diff -r 892c1787d666 -r edde1fe80b3e Documentation/Source/eric5.Graphics.AssociationItem.html --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/Documentation/Source/eric5.Graphics.AssociationItem.html Sat Jan 02 18:19:35 2010 +0000 @@ -0,0 +1,281 @@ +<?xml version="1.0" encoding="utf-8"?> +<!DOCTYPE html PUBLIC '-//W3C//DTD XHTML 1.0 Strict//EN' +'http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd'> +<html><head> +<title>eric5.Graphics.AssociationItem</title> +<style> +b'body {\n background:white;\n margin: 0em 1em 10em 1em;\n color: black;\n}\n\nh1 { color: white; background: #4FA4FF; }\nh2 { color: white; background: #4FA4FF; }\nh3 { color: white; background: #00557F; }\nh4 { color: white; background: #00557F; }\n \na { color: #AA5500; }\n' +</style> +</head> +<body><a NAME="top" ID="top"></a> +<h1>eric5.Graphics.AssociationItem</h1> +<p> +Module implementing a graphics item for an association between two items. +</p> +<h3>Global Attributes</h3> +<table> +<tr><td>Center</td></tr><tr><td>East</td></tr><tr><td>Generalisation</td></tr><tr><td>Imports</td></tr><tr><td>NoRegion</td></tr><tr><td>Normal</td></tr><tr><td>North</td></tr><tr><td>NorthEast</td></tr><tr><td>NorthWest</td></tr><tr><td>South</td></tr><tr><td>SouthEast</td></tr><tr><td>SouthWest</td></tr><tr><td>West</td></tr> +</table> +<h3>Classes</h3> +<table> +<tr> +<td><a href="#AssociationItem">AssociationItem</a></td> +<td>Class implementing a graphics item for an association between two items.</td> +</tr> +</table> +<h3>Functions</h3> +<table> +<tr><td>None</td></tr> +</table> +<hr /><hr /> +<a NAME="AssociationItem" ID="AssociationItem"></a> +<h2>AssociationItem</h2> +<p> + Class implementing a graphics item for an association between two items. +</p><p> + The association is drawn as an arrow starting at the first items and + ending at the second. +</p> +<h3>Derived from</h3> +E4ArrowItem +<h3>Class Attributes</h3> +<table> +<tr><td>None</td></tr> +</table> +<h3>Methods</h3> +<table> +<tr> +<td><a href="#AssociationItem.__init__">AssociationItem</a></td> +<td>Constructor</td> +</tr><tr> +<td><a href="#AssociationItem.__calculateEndingPoints_center">__calculateEndingPoints_center</a></td> +<td>Private method to calculate the ending points of the association item.</td> +</tr><tr> +<td><a href="#AssociationItem.__calculateEndingPoints_rectangle">__calculateEndingPoints_rectangle</a></td> +<td>Private method to calculate the ending points of the association item.</td> +</tr><tr> +<td><a href="#AssociationItem.__findIntersection">__findIntersection</a></td> +<td>Method to calculate the intersection point of two lines.</td> +</tr><tr> +<td><a href="#AssociationItem.__findPointRegion">__findPointRegion</a></td> +<td>Private method to find out, which region of rectangle rect contains the point (PosX, PosY) and returns the region number.</td> +</tr><tr> +<td><a href="#AssociationItem.__findRectIntersectionPoint">__findRectIntersectionPoint</a></td> +<td>Private method to find the intersetion point of a line with a rectangle.</td> +</tr><tr> +<td><a href="#AssociationItem.__mapRectFromItem">__mapRectFromItem</a></td> +<td>Private method to map item's rectangle to this item's coordinate system.</td> +</tr><tr> +<td><a href="#AssociationItem.__updateEndPoint">__updateEndPoint</a></td> +<td>Private method to update an endpoint.</td> +</tr><tr> +<td><a href="#AssociationItem.unassociate">unassociate</a></td> +<td>Public method to unassociate from the widgets.</td> +</tr><tr> +<td><a href="#AssociationItem.widgetMoved">widgetMoved</a></td> +<td>Public method to recalculate the association after a widget was moved.</td> +</tr> +</table> +<a NAME="AssociationItem.__init__" ID="AssociationItem.__init__"></a> +<h4>AssociationItem (Constructor)</h4> +<b>AssociationItem</b>(<i>itemA, itemB, type = Normal, parent = None</i>) +<p> + Constructor +</p><dl> +<dt><i>itemA</i></dt> +<dd> +first widget of the association +</dd><dt><i>itemB</i></dt> +<dd> +second widget of the association +</dd><dt><i>type</i></dt> +<dd> +type of the association. This must be one of + <ul> + <li>Normal (default)</li> + <li>Generalisation</li> + <li>Imports</li> + </ul> +</dd><dt><i>parent=</i></dt> +<dd> +reference to the parent object (QGraphicsItem) +</dd> +</dl><a NAME="AssociationItem.__calculateEndingPoints_center" ID="AssociationItem.__calculateEndingPoints_center"></a> +<h4>AssociationItem.__calculateEndingPoints_center</h4> +<b>__calculateEndingPoints_center</b>(<i></i>) +<p> + Private method to calculate the ending points of the association item. +</p><p> + The ending points are calculated from the centers of the + two associated items. +</p><a NAME="AssociationItem.__calculateEndingPoints_rectangle" ID="AssociationItem.__calculateEndingPoints_rectangle"></a> +<h4>AssociationItem.