<!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/picture/picture.doc:4 --> <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1"> <title>Picture</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>Picture</h1> <p> This example shows how to make a picture, store it to a file, and read it as a set of drawing commands. <p> <hr> <p> Implementation: <p> <pre>/**************************************************************************** ** $Id: qt/picture.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 Qt. This example ** program may be used, distributed and modified without limitation. ** *****************************************************************************/ #include <<a href="qapplication-h.html">qapplication.h</a>> #include <<a href="qpainter-h.html">qpainter.h</a>> #include <<a href="qpicture-h.html">qpicture.h</a>> #include <<a href="qpixmap-h.html">qpixmap.h</a>> #include <<a href="qwidget-h.html">qwidget.h</a>> #include <<a href="qmessagebox-h.html">qmessagebox.h</a>> #include <<a href="qfile-h.html">qfile.h</a>> #include <ctype.h> void paintCar( <a href="qpainter.html">QPainter</a> *p ) // paint a car { <a href="qpointarray.html">QPointArray</a> a; <a href="qbrush.html">QBrush</a> brush( Qt::yellow, Qt::SolidPattern ); <a name="x120"></a> p-><a href="qpainter.html#setBrush">setBrush</a>( brush ); // use solid, yellow brush <a name="x125"></a> a.setPoints( 5, 50,50, 350,50, 450,120, 450,250, 50,250 ); <a name="x115"></a> p-><a href="qpainter.html#drawPolygon">drawPolygon</a>( a ); // draw car body <a href="qfont.html">QFont</a> f( "courier", 12, QFont::Bold ); <a name="x121"></a> p-><a href="qpainter.html#setFont">setFont</a>( f ); <a href="qcolor.html">QColor</a> windowColor( 120, 120, 255 ); // a light blue color <a name="x108"></a> brush.<a href="qbrush.html#setColor">setColor</a>( windowColor ); // set this brush color p-><a href="qpainter.html#setBrush">setBrush</a>( brush ); // set brush <a name="x116"></a> p-><a href="qpainter.html#drawRect">drawRect</a>( 80, 80, 250, 70 ); // car window <a name="x117"></a> p-><a href="qpainter.html#drawText">drawText</a>( 180, 80, 150, 70, Qt::AlignCenter, "-- Qt --\nTrolltech AS" ); <a href="qpixmap.html">QPixmap</a> pixmap; <a name="x124"></a> if ( pixmap.<a href="qpixmap.html#load">load</a>("flag.bmp") ) // load and draw image <a name="x114"></a> p-><a href="qpainter.html#drawPixmap">drawPixmap</a>( 100, 85, pixmap ); <a name="x119"></a> p-><a href="qpainter.html#setBackgroundMode">setBackgroundMode</a>( Qt::OpaqueMode ); // set opaque mode p-><a href="qpainter.html#setBrush">setBrush</a>( Qt::DiagCrossPattern ); // black diagonal cross pattern <a name="x112"></a> p-><a href="qpainter.html#drawEllipse">drawEllipse</a>( 90, 210, 80, 80 ); // back wheel p-><a href="qpainter.html#setBrush">setBrush</a>( Qt::CrossPattern ); // black cross fill pattern p-><a href="qpainter.html#drawEllipse">drawEllipse</a>( 310, 210, 80, 80 ); // front wheel } class PictureDisplay : public <a href="qwidget.html">QWidget</a> // picture display widget { public: PictureDisplay( const char *fileName ); ~PictureDisplay(); protected: void paintEvent( <a href="qpaintevent.html">QPaintEvent</a> * ); void keyPressEvent( <a href="qkeyevent.html">QKeyEvent</a> * ); private: <a href="qpicture.html">QPicture</a> *pict; <a href="qstring.html">QString</a> name; }; <a name="f207"></a>PictureDisplay::PictureDisplay( const char *fileName ) { pict = new <a href="qpicture.html">QPicture</a>; name = fileName; <a name="x122"></a> if ( !pict-><a href="qpicture.html#load">load</a>(fileName) ) { // cannot load picture delete pict; pict = 0; name.<a href="qstring.html#sprintf">sprintf</a>( "Not able to load picture: %s", fileName ); } } PictureDisplay::~PictureDisplay() { delete pict; } void PictureDisplay::<a href="qwidget.html#paintEvent">paintEvent</a>( <a href="qpaintevent.html">QPaintEvent</a> * ) { <a href="qpainter.html">QPainter</a> paint( this ); // paint widget if ( pict ) <a name="x113"></a> paint.<a href="qpainter.html#drawPicture">drawPicture</a>( *pict ); // draw picture else paint.<a href="qpainter.html#drawText">drawText</a>( <a href="qwidget.html#rect">rect</a>(), AlignCenter, name ); } <a name="x127"></a>void PictureDisplay::<a href="qwidget.html#keyPressEvent">keyPressEvent</a>( <a href="qkeyevent.html">QKeyEvent</a> *k ) { <a name="x109"></a> switch ( tolower(k-><a href="qkeyevent.html#ascii">ascii</a>()) ) { case 'r': // reload pict-><a href="qpicture.html#load">load</a>( name ); <a href="qwidget.html#update">update</a>(); break; case 'q': // quit <a name="x106"></a> QApplication::<a href="qapplication.html#exit">exit</a>(); break; } } int main( int argc, char **argv ) { <a href="qapplication.html">QApplication</a> a( argc, argv ); // QApplication required! const char *fileName = "car.pic"; // default picture file name if ( argc == 2 ) // use argument as file name fileName = argv[1]; if ( !QFile::exists(fileName) ) { <a href="qpicture.html">QPicture</a> pict; // our picture <a href="qpainter.html">QPainter</a> paint; // our painter <a name="x111"></a> paint.<a href="qpainter.html#begin">begin</a>( &pict ); // begin painting onto picture paintCar( &paint ); // paint! <a name="x118"></a> paint.<a href="qpainter.html#end">end</a>(); // painting done <a name="x123"></a> pict.<a href="qpicture.html#save">save</a>( fileName ); // save picture <a name="x110"></a> QMessageBox::<a href="qmessagebox.html#information">information</a>(0, "Qt Example - Picture", "Saved. Run me again!"); return 0; } else { PictureDisplay test( fileName ); // create picture display a.<a href="qapplication.html#setMainWidget">setMainWidget</a>( &test); // set main widget test.<a href="qwidget.html#setCaption">setCaption</a>("Qt Example - Picture"); test.<a href="qwidget.html#show">show</a>(); // show it return a.<a href="qapplication.html#exec">exec</a>(); // start event loop } } </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 © 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>