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diff --git a/doc/html/qcanvasitem.html b/doc/html/qcanvasitem.html new file mode 100644 index 0000000..1edfee5 --- /dev/null +++ b/doc/html/qcanvasitem.html @@ -0,0 +1,480 @@ +<!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/canvas/qcanvas.cpp:1843 --> +<html> +<head> +<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1"> +<title>QCanvasItem 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>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 class=fn><a href="#QCanvasItem"><b>QCanvasItem</b></a> ( QCanvas * canvas )</li> +<li class=fn>virtual <a href="#~QCanvasItem"><b>~QCanvasItem</b></a> ()</li> +<li class=fn>double <a href="#x"><b>x</b></a> () const</li> +<li class=fn>double <a href="#y"><b>y</b></a> () const</li> +<li class=fn>double <a href="#z"><b>z</b></a> () const</li> +<li class=fn>virtual void <a href="#moveBy"><b>moveBy</b></a> ( double dx, double dy )</li> +<li class=fn>void <a href="#move"><b>move</b></a> ( double x, double y )</li> +<li class=fn>void <a href="#setX"><b>setX</b></a> ( double x )</li> +<li class=fn>void <a href="#setY"><b>setY</b></a> ( double y )</li> +<li class=fn>void <a href="#setZ"><b>setZ</b></a> ( double z )</li> +<li class=fn>bool <a href="#animated"><b>animated</b></a> () const</li> +<li class=fn>virtual void <a href="#setAnimated"><b>setAnimated</b></a> ( bool y )</li> +<li class=fn>virtual void <a href="#setVelocity"><b>setVelocity</b></a> ( double vx, double vy )</li> +<li class=fn>void <a href="#setXVelocity"><b>setXVelocity</b></a> ( double vx )</li> +<li class=fn>void <a href="#setYVelocity"><b>setYVelocity</b></a> ( double vy )</li> +<li class=fn>double <a href="#xVelocity"><b>xVelocity</b></a> () const</li> +<li class=fn>double <a href="#yVelocity"><b>yVelocity</b></a> () const</li> +<li class=fn>virtual void <a href="#advance"><b>advance</b></a> ( int phase )</li> +<li class=fn>virtual bool <a href="#collidesWith"><b>collidesWith</b></a> ( const QCanvasItem * other ) const = 0</li> +<li class=fn>QCanvasItemList <a href="#collisions"><b>collisions</b></a> ( bool exact ) const</li> +<li class=fn>virtual void <a href="#setCanvas"><b>setCanvas</b></a> ( QCanvas * c )</li> +<li class=fn>virtual void <a href="#draw"><b>draw</b></a> ( QPainter & painter ) = 0</li> +<li class=fn>void <a href="#show"><b>show</b></a> ()</li> +<li class=fn>void <a href="#hide"><b>hide</b></a> ()</li> +<li class=fn>virtual void <a href="#setVisible"><b>setVisible</b></a> ( bool yes )</li> +<li class=fn>bool <a href="#isVisible"><b>isVisible</b></a> () const</li> +<li class=fn>virtual void <a href="#setSelected"><b>setSelected</b></a> ( bool yes )</li> +<li class=fn>bool <a href="#isSelected"><b>isSelected</b></a> () const</li> +<li class=fn>virtual void <a href="#setEnabled"><b>setEnabled</b></a> ( bool yes )</li> +<li class=fn>bool <a href="#isEnabled"><b>isEnabled</b></a> () const</li> +<li class=fn>virtual void <a href="#setActive"><b>setActive</b></a> ( bool yes )</li> +<li class=fn>bool <a href="#isActive"><b>isActive</b></a> () const</li> +<li class=fn>bool visible () const <em>(obsolete)</em></li> +<li class=fn>bool selected () const <em>(obsolete)</em></li> +<li class=fn>bool enabled () const <em>(obsolete)</em></li> +<li class=fn>bool active () const <em>(obsolete)</em></li> +<li 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 }</li> +<li class=fn>virtual int <a href="#rtti"><b>rtti</b></a> () const</li> +<li class=fn>virtual QRect <a href="#boundingRect"><b>boundingRect</b></a> () const = 0</li> +<li class=fn>virtual QRect <a href="#boundingRectAdvanced"><b>boundingRectAdvanced</b></a> () const</li> +<li class=fn>QCanvas * <a href="#canvas"><b>canvas</b></a> () const</li> +</ul> +<h2>Protected Members</h2> +<ul> +<li class=fn>void <a href="#update"><b>update</b></a> ()</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> + + +<p> A variety of QCanvasItem 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> Items appear on the canvas after their <a href="#show">show()</a> +function has been called (or <a href="#setVisible">setVisible(TRUE)</a>), and <em>after</em> <a href="#update">update</a>() has been