__calculateEndingPoints_rectangle</h4> +<b>__calculateEndingPoints_rectangle</b>(<i></i>) +<p> + Private method to calculate the ending points of the association item. +</p><p> + The ending points are calculated by the following method. +</p><p> + For each item the diagram is divided in four Regions by its diagonals + as indicated below + <pre> + \ Region 2 / + \ / + |--------| + | \ / | + | \ / | + | \/ | + Region 1 | /\ | Region 3 + | / \ | + | / \ | + |--------| + / \ + / Region 4 \ + </pre> +</p><p> + Each diagonal is defined by two corners of the bounding rectangle +</p><p> + To calculate the start point we have to find out in which + region (defined by itemA's diagonals) is itemB's TopLeft corner + (lets call it region M). After that the start point will be + the middle point of rectangle's side contained in region M. +</p><p> + To calculate the end point we repeat the above but in the opposite direction + (from itemB to itemA) +</p><a NAME="AssociationItem.__findIntersection" ID="AssociationItem.__findIntersection"></a> +<h4>AssociationItem.__findIntersection</h4> +<b>__findIntersection</b>(<i>p1, p2, p3, p4</i>) +<p> + Method to calculate the intersection point of two lines. +</p><p> + The first line is determined by the points p1 and p2, the second + line by p3 and p4. If the intersection point is not contained in + the segment p1p2, then it returns (-1.0, -1.0). +</p><p> + For the function's internal calculations remember:<br /> + QT coordinates start with the point (0,0) as the topleft corner + and x-values increase from left to right and y-values increase + from top to bottom; it means the visible area is quadrant I in + the regular XY coordinate system +</p><p> + <pre> + Quadrant II | Quadrant I + -----------------|----------------- + Quadrant III | Quadrant IV + </pre> +</p><p> + In order for the linear function calculations to work in this method + we must switch x and y values (x values become y values and viceversa) +</p><dl> +<dt><i>p1</i></dt> +<dd> +first point of first line (QPointF) +</dd><dt><i>p2</i></dt> +<dd> +second point of first line (QPointF) +</dd><dt><i>p3</i></dt> +<dd> +first point of second line (QPointF) +</dd><dt><i>p4</i></dt> +<dd> +second point of second line (QPointF) +</dd> +</dl><dl> +<dt>Returns:</dt> +<dd> +the intersection point (QPointF) +</dd> +</dl><a NAME="AssociationItem.__findPointRegion" ID="AssociationItem.__findPointRegion"></a> +<h4>AssociationItem.__findPointRegion</h4> +<b>__findPointRegion</b>(<i>rect, posX, posY</i>) +<p> + Private method to find out, which region of rectangle rect contains the point + (PosX, PosY) and returns the region number. +</p><dl> +<dt><i>rect</i></dt> +<dd> +rectangle to calculate the region for (QRectF) +</dd><dt><i>posX</i></dt> +<dd> +x position of point (float) +</dd><dt><i>posY</i></dt> +<dd> +y position of point (float) +</dd> +</dl><dl> +<dt>Returns:</dt> +<dd> +the calculated region number<br /> + West = Region 1<br /> + North = Region 2<br /> + East = Region 3<br /> + South = Region 4<br /> + NorthWest = On diagonal 2 between Region 1 and 2<br /> + NorthEast = On diagonal 1 between Region 2 and 3<br /> + SouthEast = On diagonal 2 between Region 3 and 4<br /> + SouthWest = On diagonal 1 between Region4 and 1<br /> + Center = On diagonal 1 and On diagonal 2 (the center)<br /> +</dd> +</dl><a NAME="AssociationItem.__findRectIntersectionPoint" ID="AssociationItem.__findRectIntersectionPoint"></a> +<h4>AssociationItem.__findRectIntersectionPoint</h4> +<b>__findRectIntersectionPoint</b>(<i>item, p1, p2</i>) +<p> + Private method to find the intersetion point of a line with a rectangle. +</p><dl> +<dt><i>item</i></dt> +<dd> +item to check against +</dd><dt><i>p1</i></dt> +<dd> +first point of the line (QPointF) +</dd><dt><i>p2</i></dt> +<dd> +second point of the line (QPointF) +</dd> +</dl><dl> +<dt>Returns:</dt> +<dd> +the intersection point (QPointF) +</dd> +</dl><a NAME="AssociationItem.__mapRectFromItem" ID="AssociationItem.__mapRectFromItem"></a> +<h4>AssociationItem.__mapRectFromItem</h4> +<b>__mapRectFromItem</b>(<i>item</i>) +<p> + Private method to map item's rectangle to this item's coordinate system. +</p><dl> +<dt><i>item</i></dt> +<dd> +reference to the item to be mapped (QGraphicsRectItem) +</dd> +</dl><dl> +<dt>Returns:</dt> +<dd> +item's rectangle in local coordinates (QRectF) +</dd> +</dl><a NAME="AssociationItem.__updateEndPoint" ID="AssociationItem.__updateEndPoint"></a> +<h4>AssociationItem.__updateEndPoint</h4> +<b>__updateEndPoint</b>(<i>region, isWidgetA</i>) +<p> + Private method to update an endpoint. +</p><dl> +<dt><i>region</i></dt> +<dd> +the region for the endpoint (integer) +</dd><dt><i>isWidgetA</i></dt> +<dd> +flag indicating update for itemA is done (boolean) +</dd> +</dl><a NAME="AssociationItem.unassociate" ID="AssociationItem.unassociate"></a> +<h4>AssociationItem.unassociate</h4> +<b>unassociate</b>(<i></i>) +<p> + Public method to unassociate from the widgets. +</p><a NAME="AssociationItem.widgetMoved" ID="AssociationItem.widgetMoved"></a> +<h4>AssociationItem.widgetMoved</h4> +<b>widgetMoved</b>(<i></i>) +<p> + Public method to recalculate the association after a widget was moved. +</p> +<div align="right"><a href="#top">Up</a></div> +<hr /> +</body></html> \ No newline at end of file