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<td align="right" valign="center"><img src="logo32.png" align="right" width="64" height="32" border="0"></td></tr></table><h1 align=center>Walkthrough: A simple QFont demonstration</h1>
<p>
<p> The following walkthrough
will show you how to make use of the font setting and manipulation techniques
provided by <a href="qfont.html">QFont</a>.
<p> In addition it will show some aspects of widget layout -- if you prefer leaving
this job to Qt Designer simply skip the <a href="#layout()">relevant paragraphs.</a>
Moreover, if you
have asked yourself how to add strings to a <a href="qstringlist.html">QStringList</a> and how to
step through its members, you will know after reading this walkthrough,
or skipping to the relevant explanations in <a href="#showFontInfo()_QStringList">Viewer::showFontInfo()</a> and <a href="#setFontSubstitutions()">Viewer::setFontSubstitutions().</a>
<p> To get the most out of the walkthrough you should at least be familiar with
<a href="signalsandslots.html">signals and slots.</a>
<p> The <a href="simple-font-demo-example.html">example program</a>
consists of a widget containing two <a href="qtextview.html">QTextView</a>s side by side.
The one on the left shows greetings in English, Russian, and Hebrew.
The one on the right shows some information about the fonts used to
draw these greetings. Three push buttons in the bottom of the main window
change the font used to display the greetings.
<p> Note that the fonts and font characteristics in the example have been chosen
for demonstration purposes only -- in a real world application they
would rather count for bad design.
<p> <h3><a name="viewer.h">The API of the custom widget</a></h3>
<p> The widget used in this example is a custom widget named
<em>Viewer</em>.
<p>
<pre> #include <<a href="qwidget-h.html">qwidget.h</a>>
#include <<a href="qfont-h.html">qfont.h</a>>
</pre>
<p> As we derive it from <a href="qwidget.html">QWidget</a> we include the relevant header file.
Additionally we use a <a href="qfont.html">QFont</a> object as a function argument, and
therefore include the QFont class.
<p> <pre> class QTextView;
class QPushButton;
</pre>
<p> Furthermore we declare the use of the QTextView and the
<a href="qpushbutton.html">QPushButton</a> classes for class variables (we don't need to
include them at this stage yet because we only use pointers to these classes).
<p> <pre> class Viewer : public <a href="qwidget.html">QWidget</a>
{
<a href="metaobjects.html#Q_OBJECT">Q_OBJECT</a>
</pre>
<p> The <em>Viewer</em> widget will have slots, so don't forget to add the
<em>Q_OBJECT</em> macro.
<p> <pre> public:
Viewer();
</pre>
<p> As we won't use more than one instance of this class
there is no need for any complex constructors, a simple one without
any arguments should be sufficient.
<p> <pre> private slots:
void setDefault();
</pre>
<p> As previously mentioned we're going to have three push buttons. When the user
clicks on them, something should happen. Thus we define
<a href="#setDefault()">one slot that
sets the font in the greeting window back to the default,</a> ...
<p> <pre> void setSansSerif();
</pre>
<p> ... <a href="#setSansSerif()">one that switches to a sans serif font,</a>
and ...
<p> <pre> void setItalics();
</pre>
<p> ... <a href="#setItalics()">one that shows the greetings in italics.</a>
<p> <pre> private:
void setFontSubstitutions();
</pre>
<p> Will will write the greetings using different alphabets. For users who don't
have Unicode fonts installed we want to tell the application to try
to exchange missing characters in one font with appropriate characters
from other fonts. <a href="qfont.html">QFont</a> does such font substitutions on its own but
with <a href="#setFontSubstitutions()">this helper function</a>
we can define our preferred substitution pattern.
<p> <pre> void layout();
</pre>
<p> The task of putting the buttons and text views together we will put into
a separate <a href="#layout()">layout()</a> function.
This will make the code easier to understand and read.
<p> <pre> void showFontInfo( <a href="qfont.html">QFont</a> & );
</pre>
<p> <a href="#showFontInfo()">The last private function</a> reveals
font information in the text view on the right.
<p> <pre> <a href="qtextview.html">QTextView</a> * greetings;
<a href="qtextview.html">QTextView</a> * fontInfo;
<a href="qpushbutton.html">QPushButton</a> * defaultButton;
<a href="qpushbutton.html">QPushButton</a> * sansSerifButton;
<a href="qpushbutton.html">QPushButton</a> * italicsButton;
};
</pre>
<p> Last but not least we define the elements of our GUI as private
class variables.
