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diff --git a/doc/html/qrangecontrol.html b/doc/html/qrangecontrol.html new file mode 100644 index 0000000..8e9df9a --- /dev/null +++ b/doc/html/qrangecontrol.html @@ -0,0 +1,336 @@ +<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"> +<!-- /home/espenr/tmp/qt-3.3.8-espenr-2499/qt-x11-free-3.3.8/src/widgets/qrangecontrol.cpp:46 --> +<html> +<head> +<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1"> +<title>QRangeControl Class</title> +<style type="text/css"><!-- +fn { margin-left: 1cm; text-indent: -1cm; } +a:link { color: #004faf; text-decoration: none } +a:visited { color: #672967; text-decoration: none } +body { background: #ffffff; color: black; } +--></style> +</head> +<body> + +<table border="0" cellpadding="0" cellspacing="0" width="100%"> +<tr bgcolor="#E5E5E5"> +<td valign=center> + <a href="index.html"> +<font color="#004faf">Home</font></a> + | <a href="classes.html"> +<font color="#004faf">All Classes</font></a> + | <a href="mainclasses.html"> +<font color="#004faf">Main Classes</font></a> + | <a href="annotated.html"> +<font color="#004faf">Annotated</font></a> + | <a href="groups.html"> +<font color="#004faf">Grouped Classes</font></a> + | <a href="functions.html"> +<font color="#004faf">Functions</font></a> +</td> +<td align="right" valign="center"><img src="logo32.png" align="right" width="64" height="32" border="0"></td></tr></table><h1 align=center>QRangeControl Class Reference</h1> + +<p>The QRangeControl class provides an integer value within a range. +<a href="#details">More...</a> +<p><tt>#include <<a href="qrangecontrol-h.html">qrangecontrol.h</a>></tt> +<p>Inherited by <a href="qdial.html">QDial</a>, <a href="qscrollbar.html">QScrollBar</a>, <a href="qslider.html">QSlider</a>, and <a href="qspinbox.html">QSpinBox</a>. +<p><a href="qrangecontrol-members.html">List of all member functions.</a> +<h2>Public Members</h2> +<ul> +<li class=fn><a href="#QRangeControl"><b>QRangeControl</b></a> ()</li> +<li class=fn><a href="#QRangeControl-2"><b>QRangeControl</b></a> ( int minValue, int maxValue, int lineStep, int pageStep, int value )</li> +<li class=fn>virtual <a href="#~QRangeControl"><b>~QRangeControl</b></a> ()</li> +<li class=fn>int <a href="#value"><b>value</b></a> () const</li> +<li class=fn>void <a href="#setValue"><b>setValue</b></a> ( int value )</li> +<li class=fn>void <a href="#addPage"><b>addPage</b></a> ()</li> +<li class=fn>void <a href="#subtractPage"><b>subtractPage</b></a> ()</li> +<li class=fn>void <a href="#addLine"><b>addLine</b></a> ()</li> +<li class=fn>void <a href="#subtractLine"><b>subtractLine</b></a> ()</li> +<li class=fn>int <a href="#minValue"><b>minValue</b></a> () const</li> +<li class=fn>int <a href="#maxValue"><b>maxValue</b></a> () const</li> +<li class=fn>void <a href="#setRange"><b>setRange</b></a> ( int minValue, int maxValue )</li> +<li class=fn>void <a href="#setMinValue"><b>setMinValue</b></a> ( int minVal )</li> +<li class=fn>void <a href="#setMaxValue"><b>setMaxValue</b></a> ( int maxVal )</li> +<li class=fn>int <a href="#lineStep"><b>lineStep</b></a> () const</li> +<li class=fn>int <a href="#pageStep"><b>pageStep</b></a> () const</li> +<li class=fn>void <a href="#setSteps"><b>setSteps</b></a> ( int lineStep, int pageStep )</li> +<li class=fn>int <a href="#bound"><b>bound</b></a> ( int v ) const</li> +</ul> +<h2>Protected Members</h2> +<ul> +<li class=fn>int <a href="#positionFromValue"><b>positionFromValue</b></a> ( int logical_val, int span ) const</li> +<li class=fn>int <a href="#valueFromPosition"><b>valueFromPosition</b></a> ( int pos, int span ) const</li> +<li class=fn>void <a href="#directSetValue"><b>directSetValue</b></a> ( int value )</li> +<li class=fn>int <a href="#prevValue"><b>prevValue</b></a> () const</li> +<li class=fn>virtual void <a href="#valueChange"><b>valueChange</b></a> ()</li> +<li class=fn>virtual void <a