<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
<!-- /tmp/qt-3.0-reggie-28534/qt-x11-free-3.0.2/src/canvas/qcanvas.cpp:1728 -->
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>QCanvasItem Class</title>
<style type="text/css"><!--
h3.fn,span.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>QCanvasItem Class Reference<br><small>[<a href="canvas.html">canvas module</a>]</small></h1>
<p>The QCanvasItem class provides an abstract graphic object on a QCanvas.
<a href="#details">More...</a>
<p><tt>#include <<a href="qcanvas-h.html">qcanvas.h</a>></tt>
<p>Inherits <a href="qt.html">Qt</a>.
<p>Inherited by <a href="qcanvassprite.html">QCanvasSprite</a>, <a href="qcanvaspolygonalitem.html">QCanvasPolygonalItem</a> and <a href="qcanvastext.html">QCanvasText</a>.
<p><a href="qcanvasitem-members.html">List of all member functions.</a>
<h2>Public Members</h2>
<ul>
<li><div class=fn><a href="#QCanvasItem"><b>QCanvasItem</b></a> ( QCanvas * canvas )</div></li>
<li><div class=fn>virtual <a href="#~QCanvasItem"><b>~QCanvasItem</b></a> ()</div></li>
<li><div class=fn>double <a href="#x"><b>x</b></a> () const</div></li>
<li><div class=fn>double <a href="#y"><b>y</b></a> () const</div></li>
<li><div class=fn>double <a href="#z"><b>z</b></a> () const</div></li>
<li><div class=fn>virtual void <a href="#moveBy"><b>moveBy</b></a> ( double dx, double dy )</div></li>
<li><div class=fn>void <a href="#move"><b>move</b></a> ( double x, double y )</div></li>
<li><div class=fn>void <a href="#setX"><b>setX</b></a> ( double x )</div></li>
<li><div class=fn>void <a href="#setY"><b>setY</b></a> ( double y )</div></li>
<li><div class=fn>void <a href="#setZ"><b>setZ</b></a> ( double z )</div></li>
<li><div class=fn>bool <a href="#animated"><b>animated</b></a> () const</div></li>
<li><div class=fn>virtual void <a href="#setAnimated"><b>setAnimated</b></a> ( bool y )</div></li>
<li><div class=fn>virtual void <a href="#setVelocity"><b>setVelocity</b></a> ( double vx, double vy )</div></li>
<li><div class=fn>void <a href="#setXVelocity"><b>setXVelocity</b></a> ( double vx )</div></li>
<li><div class=fn>void <a href="#setYVelocity"><b>setYVelocity</b></a> ( double vy )</div></li>
<li><div class=fn>double <a href="#xVelocity"><b>xVelocity</b></a> () const</div></li>
<li><div class=fn>double <a href="#yVelocity"><b>yVelocity</b></a> () const</div></li>
<li><div class=fn>virtual void <a href="#advance"><b>advance</b></a> ( int phase )</div></li>
<li><div class=fn>virtual bool <a href="#collidesWith"><b>collidesWith</b></a> ( const QCanvasItem * other ) const = 0</div></li>
<li><div class=fn>QCanvasItemList <a href="#collisions"><b>collisions</b></a> ( bool exact ) const</div></li>
<li><div class=fn>virtual void <a href="#setCanvas"><b>setCanvas</b></a> ( QCanvas * c )</div></li>
<li><div class=fn>virtual void <a href="#draw"><b>draw</b></a> ( QPainter & painter ) = 0</div></li>
<li><div class=fn>void <a href="#show"><b>show</b></a> ()</div></li>
<li><div class=fn>void <a href="#hide"><b>hide</b></a> ()</div></li>
<li><div class=fn>virtual void <a href="#setVisible"><b>setVisible</b></a> ( bool yes )</div></li>
<li><div class=fn>bool <a href="#isVisible"><b>isVisible</b></a> () const</div></li>
<li><div class=fn>virtual void <a href="#setSelected"><b>setSelected</b></a> ( bool yes )</div></li>
<li><div class=fn>bool <a href="#isSelected"><b>isSelected</b></a> () const</div></li>
<li><div class=fn>virtual void <a href="#setEnabled"><b>setEnabled</b></a> ( bool yes )</div></li>
<li><div class=fn>bool <a href="#isEnabled"><b>isEnabled</b></a> () const</div></li>
<li><div class=fn>virtual void <a href="#setActive"><b>setActive</b></a> ( bool yes )</div></li>
<li><div class=fn>bool <a href="#isActive"><b>isActive</b></a> () const</div></li>
<li><div class=fn>bool visible () const <em>(obsolete)</em></div></li>