<p> <h3><a name="viewer.cpp">The implementation of the Viewer widget</a></h3>
<p> Now we will implement the <em>Viewer</em> class.
<p>
<pre> #include "viewer.h"
#include <<a href="qstring-h.html">qstring.h</a>>
#include <<a href="qstringlist-h.html">qstringlist.h</a>>
#include <<a href="qtextview-h.html">qtextview.h</a>>
#include <<a href="qpushbutton-h.html">qpushbutton.h</a>>
#include <<a href="qlayout-h.html">qlayout.h</a>>
</pre>
<p> First we include the relevant header files -- obviously the
<a href="#viewer.h">header of the Viewer class</a> itself,
of the <a href="qpushbutton.html">QPushButton</a> and QTextView widgets, and of the <a href="qstring.html">QString</a>
and <a href="qstringlist.html">QStringList</a> classes. <em>qlayout.h</em> provides
classes for horizontal and vertical layout and will be used
in the <a href="#layout()">layout()</a> function.
<p> <a name="Viewer()"></a>
<p> <pre> Viewer::Viewer()
:<a href="qwidget.html">QWidget</a>()
{
</pre>
<p> As already mentioned the finger print of the <em>Viewer</em> constructor
is as simple as possible, without any arguments, derived from
the <a href="qwidget.html">QWidget</a> default constructor.
<p> <pre> setFontSubstitutions();
</pre>
<p> First we define the font substitutions -- for clarity reasons we
do this in a <a href="#setFontSubstitutions()">separate function.</a>
<p> <pre> <a name="x2400"></a> <a href="qstring.html">QString</a> greeting_heb = QString::<a href="qstring.html#fromUtf8">fromUtf8</a>( "\327\251\327\234\327\225\327\235" );
<a href="qstring.html">QString</a> greeting_ru = QString::<a href="qstring.html#fromUtf8">fromUtf8</a>( "\320\227\320\264\321\200\320\260\320\262\321\201\321\202\320\262\321\203\320\271\321\202\320\265" );
</pre>
<p> The Hebrew and the Russian greeting we have readily available as UTF8 encoded
strings.
To use them in a <a href="qstring.html">QString</a> we "import" them with <a href="qstring.html#fromUtf8">QString::fromUtf8</a>().
<p> <pre> <a href="qstring.html">QString</a> greeting_en( "Hello" );
</pre>
<p> Dor the English greeting we use a simple QString.
<p> <pre> greetings = new <a href="qtextview.html">QTextView</a>( this, "textview" );
</pre>
<p> Now we create the first widget as a child of <em>this</em> widget,
the QTextView with the identity name <em>textview</em> that shows the greetings.
<p> <pre> <a name="x2402"></a> greetings-><a href="qtextedit.html#setText">setText</a>( greeting_en + "\n" +
greeting_ru + "\n" +
greeting_heb );
</pre>
<p> Now we set the text shown by <em>greetings</em> to the three greetings.
<p> <pre> fontInfo = new <a href="qtextview.html">QTextView</a>( this, "fontinfo" );
</pre>
<p> The second text view we call <em>fontinfo</em> and create
it as a child of <em>this</em> <em>Viewer</em> widget.
<p> <pre> setDefault();
</pre>
<p> Using the <a href="#setDefault()">setDefault()</a> function we
apply the initial font to the greetings <em>greetings</em> and
fill the <em>fontInfo</em> textview with information about
the font used.
<p> <pre> defaultButton = new <a href="qpushbutton.html">QPushButton</a>( "Default", this,
"pushbutton1" );
</pre>
<p> Now we create the first of the three push buttons -- the one
that changes the font to the initial one -- with the label <em>Default</em>.
<p> <pre> <a name="x2410"></a> defaultButton-><a href="qwidget.html#setFont">setFont</a>( QFont( "times" ) );
</pre>
<p> The label should be printed in a member font of the Times family.
In the unlikely case that the user does not have installed a
matching font, <a href="qfont.html">QFont</a> is responsible in finding a replacement.
Note that case-sensitivity is no issue when specifying the font family.
<p> As we don't explicitly request a font size or weight, QFont tries to
find a default 12 pt font with normal boldness.