href="#rangeChange"><b>rangeChange</b></a> ()</li> +<li class=fn>virtual void <a href="#stepChange"><b>stepChange</b></a> ()</li> +</ul> +<hr><a name="details"></a><h2>Detailed Description</h2> + + +The QRangeControl class provides an integer value within a range. +<p> +<p> Although originally designed for the <a href="qscrollbar.html">QScrollBar</a> widget, the +QRangeControl can also be used in conjunction with other widgets +such as <a href="qslider.html">QSlider</a> and <a href="qspinbox.html">QSpinBox</a>. Here are the five main concepts in +the class: +<p> <ol type=1> +<p> <li> <em>Current value</em> The bounded integer that +QRangeControl maintains. <a href="#value">value</a>() returns it, and several +functions, including <a href="#setValue">setValue</a>(), set it. +<p> <li> <em>Minimum</em> The lowest value that value() can ever +return. Returned by <a href="#minValue">minValue</a>() and set by <a href="#setRange">setRange</a>() or one of the +constructors. +<p> <li> <em>Maximum</em> The highest value that value() can ever +return. Returned by <a href="#maxValue">maxValue</a>() and set by setRange() or one of the +constructors. +<p> <li> <em>Line step</em> The smaller of two natural steps that +QRangeControl provides and typically corresponds to the user +pressing an arrow key. The line step is returned by <a href="#lineStep">lineStep</a>() +and set using <a href="#setSteps">setSteps</a>(). The functions <a href="#addLine">addLine</a>() and +<a href="#subtractLine">subtractLine</a>() respectively increment and decrement the current +value by lineStep(). +<p> <li> <em>Page step</em> The larger of two natural steps that +QRangeControl provides and typically corresponds to the user +pressing PageUp or PageDown. The page step is returned by +<a href="#pageStep">pageStep</a>() and set using setSteps(). The functions <a href="#addPage">addPage</a>() and +substractPage() respectively increment and decrement the current +value by pageStep(). +<p> </ol> +<p> Unity (1) may be viewed as a third step size. <a href="#setValue">setValue</a>() lets you +set the current value to any integer in the allowed range, not +just <a href="#minValue">minValue</a>() + <em>n</em> * lineStep() for integer values of <em>n</em>. +Some widgets may allow the user to set any value at all; others +may just provide multiples of lineStep() or pageStep(). +<p> QRangeControl provides three virtual functions that are well +suited for updating the on-screen representation of range controls +and emitting signals: <a href="#valueChange">valueChange</a>(), <a href="#rangeChange">rangeChange</a>() and +<a href="#stepChange">stepChange</a>(). +<p> QRangeControl also provides a function called <a href="#bound">bound</a>() which lets +you force arbitrary integers to be within the allowed range of the +range control. +<p> We recommend that all widgets that inherit QRangeControl provide +at least a signal called valueChanged(); many widgets will want to +provide addStep(), <a href="#addPage">addPage</a>(), substractStep() and substractPage() +as slots. +<p> Note that you must use multiple inheritance if you plan to +implement a widget using QRangeControl because QRangeControl is +not derived from <a href="qwidget.html">QWidget</a>. +<p>See also <a href="misc.html">Miscellaneous Classes</a>. + +<hr><h2>Member Function Documentation</h2> +<h3 class=fn><a name="QRangeControl"></a>QRangeControl::QRangeControl () +</h3> +Constructs a range control with a minimum value of 0, maximum +value of 99, line step of 1, page step of 10 and initial value 0. + +<h3 class=fn><a name="QRangeControl-2"></a>QRangeControl::QRangeControl ( int minValue, int maxValue, int lineStep, int pageStep, int value ) +</h3> +Constructs a range control whose value can never be smaller than +<em>minValue</em> or greater than <em>maxValue</em>, whose line step size is +<em>lineStep</em> and page step size is <em>pageStep</em> and