<li><div class=fn>bool selected () const <em>(obsolete)</em></div></li>
<li><div class=fn>bool enabled () const <em>(obsolete)</em></div></li>
<li><div class=fn>bool active () const <em>(obsolete)</em></div></li>
<li><div class=fn>enum <a href="#RttiValues-enum"><b>RttiValues</b></a> { Rtti_Item = 0, Rtti_Sprite = 1, Rtti_PolygonalItem = 2, Rtti_Text = 3, Rtti_Polygon = 4, Rtti_Rectangle = 5, Rtti_Ellipse = 6, Rtti_Line = 7, Rtti_Spline = 8 }</div></li>
<li><div class=fn>virtual int <a href="#rtti"><b>rtti</b></a> () const</div></li>
<li><div class=fn>virtual QRect <a href="#boundingRect"><b>boundingRect</b></a> () const = 0</div></li>
<li><div class=fn>virtual QRect <a href="#boundingRectAdvanced"><b>boundingRectAdvanced</b></a> () const</div></li>
<li><div class=fn>QCanvas * <a href="#canvas"><b>canvas</b></a> () const</div></li>
</ul>
<h2>Protected Members</h2>
<ul>
<li><div class=fn>void <a href="#update"><b>update</b></a> ()</div></li>
</ul>
<hr><a name="details"></a><h2>Detailed Description</h2>
The QCanvasItem class provides an abstract graphic object on a <a href="qcanvas.html">QCanvas</a>.
<p> A variety of subclasses provide immediately usable behaviour; this class
is a pure abstract superclass providing the behaviour that is shared
among all the concrete canvas item classes. QCanvasItem is not intended
for direct subclassing. It is much easier to subclass one of its
subclasses, e.g. <a href="qcanvaspolygonalitem.html">QCanvasPolygonalItem</a> (the commonest base class),
<a href="qcanvasrectangle.html">QCanvasRectangle</a>, <a href="qcanvassprite.html">QCanvasSprite</a>, <a href="qcanvasellipse.html">QCanvasEllipse</a> or <a href="qcanvastext.html">QCanvasText</a>.
<p> Canvas items are added to a canvas by constructing them and passing the
canvas to the canvas item's constructor. An item can be moved to a
different canvas using <a href="#setCanvas">setCanvas</a>().
<p> A QCanvasItem object can be moved in the <a href="#x">x</a>(), <a href="#y">y</a>() and <a href="#z">z</a>() dimensions
using functions such as <a href="#move">move</a>(), <a href="#moveBy">moveBy</a>(), <a href="#setX">setX</a>(), <a href="#setY">setY</a>() and <a href="#setZ">setZ</a>(). A
canvas item can be set in motion, `animated', using <a href="#setAnimated">setAnimated</a>() and
given a velocity in the x and y directions with <a href="#setXVelocity">setXVelocity</a>() and
<a href="#setYVelocity">setYVelocity</a>() -- the same effect can be achieved by calling
<a href="#setVelocity">setVelocity</a>(). Use the <a href="#collidesWith">collidesWith</a>() function to see if the canvas item
will collide on the <em>next</em> <a href="#advance">advance</a>(1) and use <a href="#collisions">collisions</a>() to see what
collisions have occurred.
<p> Use <a href="qcanvassprite.html">QCanvasSprite</a> or your own subclass of QCanvasSprite to create canvas
items which are animated, i.e. which change over time.
<p> The size of a canvas item is given by <a href="#boundingRect">boundingRect</a>(). Use
<a href="#boundingRectAdvanced">boundingRectAdvanced</a>() to see what the size of the canvas item will be
<em>after</em> the next advance(1) call.
<p> The <a href="#rtti">rtti</a>() function is used for identifying subclasses of QCanvasItem.
The <a href="#canvas">canvas</a>() function returns a pointer to the canvas which contains the
canvas item.
<p> QCanvasItem provides the <a href="#show">show</a>() and <a href="#isVisible">isVisible</a>() functions like those in
<a href="qwidget.html">QWidget</a>.
<p> QCanvasItem also provides the <a href="#setEnabled">setEnabled</a>(), <a href="#setActive">setActive</a>() and
<a href="#setSelected">setSelected</a>() functions; these functions set the relevant boolean and
cause a repaint but the boolean values they set are not used in
QCanvasItem itself. You can make use of these booleans in your subclasses.