called. The +canvas only shows items that are <a href="#setVisible">visible</a>, +and then only if <a href="#update">update</a>() is called. If you created the canvas +without passing a width and height to the constructor you'll also need +to call <a href="qcanvas.html#resize">resize()</a>. Since the canvas +background defaults to white and canvas items default to white, +you may need to change colors to see your items. +<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#x2913">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 if 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#x2914">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 occurring when the pixels of +one item draw 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. +<p> Note that if items have a velocity (see <a href="#setVelocity">setVelocity</a>()), then +collision testing is done based on where the item <em>will</em> be when +it moves, not its current location. For example, a "ball" item +doesn't need to actually embed into a "wall" item before a +collision is detected. For items without velocity, plain +intersection is used. + +<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> <b>Warning:</b> When you reimplement this function, make sure that you +leave the painter in the same state as you found it. For example, +if you start by calling <a href="qpainter.html#translate">QPainter::translate</a>(50, 50), end your +code by calling QPainter::translate(-50, -50). Be also aware that +the painter might already have some transformations set (i.e., +don't call <a href="qpainter.html#resetXForm">QPainter::resetXForm</a>() when you're done). + +<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> + +<p> Returns TRUE if the QCanvasItem is active; otherwise returns FALSE. + +<h3 class=fn>bool <a name="isEnabled"></a>QCanvasItem::isEnabled () const +</h3> + +<p> 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#x2915">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#x2916">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> 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 +for 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, e.g. 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#x2917">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>. If this changes the +item's active state the item will 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 with <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>. If this changes the +item's enabled state the item will 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>. If this changes the +item's selected state the item will 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>(), <a href="#setXVelocity">setXVelocity</a>(), and <a href="#setYVelocity">setYVelocity</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> <p>See also <a href="#x">x</a>() and <a href="#move">move</a>(). + +<p>Example: <a href="tutorial2-06.html#x2568">chart/chartform_canvas.cpp</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>. +<p> <p>See also <a href="#setYVelocity">setYVelocity</a>() and <a href="#setVelocity">setVelocity</a>(). + +<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> <p>See also <a href="#y">y</a>() and <a href="#move">move</a>(). + +<p>Example: <a href="tutorial2-06.html#x2569">chart/chartform_canvas.cpp</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>. +<p> <p>See also <a href="#setXVelocity">setXVelocity</a>() and <a href="#setVelocity">setVelocity</a>(). + +<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>Examples: <a href="canvas-example.html#x2918">canvas/canvas.cpp</a> and <a href="tutorial2-06.html#x2570">chart/chartform_canvas.cpp</a>. +<h3 class=fn>void <a name="show"></a>QCanvasItem::show () +</h3> Shorthand for <a href="#setVisible">setVisible</a>(TRUE). +<p>Examples: <a href="canvas-example.html#x2919">canvas/canvas.cpp</a> and <a href="tutorial2-06.html#x2571">chart/chartform_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#x2920">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#x2921">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 © 1995-2007 +<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> |