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| author | Timothy Pearson <kb9vqf@pearsoncomputing.net> | 2011-11-08 12:31:36 -0600 |
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| committer | Timothy Pearson <kb9vqf@pearsoncomputing.net> | 2011-11-08 12:31:36 -0600 |
| commit | d796c9dd933ab96ec83b9a634feedd5d32e1ba3f (patch) | |
| tree | 6e3dcca4f77e20ec8966c666aac7c35bd4704053 /doc/html/tutorial1-01.html | |
| download | tqt3-d796c9dd933ab96ec83b9a634feedd5d32e1ba3f.tar.gz tqt3-d796c9dd933ab96ec83b9a634feedd5d32e1ba3f.zip | |
Test conversion to TQt3 from Qt3 8c6fc1f8e35fd264dd01c582ca5e7549b32ab731
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diff --git a/doc/html/tutorial1-01.html b/doc/html/tutorial1-01.html new file mode 100644 index 000000000..97005180a --- /dev/null +++ b/doc/html/tutorial1-01.html @@ -0,0 +1,168 @@ +<!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/doc/tutorial.doc:80 --> +<html> +<head> +<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1"> +<title>TQt Tutorial - Chapter 1: Hello, World!</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>TQt Tutorial - Chapter 1: Hello, World!</h1> + + +<p> <center><img src="t1.png" alt="Screenshot of tutorial one"></center> +<p> This first program is a simple hello-world example. It contains only +the bare minimum you need to get a TQt application up and running. +The picture above is a snapshot of this program. +<p> <pre>/**************************************************************** +** +** TQt tutorial 1 +** +****************************************************************/ + +#include <<a href="qapplication-h.html">qapplication.h</a>> +#include <<a href="qpushbutton-h.html">qpushbutton.h</a>> + + +int main( int argc, char **argv ) +{ + <a href="qapplication.html">TQApplication</a> a( argc, argv ); + + <a href="qpushbutton.html">TQPushButton</a> hello( "Hello world!", 0 ); + hello.<a href="qwidget.html#resize">resize</a>( 100, 30 ); + + a.<a href="qapplication.html#setMainWidget">setMainWidget</a>( &hello ); + hello.<a href="qwidget.html#show">show</a>(); + return a.<a href="qapplication.html#exec">exec</a>(); +} +</pre> + + + +<p> <h2> Line-by-line Walkthrough +</h2> +<a name="1"></a><p> <pre> #include <<a href="qapplication-h.html">qapplication.h</a>> +</pre> +<p> This line includes the <a href="qapplication.html">TQApplication</a> class definition. There has to be +exactly one TQApplication object in every application that uses TQt. +TQApplication manages various application-wide resources, such as the +default font and cursor. +<p> <pre> #include <<a href="qpushbutton-h.html">qpushbutton.h</a>> +</pre> +<p> This line includes the <a href="qpushbutton.html">TQPushButton</a> class definition. The +<a href="hierarchy.html">reference documentation</a> for each class +mentions at the top which file needs to be included to use that class. +<p> TQPushButton is a classical GUI push button that the user can press +and release. It manages its own look and feel, like every other <a href="qwidget.html">TQWidget</a>. A widget is a user interface object that can process user +input and draw graphics. The programmer can change both the overall +<a href="qapplication.html#setStyle">look and feel</a> and many minor +properties of it (such as color), as well as the widget's content. A +TQPushButton can show either a text or a <a href="qpixmap.html">TQPixmap</a>. +<p> <pre> int main( int argc, char **argv ) + { +</pre> +<p> The main() function is the entry point to the program. Almost always +when using TQt, main() only needs to perform some kind of initialization +before passing the control to the TQt library, which then tells the +program about the user's actions via events. +<p> <tt>argc</tt> is the number of command-line arguments and <tt>argv</tt> is the +array of command-line arguments. This is a C/C++ feature. It is not +specific to TQt; however, TQt needs to process these arguments (see +following). +<p> <pre> <a href="qapplication.html">TQApplication</a> a( argc, argv ); +</pre> +<p> <tt>a</tt> is this program's <a href="qapplication.html">TQApplication</a>. Here it is created and processes +some of the command-line arguments (such as -display under X Window). +Note that all command-line arguments recognized by TQt are removed from +<tt>argv</tt> (and <tt>argc</tt> is decremented accordingly). See the <a href="qapplication.html#argv">TQApplication::argv</a>() documentation for details. +<p> <strong>Note:</strong> It is essential that the TQApplication object be +created before any window-system parts of TQt are used. +<p> <pre> <a href="qpushbutton.html">TQPushButton</a> hello( "Hello world!", 0 ); +</pre> +<p> Here, <em>after</em> the TQApplication, comes the first window-system code: A +push button is created. +<p> The button is set up to display the text "Hello world!" and be a +window of its own (because the constructor specifies 0 for the parent +window, inside which the button should be located). +<p> <pre> <a name="x2285"></a> hello.<a href="qwidget.html#resize">resize</a>( 100, 30 ); +</pre> +<p> The button is set up to be 100 pixels wide and 30 pixels high (plus the +window system frame). In this case we don't care about the button's +position, and we accept the default value. +<p> <pre> <a name="x2284"></a> a.<a href="qapplication.html#setMainWidget">setMainWidget</a>( &hello ); +</pre> +<p> The push button is chosen as the main widget for the application. If +the user closes a main widget, the application exits. +<p> You don't have to have a main widget, but most programs do have one. +<p> <pre> <a name="x2286"></a> hello.<a href="qwidget.html#show">show</a>(); +</pre> +<p> A widget is never visible when you create it. You must call show() to +make it visible. +<p> <pre> <a name="x2283"></a> return a.<a href="qapplication.html#exec">exec</a>(); +</pre> +<p> This is where main() passes control to TQt, and exec() will return when +the application exits. +<p> In exec(), TQt receives and processes user and system events and passes +these on to the appropriate widgets. +<p> <pre> } +</pre> +<p> You should now try to compile and run this program. +<p> <a name="compiling"></a> +<h2> Compiling +</h2> +<a name="2"></a><p> To compile a C++ application you need to create a makefile. The +easiest way to create a makefile for TQt is to use the <a href="qmake-manual.html">qmake</a> build tool supplied with TQt. If you've +saved <tt>main.cpp</tt> in its own directory, all you have to do is: +<pre> +qmake -project +qmake +</pre> + +<p> The first command tells <a href="qmake-manual.html">qmake</a> to +create a <tt>.pro</tt> (project) file. The second command tells it to create +a (platform-specific) makefile based on the project file. You should +now be able to type <tt>make</tt> (or <tt>nmake</tt> if you're using Visual +Studio) and then run your first TQt application! +<p> <h2> Behavior +</h2> +<a name="3"></a><p> When you run it, you will see a small window filled with a single +button, and on it you can read the famous words, Hello World! +<p> <h2> Exercises +</h2> +<a name="4"></a><p> Try to resize the window. Press the button. If you're running X +Window, try running the program with the -geometry option +(for example, <tt>-geometry 100x200+10+20</tt>). +<p> You're now ready for <a href="tutorial1-02.html">Chapter 2.</a> +<p> [<a href="tutorial1-02.html">Next tutorial</a>] +[<a href="tutorial.html">Main tutorial page</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>TQt 3.3.8</div> +</table></div></address></body> +</html> |