<p> By default canvas items have no velocity, no size and are not in motion.
The subclasses provided in Qt do not change these defaults except where
noted.
<p> <p>See also <a href="graphics.html">Graphics Classes</a> and <a href="images.html">Image Processing Classes</a>.
<hr><h2>Member Type Documentation</h2>
<h3 class=fn><a name="RttiValues-enum"></a>QCanvasItem::RttiValues</h3>
<p> This enum is used to name the different types of canvas item.
<ul>
<li><tt>QCanvasItem::Rtti_Item</tt> - Canvas item abstract base class
<li><tt>QCanvasItem::Rtti_Ellipse</tt>
<li><tt>QCanvasItem::Rtti_Line</tt>
<li><tt>QCanvasItem::Rtti_Polygon</tt>
<li><tt>QCanvasItem::Rtti_PolygonalItem</tt>
<li><tt>QCanvasItem::Rtti_Rectangle</tt>
<li><tt>QCanvasItem::Rtti_Spline</tt>
<li><tt>QCanvasItem::Rtti_Sprite</tt>
<li><tt>QCanvasItem::Rtti_Text</tt>
</ul><p>
<hr><h2>Member Function Documentation</h2>
<h3 class=fn><a name="QCanvasItem"></a>QCanvasItem::QCanvasItem ( <a href="qcanvas.html">QCanvas</a> * canvas )
</h3>
Constructs a QCanvasItem on canvas <em>canvas</em>.
<p> <p>See also <a href="#setCanvas">setCanvas</a>().
<h3 class=fn><a name="~QCanvasItem"></a>QCanvasItem::~QCanvasItem ()<tt> [virtual]</tt>
</h3>
Destroys the QCanvasItem and removes it from its canvas.
<h3 class=fn>bool <a name="active"></a>QCanvasItem::active () const
</h3>
<b>This function is obsolete.</b> It is provided to keep old source working. We strongly advise against using it in new code.
<p>
Use <a href="#isActive">isActive</a>() instead.
<h3 class=fn>void <a name="advance"></a>QCanvasItem::advance ( int phase )<tt> [virtual]</tt>
</h3> The default implementation moves the canvas item, if it is
<a href="#animated">animated</a>(), by the preset velocity if <em>phase</em> is 1, and does nothing
if <em>phase</em> is 0.
<p> Note that if you reimplement this function, the reimplementation must
not change the canvas in any way, for example it must not add or remove
items.
<p> <p>See also <a href="qcanvas.html#advance">QCanvas::advance</a>() and <a href="#setVelocity">setVelocity</a>().
<p>Example: <a href="canvas-example.html#x2513">canvas/canvas.cpp</a>.
<p>Reimplemented in <a href="qcanvassprite.html#advance">QCanvasSprite</a>.
<h3 class=fn>bool <a name="animated"></a>QCanvasItem::animated () const
</h3> Returns TRUE is the canvas item is in motion; otherwise
returns FALSE.
<p> <p>See also <a href="#setVelocity">setVelocity</a>() and <a href="#setAnimated">setAnimated</a>().
<h3 class=fn><a href="qrect.html">QRect</a> <a name="boundingRect"></a>QCanvasItem::boundingRect () const<tt> [pure virtual]</tt>
</h3>
<p> Returns the bounding rectangle in pixels that the canvas item covers.
<p> <p>See also <a href="#boundingRectAdvanced">boundingRectAdvanced</a>().
<p>Reimplemented in <a href="qcanvassprite.html#boundingRect">QCanvasSprite</a>, <a href="qcanvaspolygonalitem.html#boundingRect">QCanvasPolygonalItem</a> and <a href="qcanvastext.html#boundingRect">QCanvasText</a>.
<h3 class=fn><a href="qrect.html">QRect</a> <a name="boundingRectAdvanced"></a>QCanvasItem::boundingRectAdvanced () const<tt> [virtual]</tt>
</h3>
Returns the bounding rectangle of pixels that the canvas item <em>will</em>
cover after <a href="#advance">advance</a>(1) is called.
<p> <p>See also <a href="#boundingRect">boundingRect</a>().
<h3 class=fn><a href="qcanvas.html">QCanvas</a> * <a name="canvas"></a>QCanvasItem::canvas () const
</h3>
<p> Returns the canvas containing the canvas item.
<h3 class=fn>bool <a name="collidesWith"></a>QCanvasItem::collidesWith ( const <a href="qcanvasitem.html">QCanvasItem</a> * other ) const<tt> [pure virtual]</tt>
</h3>
<p> Returns TRUE if the canvas item will collide with the <em>other</em> item <em>after</em> they have moved by their current velocities; otherwise returns
FALSE.