whose value is +initially <em>value</em> (which is guaranteed to be in range using +<a href="#bound">bound</a>()). + +<h3 class=fn><a name="~QRangeControl"></a>QRangeControl::~QRangeControl ()<tt> [virtual]</tt> +</h3> +Destroys the range control + +<h3 class=fn>void <a name="addLine"></a>QRangeControl::addLine () +</h3> +Equivalent to <tt>setValue( value() + lineStep() )</tt>. +<p> If the value is changed, then <a href="#valueChange">valueChange</a>() is called. +<p> <p>See also <a href="#subtractLine">subtractLine</a>(), <a href="#addPage">addPage</a>(), and <a href="#setValue">setValue</a>(). + +<h3 class=fn>void <a name="addPage"></a>QRangeControl::addPage () +</h3> +Equivalent to <tt>setValue( value() + pageStep() )</tt>. +<p> If the value is changed, then <a href="#valueChange">valueChange</a>() is called. +<p> <p>See also <a href="#subtractPage">subtractPage</a>(), <a href="#addLine">addLine</a>(), and <a href="#setValue">setValue</a>(). + +<h3 class=fn>int <a name="bound"></a>QRangeControl::bound ( int v ) const +</h3> +Forces the value <em>v</em> to be within the range from <a href="#minValue">minValue</a>() to +<a href="#maxValue">maxValue</a>() inclusive, and returns the result. +<p> This function is provided so that you can easily force other +numbers than <a href="#value">value</a>() into the allowed range. You do not need to +call it in order to use QRangeControl itself. +<p> <p>See also <a href="#setValue">setValue</a>(), <a href="#value">value</a>(), <a href="#minValue">minValue</a>(), and <a href="#maxValue">maxValue</a>(). + +<h3 class=fn>void <a name="directSetValue"></a>QRangeControl::directSetValue ( int value )<tt> [protected]</tt> +</h3> +Sets the range control <em>value</em> directly without calling +<a href="#valueChange">valueChange</a>(). +<p> Forces the new <em>value</em> to be within the legal range. +<p> You will rarely have to call this function. However, if you want +to change the range control's value inside the overloaded method +valueChange(), <a href="#setValue">setValue</a>() would call the function valueChange() +again. To avoid this recursion you must use <a href="#directSetValue">directSetValue</a>() +instead. +<p> <p>See also <a href="#setValue">setValue</a>(). + +<h3 class=fn>int <a name="lineStep"></a>QRangeControl::lineStep () const +</h3> + +<p> Returns the line step. +<p> <p>See also <a href="#setSteps">setSteps</a>() and <a href="#pageStep">pageStep</a>(). + +<h3 class=fn>int <a name="maxValue"></a>QRangeControl::maxValue () const +</h3> + +<p> Returns the maximum value of the range. +<p> <p>See also <a href="#setMaxValue">setMaxValue</a>(), <a href="#setRange">setRange</a>(), and <a href="#minValue">minValue</a>(). + +<h3 class=fn>int <a name="minValue"></a>QRangeControl::minValue () const +</h3> + +<p> Returns the minimum value of the range. +<p> <p>See also <a href="#setMinValue">setMinValue</a>(), <a href="#setRange">setRange</a>(), and <a href="#maxValue">maxValue</a>(). + +<h3 class=fn>int <a name="pageStep"></a>QRangeControl::pageStep () const +</h3> + +<p> Returns the page step. +<p> <p>See also <a href="#setSteps">setSteps</a>() and <a href="#lineStep">lineStep</a>(). + +<h3 class=fn>int <a name="positionFromValue"></a>QRangeControl::positionFromValue ( int logical_val, int span ) const<tt> [protected]</tt> +</h3> +Converts <em>logical_val</em> to a pixel position. <a href="#minValue">minValue</a>() maps to 0, +<a href="#maxValue">maxValue</a>() maps to <em>span</em> and other values are distributed evenly +in-between. +<p> This function can handle the entire integer range without +overflow, providing <em>span</em> is <= 4096. +<p> Calling this method is useful when actually drawing a range +control such as a <a href="qscrollbar.html">QScrollBar</a> on-screen. +<p> <p>See also <a href="#valueFromPosition">valueFromPosition</a>(). + +<h3 class=fn>int <a name="prevValue"></a>QRangeControl::prevValue () const<tt> [protected]</tt> +</h3> + +<p> Returns the previous value of the range control. "Previous value" +means the value before the last change occurred. Setting a new +range may affect the value, too, because the value is forced to be +inside the specified range. When the range control is initially +created, this is the same as <a href="#value">value</a>(). +<p> <a href="#prevValue">prevValue</a>() can be outside the current legal range if a call to +<a href="#setRange">setRange</a>() causes the current value to change. For example, if the +range was [0, 1000] and the current value is 500, setRange(0, 400) +makes value() return 400 and prevValue() return 500. +<p> <p>See also <a href="#value">value</a>() and <a href="#setRange">setRange</a>(). + +<h3 class=fn>void <a name="rangeChange"></a>QRangeControl::rangeChange ()<tt> [virtual protected]</tt> +</h3> +This virtual function is called whenever the range control's range +changes. You can reimplement it if you want to be notified when +the range changes. The default implementation does nothing. +<p> Note that this method is called after the range has changed. +<p> <p>See also <a href="#setRange">setRange</a>(), <a href="#valueChange">valueChange</a>(), and <a href="#stepChange">stepChange</a>(). + +<p>Reimplemented in <a href="qdial.html#rangeChange">QDial</a>, <a href="qslider.html#rangeChange">QSlider</a>, and <a href="qspinbox.html#rangeChange">QSpinBox</a>. +<h3 class=fn>void <a name="setMaxValue"></a>QRangeControl::setMaxValue ( int maxVal ) +</h3> +Sets the minimum value of the range to <em>maxVal</em>. +<p> If necessary, the <a href="#minValue">minValue</a>() is adjusted so that the range remains +valid. +<p> <p>See also <a href="#maxValue">maxValue</a>() and <a href="#setMinValue">setMinValue</a>(). + +<h3 class=fn>void <a name="setMinValue"></a>QRangeControl::setMinValue ( int minVal ) +</h3> +Sets the minimum value of the range to <em>minVal</em>. +<p> If necessary, the <a href="#maxValue">maxValue</a>() is adjusted so that the range remains +valid. +<p> <p>See also <a href="#minValue">minValue</a>() and <a href="#setMaxValue">setMaxValue</a>(). + +<h3 class=fn>void <a name="setRange"></a>QRangeControl::setRange ( int minValue, int maxValue ) +</h3> +Sets the range control's minimum value to <em>minValue</em> and its +maximum value to <em>maxValue</em>. +<p> Calls the virtual <a href="#rangeChange">rangeChange</a>() function if one or both of the new +minimum and maximum values are different from the previous +setting. Calls the virtual <a href="#valueChange">valueChange</a>() function if the current +value is adjusted because it was outside the new range. +<p> If <em>maxValue</em> is smaller than <em>minValue</em>, <em>minValue</em> becomes +the only legal value. +<p> <p>See also <a href="#minValue">minValue</a>() and <a href="#maxValue">maxValue</a>(). + +<p>Examples: <a href="listbox-example.html#x1441">listbox/listbox.cpp</a>, <a href="tutorial1-12.html#x2387">t12/lcdrange.cpp</a>, <a href="tutorial1-05.html#x2315">t5/main.cpp</a>, <a href="tutorial1-06.html#x2325">t6/main.cpp</a>, <a href="tutorial1-08.html#x2334">t8/lcdrange.cpp</a>, and <a href="xform-example.html#x1250">xform/xform.cpp</a>. +<h3 class=fn>void <a name="setSteps"></a>QRangeControl::setSteps ( int lineStep, int pageStep ) +</h3> +Sets the range's line step to <em>lineStep</em> and page step to <em>pageStep</em>. +<p> Calls the virtual <a href="#stepChange">stepChange</a>() function if the new line step +or page step are different from the previous settings. +<p> <p>See also <a href="#lineStep">lineStep</a>(), <a href="#pageStep">pageStep</a>(), and <a href="#setRange">setRange</a>(). + +<h3 class=fn>void <a name="setValue"></a>QRangeControl::setValue ( int value ) +</h3> +Sets the range control's value to <em>value</em> and forces it to be +within the legal range. +<p> Calls the virtual <a