<p> <pre> <a name="x2387"></a> <a href="qobject.html#connect">connect</a>( defaultButton, SIGNAL( <a href="qbutton.html#clicked">clicked</a>() ),
this, SLOT( setDefault() ) );
</pre>
<p> In order to make something happening when the user clicks the
<em>defaultButton</em>, we connect the <a href="qbutton.html#clicked">QPushButton::clicked</a>() signals
issued from it to the <em>Viewer</em>'s <a href="#setDefault()">setDefault()</a>
slot.
<p> <pre> sansSerifButton = new <a href="qpushbutton.html">QPushButton</a>( "Sans Serif", this,
"pushbutton2" );
sansSerifButton-><a href="qwidget.html#setFont">setFont</a>( QFont( "Helvetica", 12 ) );
</pre>
<p> The newly created second button is labelled <em>Sans Serif</em>
in a 12 pt Helvetica font. Again if this is not possible because
the requested font is not available on the system, <a href="qfont.html">QFont</a> deals
with it and finds a replacement.
<p> <pre> <a href="qobject.html#connect">connect</a>( sansSerifButton, SIGNAL( <a href="qbutton.html#clicked">clicked</a>() ),
this, SLOT( setSansSerif() ) );
</pre>
<p> We connect the clicked() signal of the <em>sansSerifButton</em>
to the <a href="#setSansSerif()">setSansSerif()</a> slot.
<p> <pre> italicsButton = new <a href="qpushbutton.html">QPushButton</a>( "Italics", this,
"pushbutton3" );
italicsButton-><a href="qwidget.html#setFont">setFont</a>( QFont( "lucida", 12, QFont::Bold, TRUE ) );
</pre>
<p> <em>italicsButton</em>, the last push button, is labelled <em>Italics</em>.
This time we specify even more characteristics of the
label font. We wish it to be a 12 pt bold member of the Lucida family.
Also it should be in italics, indicated by the fourth QFont argument
being TRUE.
<p> <pre> <a href="qobject.html#connect">connect</a>( italicsButton, SIGNAL( <a href="qbutton.html#clicked">clicked</a>() ),
this, SLOT( setItalics() ) );
</pre>
<p> Again, the <em>italicsButton</em>'s clicked() signal is connected to
a slot of <em>this</em> <em>Viewer</em> object <a href="#setItalics()">setItalics().</a>
<p> <pre> <a href="qwidget.html#layout">layout</a>();
}
</pre>
<p> Finally we arrange all five child widgets of <em>this</em> main window
nicely using <a href="#layout()">layout().</a>
<p> <a name="setDefault()"></a>
<p> <pre> void Viewer::setDefault()
{
<a href="qfont.html">QFont</a> font( "Bavaria" );
</pre>
<p> For demonstration purposes on how the <a href="qfont.html">QFont</a> substitution works
we use a non-existant font family, Bavaria, as the default font for
the greetings.
<p> <pre> <a name="x2393"></a> font.<a href="qfont.html#setPointSize">setPointSize</a>( 24 );
</pre>
<p> This font should have a size of 24 points, ...
<p> <pre> <a name="x2396"></a> font.<a href="qfont.html#setWeight">setWeight</a>( QFont::Bold );
</pre>
<p> ... it should be bold, ...
<p> <pre> <a name="x2395"></a> font.<a href="qfont.html#setUnderline">setUnderline</a>( TRUE );
</pre>
<p> ... and the text written should be underlined.
<p> <pre> greetings-><a href="qwidget.html#setFont">setFont</a>( font );
</pre>
<p> Now we ask the <em>greetings</em> widget to use the font <em>font</em>.
<p> As a member of the Bavaria font family is unlikely to
be installed on your machine, run the program and observe
how QFont finds a substitute. Later on we will define
custom substitutions for Bavaria in the <a href="#setFontSubstitutions()">setFontSubstitutions()</a> function.
<p> <pre> showFontInfo( font );
}
</pre>
<p> Finally we use the function <a href="#showFontInfo()">showFontInfo()</a> to display appropriate information
about the current font and how it maybe differs from the one requested.
<p> <a name="setSansSerif()"></a>
<p> <pre> void Viewer::setSansSerif()
{
<a href="qfont.html">QFont</a> font( "Newyork", 18 );
</pre>
<p> The slot to change the greeting font to sans serif
is quite similar to <a href="#setDefault()">setDefault().</a>
Here we save a line of code and define the (non-existant) font family (NewYork)
and size (18 points) at once.