<p> <p>See also <a href="#collisions">collisions</a>().
<p>Example: <a href="canvas-example.html#x2514">canvas/canvas.cpp</a>.
<h3 class=fn><a href="qcanvasitemlist.html">QCanvasItemList</a> <a name="collisions"></a>QCanvasItem::collisions ( bool exact ) const
</h3>
Returns the list of canvas items that this canvas item has collided
with.
<p> A collision is generally defined as pixels of one item drawing on the
pixels of another item, but not all subclasses are so precise. Also,
since pixel-wise collision detection can be slow, this function
works in either exact or inexact mode, according to the <em>exact</em>
parameter.
<p> If <em>exact</em> is TRUE, the canvas items returned have been accurately
tested for collision with the canvas item.
<p> If <em>exact</em> is FALSE, the canvas items returned are <em>near</em> the canvas
item. You can test the canvas items returned using <a href="#collidesWith">collidesWith</a>() if
any are interesting collision candidates. By using this approach, you
can ignore some canvas items for which collisions are not relevant.
<p> The returned list is a list of QCanvasItems, but often you will need
to cast the items to their subclass types. The safe way to do this is
to use <a href="#rtti">rtti</a>() before casting. This provides some of the functionality
of the standard C++ dynamic cast operation even on compilers where
dynamic casts are not available.
<p> Note that a canvas item may be `on' a canvas, e.g. it was created
with the canvas as parameter, even though its coordinates place it
beyond the edge of the canvas's area. Collision detection only works
for canvas items which are wholly or partly within the canvas's
area.
<h3 class=fn>void <a name="draw"></a>QCanvasItem::draw ( <a href="qpainter.html">QPainter</a> & painter )<tt> [pure virtual]</tt>
</h3>
<p> This abstract virtual function draws the canvas item using <em>painter</em>.
<p>Reimplemented in <a href="qcanvassprite.html#draw">QCanvasSprite</a>, <a href="qcanvaspolygonalitem.html#draw">QCanvasPolygonalItem</a> and <a href="qcanvastext.html#draw">QCanvasText</a>.
<h3 class=fn>bool <a name="enabled"></a>QCanvasItem::enabled () const
</h3>
<b>This function is obsolete.</b> It is provided to keep old source working. We strongly advise against using it in new code.
<p>
Use <a href="#isEnabled">isEnabled</a>() instead.
<h3 class=fn>void <a name="hide"></a>QCanvasItem::hide ()
</h3> Shorthand for <a href="#setVisible">setVisible</a>(FALSE).
<h3 class=fn>bool <a name="isActive"></a>QCanvasItem::isActive () const
</h3>
Returns TRUE if the QCanvasItem is active; otherwise returns FALSE.
<h3 class=fn>bool <a name="isEnabled"></a>QCanvasItem::isEnabled () const
</h3>
Returns TRUE if the QCanvasItem is enabled; otherwise returns FALSE.
<h3 class=fn>bool <a name="isSelected"></a>QCanvasItem::isSelected () const
</h3>
<p> Returns TRUE if the canvas item is selected; otherwise returns FALSE.
<h3 class=fn>bool <a name="isVisible"></a>QCanvasItem::isVisible () const
</h3>
<p> Returns TRUE if the canvas item is visible otherwise returns FALSE.
<p> Note that in this context TRUE does <em>not</em> mean that the canvas item
is currently in a view, merely that if a view is showing the area
where the canvas item is positioned, and the item is not obscured by
items with higher z values, and the view is not obscured by overlaying
windows, it would be visible.
<p> <p>See also <a href="#setVisible">setVisible</a>() and <a href="#z">z</a>().
<h3 class=fn>void <a name="move"></a>QCanvasItem::move ( double x, double y )
</h3> Moves the canvas item to the absolute position (<em>x</em>, <em>y</em>).
<p>Example: <a href="canvas-example.html#x2515">canvas/canvas.cpp</a>.
<h3 class=fn>void <a name="moveBy"></a>QCanvasItem::moveBy ( double dx, double dy )<tt> [virtual]</tt>
</h3> Moves the canvas item relative to its current position
by (<em>dx</em>, <em>dy</em>).
<p>Example: <a href="canvas-example.html#x2516">canvas/canvas.cpp</a>.
<h3 class=fn>int <a name="rtti"></a>QCanvasItem::rtti () const<tt> [virtual]</tt>
</h3>
Returns 0 (QCanvasItem::Rtti_Item).