href="#valueChange">valueChange</a>() function if the new value is +different from the previous value. The old value can still be +retrieved using <a href="#prevValue">prevValue</a>(). +<p> <p>See also <a href="#value">value</a>(). + +<h3 class=fn>void <a name="stepChange"></a>QRangeControl::stepChange ()<tt> [virtual protected]</tt> +</h3> +This virtual function is called whenever the range control's +line or page step settings change. You can reimplement it if you +want to be notified when the step changes. The default +implementation does nothing. +<p> Note that this method is called after a step setting has changed. +<p> <p>See also <a href="#setSteps">setSteps</a>(), <a href="#rangeChange">rangeChange</a>(), and <a href="#valueChange">valueChange</a>(). + +<h3 class=fn>void <a name="subtractLine"></a>QRangeControl::subtractLine () +</h3> +Equivalent to <tt>setValue( value() - lineStep() )</tt>. +<p> If the value is changed, then <a href="#valueChange">valueChange</a>() is called. +<p> <p>See also <a href="#addLine">addLine</a>(), <a href="#subtractPage">subtractPage</a>(), and <a href="#setValue">setValue</a>(). + +<h3 class=fn>void <a name="subtractPage"></a>QRangeControl::subtractPage () +</h3> +Equivalent to <tt>setValue( value() - pageStep() )</tt>. +<p> If the value is changed, then <a href="#valueChange">valueChange</a>() is called. +<p> <p>See also <a href="#addPage">addPage</a>(), <a href="#subtractLine">subtractLine</a>(), and <a href="#setValue">setValue</a>(). + +<h3 class=fn>int <a name="value"></a>QRangeControl::value () const +</h3> + +<p> Returns the current range control value. This is guaranteed to be +within the range [minValue(), <a href="#maxValue">maxValue</a>()]. +<p> <p>See also <a href="#setValue">setValue</a>() and <a href="#prevValue">prevValue</a>(). + +<h3 class=fn>void <a name="valueChange"></a>QRangeControl::valueChange ()<tt> [virtual protected]</tt> +</h3> +This virtual function is called whenever the range control value +changes. You can reimplement it if you want to be notified when +the value changes. The default implementation does nothing. +<p> Note that this method is called after the value has changed. The +previous value can be retrieved using <a href="#prevValue">prevValue</a>(). +<p> <p>See also <a href="#setValue">setValue</a>(), <a href="#addPage">addPage</a>(), <a href="#subtractPage">subtractPage</a>(), <a href="#addLine">addLine</a>(), <a href="#subtractLine">subtractLine</a>(), <a href="#rangeChange">rangeChange</a>(), and <a href="#stepChange">stepChange</a>(). + +<p>Reimplemented in <a href="qdial.html#valueChange">QDial</a>, <a href="qslider.html#valueChange">QSlider</a>, and <a href="qspinbox.html#valueChange">QSpinBox</a>. +<h3 class=fn>int <a name="valueFromPosition"></a>QRangeControl::valueFromPosition ( int pos, int span ) const<tt> [protected]</tt> +</h3> +Converts the pixel position <em>pos</em> to a value. 0 maps to +<a href="#minValue">minValue</a>(), <em>span</em> maps to <a href="#maxValue">maxValue</a>() and other values are +distributed evenly in-between. +<p> This function can handle the entire integer range without +overflow. +<p> Calling this method is useful if you actually implemented a range +control widget such as <a href="qscrollbar.html">QScrollBar</a> and want to handle mouse press +events. This function then maps screen coordinates to the logical +values. +<p> <p>See also <a href="#positionFromValue">positionFromValue</a>(). + +<!-- eof --> +<hr><p> +This file is part of the <a href="index.html">Qt toolkit</a>. +Copyright © 1995-2007 +<a href="http://www.trolltech.com/">Trolltech</a>. All Rights Reserved.<p><address><hr><div align=center> +<table width=100% cellspacing=0 border=0><tr> +<td>Copyright © 2007 +<a href="troll.html">Trolltech</a><td align=center><a href="trademarks.html">Trademarks</a> +<td align=right><div align=right>Qt 3.3.8</div> +</table></div></address></body> +</html> |