<p> <pre> <a name="x2394"></a> font.<a href="qfont.html#setStyleHint">setStyleHint</a>( QFont::SansSerif );
</pre>
<p> We use a style hint to ask <a href="qfont.html">QFont</a> for a sans serif font
(<em>SansSerif</em> is a member of the QFont::StyleHint enumeration).
<p> As a member of the NewYork family is quite unlikely to be installed
on your computer, QFont will try to follow the style hint and the font size
and use this information to find a replacement font.
<p> <pre> greetings-><a href="qwidget.html#setFont">setFont</a>( font );
</pre>
<p> Finally we apply the requested font to the content of the
<em>greetings</em> textview ...
<p> <pre> showFontInfo( font );
}
</pre>
<p> ... and display the appropriate font information in the <em>fontInfo</em> textview.
<p> <a name="setItalics()"></a>
<p> <pre> void Viewer::setItalics()
{
<a href="qfont.html">QFont</a> font( "Tokyo" );
font.<a href="qfont.html#setPointSize">setPointSize</a>( 32 );
font.<a href="qfont.html#setWeight">setWeight</a>( QFont::Bold );
<a name="x2392"></a> font.<a href="qfont.html#setItalic">setItalic</a>( TRUE );
</pre>
<p> The <a href="#setItalics()">setItalics()</a> slot changes the greetings'
font to a 32 pt bold and italic member of the (again non-existant)
Tokyo family. Note that <a href="#setFontSubstitutions()">setFontSubstitutions()</a> defines a substitution family for Tokyo.
<p> <pre> greetings-><a href="qwidget.html#setFont">setFont</a>( font );
</pre>
<p> We set the font of the <em>greetings</em> textview to <em>font</em>, and ...
<p> <pre> showFontInfo( font );
}
</pre>
<p> ... display the appropriate font information in the <em>fontInfo</em> textview.
<p> <a name="showFontInfo()"></a>
<p> <pre> void Viewer::showFontInfo( <a href="qfont.html">QFont</a> & font )
{
</pre>
<p> Now, how do we show the font information?
<p> <pre> <a href="qfontinfo.html">QFontInfo</a> info( font );
</pre>
<p> First we obtain information about the font that is actually used
when the font <em>font</em> is required, and store it in <em>info</em>.
<p> <pre> <a href="qstring.html">QString</a> messageText;
messageText = "Font requested: \"" +
font.<a href="qfont.html#family">family</a>() + "\" " +
</pre>
<p> Then we start compiling the message that we want to show in the <em>fontInfo</em>
textview.
First, we print out the <em>requested</em> font family name. As we want to
frame the family name with quotation marks, we have to escape the <em>"</em>
character so that it is not confused with the C++ quotation marks
used to terminate strings.
<p> <pre> <a name="x2401"></a><a name="x2391"></a> QString::<a href="qstring.html#number">number</a>( font.<a href="qfont.html#pointSize">pointSize</a>() ) + "pt<BR>" +
</pre>
<p> We obtain the <em>requested</em> font size in points and convert it to
a <a href="qstring.html">QString</a> using <a href="qstring.html#number">QString::number</a>(). Using <em><BR></em>; we add a rich-text
linebreak to the <em>messageText</em> string.
<p> <pre> "Font used: \"" +
</pre>
<p> After we have displayed information about the <em>required</em> font
we want to contrast it with the one <em>actually</em> used.
This is stored in the <a href="qfontinfo.html">QFontInfo</a> <em>info</em> variable.
<p> <pre> <a name="x2398"></a> info.<a href="qfontinfo.html#family">family</a>() + "\" " +
</pre>
<p> First we display the font family, ...
<p> <pre> <a name="x2399"></a> QString::<a href="qstring.html#number">number</a>( info.<a href="qfontinfo.html#pointSize">pointSize</a>() ) + "pt<P>";
</pre>
<p> ... and then we append the actual font size, converted to a QString,
to the message string. The unit abbreviation and a rich-text
paragraph (<em><P></em>) follow.
<p> If custom substitutions are available for the requested <em>font</em>,
we're going to show them as well:
<p> <a name="showFontInfo()_QStringList"></a>
<pre> <a name="x2397"></a><a name="x2388"></a> <a href="qstringlist.html">QStringList</a> substitutions = QFont::<a href="qfont.html#substitutes">substitutes</a>( font.<a href="qfont.html#family">family</a>() );
</pre>
<p> First we store the entire list of substitutes in a string list.