<p> Although often frowned upon by purists, Run Time
Type Identification is very useful in these classes as it allows
a <a href="qcanvas.html">QCanvas</a> to be an efficient indexed storage mechanism.
<p> Make your derived classes return their own values for <a href="#rtti">rtti</a>(), so that you
can distinguish between objects returned by QCanvas::at(). You should
use values greater than 1000 to allow extensions to this class.
<p> Overuse of this functionality can damage it's extensibility.
For example, once you have identified a base class of a QCanvasItem
found by QCanvas::at(), cast it to that type and call meaningful
methods rather than acting upon the object based on its rtti value.
<p> For example:
<p> <pre>
QCanvasItem* item;
// Find an item, eg. with QCanvasItem::collisions().
...
if (item-><a href="#rtti">rtti</a>() == MySprite::RTTI ) {
MySprite* s = (MySprite*)item;
if (s->isDamagable()) s->loseHitPoints(1000);
if (s->isHot()) myself->loseHitPoints(1000);
...
}
</pre>
<p>Example: <a href="canvas-example.html#x2517">canvas/canvas.cpp</a>.
<p>Reimplemented in <a href="qcanvassprite.html#rtti">QCanvasSprite</a>, <a href="qcanvaspolygonalitem.html#rtti">QCanvasPolygonalItem</a> and <a href="qcanvastext.html#rtti">QCanvasText</a>.
<h3 class=fn>bool <a name="selected"></a>QCanvasItem::selected () const
</h3>
<b>This function is obsolete.</b> It is provided to keep old source working. We strongly advise against using it in new code.
<p>
Use <a href="#isSelected">isSelected</a>() instead.
<h3 class=fn>void <a name="setActive"></a>QCanvasItem::setActive ( bool yes )<tt> [virtual]</tt>
</h3> Sets the active flag of the item to <em>yes</em> and causes it to be
redrawn when <a href="qcanvas.html#update">QCanvas::update</a>() is next called.
<p> The <a href="qcanvas.html">QCanvas</a>, QCanvasItem and the Qt-supplied QCanvasItem subclasses do
not make use of this value. The <a href="#setActive">setActive</a>() function is supplied
because many applications need it, but it is up to you how you use the
<a href="#isActive">isActive</a>() value.
<h3 class=fn>void <a name="setAnimated"></a>QCanvasItem::setAnimated ( bool y )<tt> [virtual]</tt>
</h3> Sets the canvas item to be in motion if <em>y</em> is TRUE, or
not if <em>y</em> is FALSE. The speed and direction of the motion is set with
<a href="#setVelocity">setVelocity</a>(), or <a href="#setXVelocity">setXVelocity</a>() and <a href="#setYVelocity">setYVelocity</a>().
<p> <p>See also <a href="#advance">advance</a>() and <a href="qcanvas.html#advance">QCanvas::advance</a>().
<h3 class=fn>void <a name="setCanvas"></a>QCanvasItem::setCanvas ( <a href="qcanvas.html">QCanvas</a> * c )<tt> [virtual]</tt>
</h3> Sets the <a href="qcanvas.html">QCanvas</a> upon which the canvas item is to be drawn to <em>c</em>.
<p> <p>See also <a href="#canvas">canvas</a>().
<h3 class=fn>void <a name="setEnabled"></a>QCanvasItem::setEnabled ( bool yes )<tt> [virtual]</tt>
</h3> Sets the enabled flag of the item to <em>yes</em> and causes it to be
redrawn when <a href="qcanvas.html#update">QCanvas::update</a>() is next called.
<p> The <a href="qcanvas.html">QCanvas</a>, QCanvasItem and the Qt-supplied QCanvasItem subclasses do
not make use of this value. The <a href="#setEnabled">setEnabled</a>() function is supplied
because many applications need it, but it is up to you how you use the
<a href="#isEnabled">isEnabled</a>() value.
<h3 class=fn>void <a name="setSelected"></a>QCanvasItem::setSelected ( bool yes )<tt> [virtual]</tt>
</h3> Sets the selected flag of the item to <em>yes</em> and causes it to be
redrawn when <a href="qcanvas.html#update">QCanvas::update</a>() is next called.
<p> The <a href="qcanvas.html">QCanvas</a>, QCanvasItem and the Qt-supplied QCanvasItem subclasses do
not make use of this value. The <a href="#setSelected">setSelected</a>() function is supplied
because many applications need it, but it is up to you how you use the
<a href="#isSelected">isSelected</a>() value.
