 4
The needle will be deleted, when a different needle is set or in \fB~QwtDial()\fP 
.RE
.PP

.SS "void QwtDial::setOrigin (double origin)\fC [virtual]\fP"

.PP
Change the origin\&. The origin is the angle where scale and needle is relative to\&.
.PP
\fBParameters\fP
.RS 4
\fIorigin\fP New origin 
.RE
.PP
\fBSee also\fP
.RS 4
\fBorigin()\fP 
.RE
.PP

.SS "void QwtDial::setScaleArc (double minArc, double maxArc)"
Change the arc of the scale
.PP
\fBParameters\fP
.RS 4
\fIminArc\fP Lower limit 
.br
\fImaxArc\fP Upper limit
.RE
.PP
\fBSee also\fP
.RS 4
\fBminScaleArc()\fP, \fBmaxScaleArc()\fP 
.RE
.PP

.SS "void QwtDial::setScaleDraw (\fBQwtRoundScaleDraw\fP * scaleDraw)"
Set an individual scale draw
.PP
The motivation for setting a scale draw is often to overload \fBQwtRoundScaleDraw::label()\fP to return individual tick labels\&.
.PP
\fBParameters\fP
.RS 4
\fIscaleDraw\fP Scale draw 
.RE
.PP
\fBWarning\fP
.RS 4
The previous scale draw is deleted 
.RE
.PP

.SS "QSize QwtDial::sizeHint () const\fC [virtual]\fP"

.PP
\fBReturns\fP
.RS 4
Size hint 
.RE
.PP
\fBSee also\fP
.RS 4
\fBminimumSizeHint()\fP 
.RE
.PP

.SS "void QwtDial::wheelEvent (QWheelEvent * event)\fC [protected]\fP, \fC [virtual]\fP"
Wheel Event handler 
.PP
\fBParameters\fP
.RS 4
\fIevent\fP Wheel event 
.RE
.PP

.PP
Reimplemented from \fBQwtAbstractSlider\fP\&.

.SH "Author"
.PP 
Generated automatically by Doxygen for Qwt User's Guide from the source code\&.