<p> <pre> <a name="x2406"></a> if ( ! substitutions.<a href="qvaluelist.html#isEmpty">isEmpty</a>() ){
</pre>
<p> If it contains at least one substitute ...
<p> <pre> messageText += "The following substitutions exist for " + \
font.<a href="qfont.html#family">family</a>() + ":<UL>";
</pre>
<p> ... we say so in the <em>messageText</em>, ...
<p> <pre> <a name="x2404"></a> QStringList::Iterator i = substitutions.<a href="qvaluelist.html#begin">begin</a>();
</pre>
<p> ... and prepare ourselves to step through the list. For this
purpose we set the list iterator <em>i</em> to the first list member
of the <em>substitutions</em> string list.
<p> <pre> <a name="x2405"></a> while ( i != substitutions.<a href="qvaluelist.html#end">end</a>() ){
</pre>
<p> As long as we haven't reached the last list member ...
<p> <pre> messageText += "<LI>\"" + (* i) + "\"";
</pre>
<p> we add a bullet list entry (<em><LI></em>)
of the current list member (i.e. the font family name
of the substitute), ...
<p> <pre> i++;
}
</pre>
<p> ... and move the iterator one step further.
<a name="setFontSubstitutions()"></a>
<p> <pre> messageText += "</UL>";
</pre>
<p> Finally we add the end-of-bullet-list rich-text tag to the <em>messageText</em>
string.
<p> <pre> } else {
messageText += "No substitutions exist for " + \
font.<a href="qfont.html#family">family</a>() + ".";
}
</pre>
<p> If the substitution list was empty, we make a note about
it in the <em>messageText</em> string.
<p> <pre> fontInfo-><a href="qtextedit.html#setText">setText</a>( messageText );
}
</pre>
<p> Now that we have the <em>messageText</em> string ready we enter it into
the <em>fontInfo</em> textview.
<p> <pre> void Viewer::setFontSubstitutions()
{
</pre>
<p> With this function we finally reveal the secret of how to
define custom substitutions for a font family.
<p> <pre> <a href="qstringlist.html">QStringList</a> substitutes;
</pre>
<p> All we need is a string list.
<p> <pre> <a name="x2403"></a> substitutes.<a href="qvaluelist.html#append">append</a>( "Times" );
substitutes += "Mincho",
substitutes << "Arabic Newspaper" << "crox";
</pre>
<p> In a real world application you will probably stick to one of the above
methods to add strings to a string list. Here all possible ones are outlined
to give you an overview.
<p> After these append operations <em>substitutes</em> consists of four members:
<em>Times</em>, <em>Mincho</em>, <em>Arabic Newspaper</em>, and <em>Crox</em> in this
order. These are the font families that in the first place are searched
for characters the base font does not provide.
<p> <pre> <a name="x2390"></a> QFont::<a href="qfont.html#insertSubstitutions">insertSubstitutions</a>( "Bavaria", substitutes );
</pre>
<p> In <em>Viewer</em> objects, these four families provide a fallback
for the Bavaria font family requested by the <a href="#setDefault()">setDefault()</a> slot.
<p> <pre> <a name="x2389"></a> QFont::<a href="qfont.html#insertSubstitution">insertSubstitution</a>( "Tokyo", "Lucida" );
}
</pre>
<p> For the Tokyo family used in <a href="#setItalics()">setItalics()</a>
we provide only one substitute family, Lucida. Because it is
only one and not many as for Bavaria, we use
<a href="qfont.html#insertSubstitution">QFont::insertSubstitution</a>() instead of <a href="qfont.html#insertSubstitutions">QFont::insertSubstitutions</a>().
<p> If you usually create your GUIs using Qt Designer this walkthrough
has already come to an end. If this is one of your first encounters
with Qt you might however continue with the explanation
of the very simple <a href="#simple-qfont-demo.cpp">main() function.</a>
<p> <a name="layout()"></a>
<p> <pre> <a name="x2408"></a>void Viewer::<a href="qwidget.html#layout">layout</a>()
{
</pre>
<p> This last member function of the <em>Viewer</em> class does not cover
any more <a href="qfont.html">QFont</a> details. All it does is creating a nice automatic
layout for the three push buttons and the two text views.
<p> The best solution for this task is to have the two <a href="qtextview.html">QTextView</a>s
lined up horizontally. The same applies to the <a href="qpushbutton.html">QPushButton</a>s.