<h3 class=fn>void <a name="setVelocity"></a>QCanvasItem::setVelocity ( double vx, double vy )<tt> [virtual]</tt>
</h3> Sets the canvas item to be in motion, moving
by <em>vx</em> and <em>vy</em> pixels in the horizontal and vertical directions
respectively.
<p> <p>See also <a href="#advance">advance</a>().
<h3 class=fn>void <a name="setVisible"></a>QCanvasItem::setVisible ( bool yes )<tt> [virtual]</tt>
</h3> Makes the canvas item visible if <em>yes</em> is TRUE, or invisible if <em>yes</em> is FALSE. The change takes effect when <a href="qcanvas.html#update">QCanvas::update</a>() is next
called.
<h3 class=fn>void <a name="setX"></a>QCanvasItem::setX ( double x )
</h3>
<p> Moves the canvas item so that its x-position is <em>x</em>.
<p>See also <a href="#x">x</a>() and <a href="#move">move</a>().
<h3 class=fn>void <a name="setXVelocity"></a>QCanvasItem::setXVelocity ( double vx )
</h3>
<p> Sets the horizontal component of the canvas item's velocity to <em>vx</em>.
<h3 class=fn>void <a name="setY"></a>QCanvasItem::setY ( double y )
</h3>
<p> Moves the canvas item so that its y-position is <em>y</em>.
<p>See also <a href="#y">y</a>() and <a href="#move">move</a>().
<h3 class=fn>void <a name="setYVelocity"></a>QCanvasItem::setYVelocity ( double vy )
</h3>
<p> Sets the vertical component of the canvas item's velocity to <em>vy</em>.
<h3 class=fn>void <a name="setZ"></a>QCanvasItem::setZ ( double z )
</h3>
<p> Sets the z index of the canvas item to <em>z</em>. Higher-z items obscure
(are in front of) lower-z items.
<p> <p>See also <a href="#z">z</a>() and <a href="#move">move</a>().
<p>Example: <a href="canvas-example.html#x2518">canvas/canvas.cpp</a>.
<h3 class=fn>void <a name="show"></a>QCanvasItem::show ()
</h3> Shorthand for <a href="#setVisible">setVisible</a>(TRUE).
<p>Example: <a href="canvas-example.html#x2519">canvas/canvas.cpp</a>.
<h3 class=fn>void <a name="update"></a>QCanvasItem::update ()<tt> [protected]</tt>
</h3>
<p> Call this function to repaint the canvas's changed chunks.
<h3 class=fn>bool <a name="visible"></a>QCanvasItem::visible () const
</h3>
<b>This function is obsolete.</b> It is provided to keep old source working. We strongly advise against using it in new code.
<p>
Use <a href="#isVisible">isVisible</a>() instead.
<h3 class=fn>double <a name="x"></a>QCanvasItem::x () const
</h3>
<p> Returns the horizontal position of the canvas item. Note that
subclasses often have an origin other than the top-left corner.
<p>Example: <a href="canvas-example.html#x2520">canvas/canvas.cpp</a>.
<h3 class=fn>double <a name="xVelocity"></a>QCanvasItem::xVelocity () const
</h3>
Returns the horizontal velocity component of the canvas item.
<h3 class=fn>double <a name="y"></a>QCanvasItem::y () const
</h3>
<p> Returns the vertical position of the canvas item. Note that
subclasses often have an origin other than the top-left corner.
<p>Example: <a href="canvas-example.html#x2521">canvas/canvas.cpp</a>.
<h3 class=fn>double <a name="yVelocity"></a>QCanvasItem::yVelocity () const
</h3>
Returns the vertical velocity component of the canvas item.
<h3 class=fn>double <a name="z"></a>QCanvasItem::z () const
</h3>
<p> Returns the z index of the canvas item, which is used for visual
order: higher-z items obscure (are in front of) lower-z items.
<!-- eof -->
<hr><p>
This file is part of the <a href="index.html">Qt toolkit</a>.
Copyright © 1995-2001
<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 © 2001
<a href="http://www.trolltech.com">Trolltech</a><td><a href="http://www.trolltech.com/trademarks.html">Trademarks</a>
<td align=right><div align=right>Qt version 3.0.2</div>
</table></div></address></body>
</html>
distrib
>
Mandriva
>
8.2
>
i586
>
media
>
contrib
>
by-pkgid
>
112b0974ad288f6cd55bf971ee6026a9
>
files
>
920
