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| author | Timothy Pearson <kb9vqf@pearsoncomputing.net> | 2011-07-10 15:24:15 -0500 |
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| committer | Timothy Pearson <kb9vqf@pearsoncomputing.net> | 2011-07-10 15:24:15 -0500 |
| commit | bd0f3345a938b35ce6a12f6150373b0955b8dd12 (patch) | |
| tree | 7a520322212d48ebcb9fbe1087e7fca28b76185c /doc/html/tutorial1-03.html | |
| download | qt3-bd0f3345a938b35ce6a12f6150373b0955b8dd12.tar.gz qt3-bd0f3345a938b35ce6a12f6150373b0955b8dd12.zip | |
Add Qt3 development HEAD version
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| -rw-r--r-- | doc/html/tutorial1-03.html | 122 |
1 files changed, 122 insertions, 0 deletions
diff --git a/doc/html/tutorial1-03.html b/doc/html/tutorial1-03.html new file mode 100644 index 0000000..cac92da --- /dev/null +++ b/doc/html/tutorial1-03.html @@ -0,0 +1,122 @@ +<!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:303 --> +<html> +<head> +<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1"> +<title>Qt Tutorial - Chapter 3: Family Values</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>Qt Tutorial - Chapter 3: Family Values</h1> + + +<p> <center><img src="t3.png" alt="Screenshot of tutorial three"></center> +<p> This example shows how to create parent and child widgets. +<p> We'll keep it simple and use just a single parent and a lone child. +<p> <pre>/**************************************************************** +** +** Qt tutorial 3 +** +****************************************************************/ + +#include <<a href="qapplication-h.html">qapplication.h</a>> +#include <<a href="qpushbutton-h.html">qpushbutton.h</a>> +#include <<a href="qfont-h.html">qfont.h</a>> +#include <<a href="qvbox-h.html">qvbox.h</a>> + +int main( int argc, char **argv ) +{ + <a href="qapplication.html">QApplication</a> a( argc, argv ); + + <a href="qvbox.html">QVBox</a> box; + box.<a href="qwidget.html#resize">resize</a>( 200, 120 ); + + <a href="qpushbutton.html">QPushButton</a> quit( "Quit", &box ); + quit.<a href="qwidget.html#setFont">setFont</a>( QFont( "Times", 18, QFont::Bold ) ); + + QObject::<a href="qobject.html#connect">connect</a>( &quit, SIGNAL(<a href="qbutton.html#clicked">clicked</a>()), &a, SLOT(<a href="qapplication.html#quit">quit</a>()) ); + + a.<a href="qapplication.html#setMainWidget">setMainWidget</a>( &box ); + box.<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="qvbox-h.html">qvbox.h</a>> +</pre> +<p> We add an include of qvbox.h to get the layout class we'll use. +<p> <pre> <a href="qvbox.html">QVBox</a> box; +</pre> +<p> Here we simply create a vertical box container. The <a href="qvbox.html">QVBox</a> arranges +its child widgets in a vertical row, one above the other, handing out +space according to each child's <a href="qwidget.html#sizePolicy">QWidget::sizePolicy</a>(). +<p> <pre> <a name="x2300"></a> box.<a href="qwidget.html#resize">resize</a>( 200, 120 ); +</pre> +<p> We set its width to 200 pixels and the height to 120 pixels. +<p> <pre> <a href="qpushbutton.html">QPushButton</a> quit( "Quit", &box ); +</pre> +<p> A child is born. +<p> This <a href="qpushbutton.html">QPushButton</a> is created with both a text ("Quit") and a parent +(box). A child widget is always on top of its parent. When +displayed, it is clipped by its parent's bounds. +<p> The parent widget, the QVBox, automatically adds the child centered in +its box. Because nothing else is added, the button gets all the space +the parent has. +<p> <pre> <a name="x2302"></a> box.<a href="qwidget.html#show">show</a>(); +</pre> +<p> When a parent widget is shown, it will call show for all its children +(except those on which you have done an explicit <a href="qwidget.html#hide">QWidget::hide</a>()). +<p> <h2> Behavior +</h2> +<a name="2"></a><p> The button no longer fills the entire widget. Instead, it gets a +"natural" size. This is because there is now a new top-level widget, +which uses the button's size hint and size change policy to set the +button's size and position. (See <a href="qwidget.html#sizeHint">QWidget::sizeHint</a>() and <a href="qwidget.html#setSizePolicy">QWidget::setSizePolicy</a>() for more information about these functions.) +<p> (See <a href="tutorial1-01.html#compiling">Compiling</a> for how to create a +makefile and build the application.) +<p> <h2> Exercises +</h2> +<a name="3"></a><p> Try resizing the window. How does the button change? What is the +button's size-change policy? What happens to the button's height if +you run the program with a bigger font? What happens if you try to +make the window <em>really</em> small? +<p> You're now ready for <a href="tutorial1-04.html">Chapter 4.</a> +<p> [<a href="tutorial1-02.html">Previous tutorial</a>] +[<a href="tutorial1-04.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>Qt 3.3.8</div> +</table></div></address></body> +</html> |