summaryrefslogtreecommitdiffstats
path: root/doc/html/drawlines-example.html
blob: eb804914e01c5cac572d8b736d8bbae0db096991 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
<!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/examples/drawlines/drawlines.doc:5 -->
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>Connect the Points</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&nbsp;Classes</font></a>
 | <a href="mainclasses.html">
<font color="#004faf">Main&nbsp;Classes</font></a>
 | <a href="annotated.html">
<font color="#004faf">Annotated</font></a>
 | <a href="groups.html">
<font color="#004faf">Grouped&nbsp;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>Connect the Points</h1>

   
<p> 
This example shows very simple mouse-based user interaction and
painting without any world transform matrix or other advanced
features.  Run the program, click the button, move the mouse,
release the button, and watch the lines get drawn.
<p> <hr>
<p> Implementation:
<p> <pre>/****************************************************************************
** $Id: qt/connect.cpp   3.3.8   edited Jan 11 14:37 $
**
** Copyright (C) 1992-2007 Trolltech ASA.  All rights reserved.
**
** This file is part of an example program for TQt.  This example
** program may be used, distributed and modified without limitation.
**
*****************************************************************************/

#include &lt;<a href="qwidget-h.html">qwidget.h</a>&gt;
#include &lt;<a href="qpainter-h.html">qpainter.h</a>&gt;
#include &lt;<a href="qapplication-h.html">qapplication.h</a>&gt;
#include &lt;stdlib.h&gt;


const int MAXPOINTS = 2000;                     // maximum number of points
const int MAXCOLORS = 40;


//
// ConnectWidget - draws connected lines
//

class ConnectWidget : public <a href="qwidget.html">TQWidget</a>
{
public:
    ConnectWidget( <a href="qwidget.html">TQWidget</a> *parent=0, const char *name=0 );
   ~ConnectWidget();
protected:
    void        paintEvent( <a href="qpaintevent.html">TQPaintEvent</a> * );
    void        mousePressEvent( <a href="qmouseevent.html">TQMouseEvent</a> *);
    void        mouseReleaseEvent( <a href="qmouseevent.html">TQMouseEvent</a> *);
    void        mouseMoveEvent( <a href="qmouseevent.html">TQMouseEvent</a> *);
private:
    <a href="qpoint.html">TQPoint</a>     *points;                         // point array
    <a href="qcolor.html">TQColor</a>     *colors;                         // color array
    int         count;                          // count = number of points
    bool        down;                           // TRUE if mouse down
};


//
// Constructs a ConnectWidget.
//

<a name="f475"></a>ConnectWidget::ConnectWidget( <a href="qwidget.html">TQWidget</a> *parent, const char *name )
    : <a href="qwidget.html">TQWidget</a>( parent, name, WStaticContents )
{
    <a href="qwidget.html#setBackgroundColor">setBackgroundColor</a>( white );                // white background
    count = 0;
    down = FALSE;
    points = new <a href="qpoint.html">TQPoint</a>[MAXPOINTS];
    colors = new <a href="qcolor.html">TQColor</a>[MAXCOLORS];
    for ( int i=0; i&lt;MAXCOLORS; i++ )           // init color array
        colors[i] = TQColor( rand()&amp;255, rand()&amp;255, rand()&amp;255 );
}

ConnectWidget::~ConnectWidget()
{
    delete[] points;                            // cleanup
    delete[] colors;
}


//
// Handles paint events for the connect widget.
//

<a name="x1661"></a>void ConnectWidget::<a href="qwidget.html#paintEvent">paintEvent</a>( <a href="qpaintevent.html">TQPaintEvent</a> * )
{
    <a href="qpainter.html">TQPainter</a> paint( this );
    for ( int i=0; i&lt;count-1; i++ ) {           // connect all points
        for ( int j=i+1; j&lt;count; j++ ) {
            paint.<a href="qpainter.html#setPen">setPen</a>( colors[rand()%MAXCOLORS] ); // set random pen color
<a name="x1655"></a>            paint.<a href="qpainter.html#drawLine">drawLine</a>( points[i], points[j] ); // draw line
        }
    }
}


//
// Handles mouse press events for the connect widget.
//

<a name="x1659"></a>void ConnectWidget::<a href="qwidget.html#mousePressEvent">mousePressEvent</a>( <a href="qmouseevent.html">TQMouseEvent</a> * )
{
    down = TRUE;
    count = 0;                                  // start recording points
    <a href="qwidget.html#erase">erase</a>();                                    // erase widget contents
}


//
// Handles mouse release events for the connect widget.
//

<a name="x1660"></a>void ConnectWidget::<a href="qwidget.html#mouseReleaseEvent">mouseReleaseEvent</a>( <a href="qmouseevent.html">TQMouseEvent</a> * )
{
    down = FALSE;                               // done recording points
    <a href="qwidget.html#update">update</a>();                                   // draw the lines
}


//
// Handles mouse move events for the connect widget.
//

<a name="x1658"></a>void ConnectWidget::<a href="qwidget.html#mouseMoveEvent">mouseMoveEvent</a>( <a href="qmouseevent.html">TQMouseEvent</a> *e )
{
    if ( down &amp;&amp; count &lt; MAXPOINTS ) {
        <a href="qpainter.html">TQPainter</a> paint( this );
<a name="x1654"></a>        points[count++] = e-&gt;<a href="qmouseevent.html#pos">pos</a>();             // add point
<a name="x1656"></a>        paint.<a href="qpainter.html#drawPoint">drawPoint</a>( e-&gt;<a href="qmouseevent.html#pos">pos</a>() );            // plot point
    }
}


//
// Create and display a ConnectWidget.
//

int main( int argc, char **argv )
{
    <a href="qapplication.html">TQApplication</a> a( argc, argv );
    ConnectWidget connect;
#ifndef QT_NO_WIDGET_TOPEXTRA   // for TQt/Embedded minimal build
    connect.<a href="qwidget.html#setCaption">setCaption</a>( "TQt Example - Draw lines");
#endif
    a.<a href="qapplication.html#setMainWidget">setMainWidget</a>( &amp;connect );
    connect.<a href="qwidget.html#show">show</a>();
    return a.<a href="qapplication.html#exec">exec</a>();
}
</pre>

<p>See also <a href="examples.html">Examples</a>.

<!-- eof -->
<p><address><hr><div align=center>
<table width=100% cellspacing=0 border=0><tr>
<td>Copyright &copy; 2007
<a href="troll.html">Trolltech</a><td align=center><a href="trademarks.html">Trademarks</a>
<td align=right><div align=right>TQt 3.3.8</div>
</table></div></address></body>
</html>