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diff --git a/doc/html/motif-walkthrough-1.html b/doc/html/motif-walkthrough-1.html new file mode 100644 index 0000000..f320757 --- /dev/null +++ b/doc/html/motif-walkthrough-1.html @@ -0,0 +1,98 @@ +<!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/extensions/motif/doc/walkthrough.doc:147 --> +<html> +<head> +<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1"> +<title>Getting Started</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>Getting Started</h1> + + + +[ <a href="motif-walkthrough.html">Home</a> ] +[ <a href="motif-walkthrough-2.html">Next: Preparing to Migrate the User Interface</a> ] +<p> <h2> Starting with <a href="qmotif.html">QMotif</a> and <a href="qapplication.html">QApplication</a> +</h2> +<a name="1"></a><p> To be able to use Qt, we need to create a QApplication object. The +QApplication class controls all the event delivery and display +management for all other Qt objects and widgets. We need to use the +QMotif class from the <em>Qt <a href="motif-extension.html#Motif">Motif</a> Extension</em> to allow QApplication +and the <tt>XtAppContext</tt> to coexist. +<p> The QApplication object must be created in the <tt>main()</tt> function. +We will need to modify <tt>todo.c</tt> to compile with a C++ compiler, so we +rename <tt>todo.c</tt> to <tt>todo.cpp</tt>. +<p> Next, we add the appropriate includes for the QMotif and QApplication +classes. +<p> + +<pre></pre> +<p> Next, we create the QMotif and QApplication objects. We create QMotif +with a foreign <tt>XtAppContext</tt>, and we create QApplication with a +foreign <tt>Display</tt>. +<p> <pre></pre> +<p> The next change is not yet necessary, but it is included to show that +the <em>Qt Motif Extension</em> provides a complete integration. +Normally, a Motif based program would use the <tt>XtAppMainLoop()</tt> +function to run the application's event loop. This is still possible, +but since we are migrating to the Qt toolkit, we prefer to use the +<a href="qapplication.html#exec">QApplication::exec</a>() function for running the event loop. +<p> <pre></pre> +<p> Since we renamed <tt>todo.c</tt> to <tt>todo.cpp</tt>, we must change the +project file and rerun <em>qmake</em> to regenerate our <tt>Makefile</tt>. When we +build our project, there are compile and link errors: we will fix +these in the following section. +<p> <h2> Migrating to C++ +</h2> +<a name="2"></a><p> We need to convert the code in this file to proper C++ code. +Fortunately, the changes are not too large. Most files included from +existing C projects are not C++ compatible, so we make them compatible +by wrapping them in an <tt>extern "C"</tt> block. +<p> + +<p> <pre></pre> +<p> Global C functions that are forward declared must also be wrapped into +an <tt>extern "C"</tt> block. +<p> <pre></pre> +<p> The <tt>manageCB()</tt> function needs to be converted to proper C++. +<p> <pre></pre> +<p> And we need to fix two invalid casts. One is in the <tt>Save()</tt> function. +<p> <pre></pre> +<p> The other invalid cast is in the <tt>Open()</tt> function. +<p> <pre></pre> +<p> After these changes, the project compiles and links, and the +application runs and operates correctly. +<p> [ <a href="motif-walkthrough.html">Home</a> ] +[ <a href="motif-walkthrough-2.html">Next: Preparing to Migrate the User Interface</a> ] +<p> +<!-- 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> |