Finally both of these layouts are placed together into a vertical
layout container. Qt takes care of the proportions so that everything
looks nice.
<p> <pre> <a href="qhboxlayout.html">QHBoxLayout</a> * textViewContainer = new <a href="qhboxlayout.html">QHBoxLayout</a>();
</pre>
<p> Let's create the first layout that aligns its members horizontally, ...
<p> <pre> <a name="x2386"></a> textViewContainer-><a href="qboxlayout.html#addWidget">addWidget</a>( greetings );
</pre>
<p> ... and add the QTextView with the greetings, ...
<p> <pre> textViewContainer-><a href="qboxlayout.html#addWidget">addWidget</a>( fontInfo );
</pre>
<p> ... as well as the text view with the font information. <em>fontInfo</em> appears
to the right of <em>greetings</em> because it was added later.
<p> <pre> <a href="qhboxlayout.html">QHBoxLayout</a> * buttonContainer = new <a href="qhboxlayout.html">QHBoxLayout</a>();
</pre>
<p> Now we create the second layout for the push buttons.
<p> <pre> buttonContainer-><a href="qboxlayout.html#addWidget">addWidget</a>( defaultButton );
</pre>
<p> <em>defaultButton</em> is placed on the left hand side of the layout, ...
<p> <pre> buttonContainer-><a href="qboxlayout.html#addWidget">addWidget</a>( sansSerifButton );
</pre>
<p> ... <em>sansSerifButton</em> in the middle, ...
<p> <pre> buttonContainer-><a href="qboxlayout.html#addWidget">addWidget</a>( italicsButton );
</pre>
<p> ... and <em>italicsButton</em> on the right hand side.
<p> Unfortunately we face a tiny problem: remember that (a highly unusual
thing to do in a real world application) the labels of the three
buttons are drawn in different fonts. Whilst the automatic layout
accounts for the fact all three buttons have the same width, the uncommon
occurrence of different character heights leads to different button heights.
<p> To make the application window look nice we have to help it a little.
<p> <pre> <a name="x2407"></a> int maxButtonHeight = defaultButton-><a href="qwidget.html#height">height</a>();
if ( sansSerifButton-><a href="qwidget.html#height">height</a>() > maxButtonHeight )
maxButtonHeight = sansSerifButton-><a href="qwidget.html#height">height</a>();
if ( italicsButton-><a href="qwidget.html#height">height</a>() > maxButtonHeight )
maxButtonHeight = italicsButton-><a href="qwidget.html#height">height</a>();
</pre>
<p> By comparing the three button heights we find the largest one
and store it in <em>maxButtonHeight</em>.
<p> <pre> <a name="x2409"></a> defaultButton-><a href="qwidget.html#setFixedHeight">setFixedHeight</a>( maxButtonHeight );
sansSerifButton-><a href="qwidget.html#setFixedHeight">setFixedHeight</a>( maxButtonHeight );
italicsButton-><a href="qwidget.html#setFixedHeight">setFixedHeight</a>( maxButtonHeight );
</pre>
<p> Now we set the height of each button to this maximum value and make sure
that the automatic layout does not change it.
<p> This was the hardest part of the entire layout process. There is one task
left:
<p> <pre> <a href="qvboxlayout.html">QVBoxLayout</a> * container = new <a href="qvboxlayout.html">QVBoxLayout</a>( this );
</pre>
<p> We create a layout that arranges its members vertically.
<p> <pre> <a name="x2385"></a> container-><a href="qboxlayout.html#addLayout">addLayout</a>( textViewContainer );
</pre>
<p> This <em>container</em> layout contains the text views on top, ...
<p> <pre> container-><a href="qboxlayout.html#addLayout">addLayout</a>( buttonContainer );
</pre>
<p> ... and the button row below.
<p> <pre> <a href="qwidget.html#resize">resize</a>( 700, 250 );
}
</pre>
<p> Finally we set the size of the entire main window to a width of 700 pixels
and a height of 250 pixels.
<p> <h3><a name="simple-qfont-demo.cpp">The main program</a></h3>
<p> There is not much to say about the main program.
<p>
<pre> #include "viewer.h"
#include <<a href="qapplication-h.html">qapplication.h</a>>
int main( int argc, char **argv )
{
<a href="qapplication.html">QApplication</a> app( argc, argv );
Viewer * textViewer = new Viewer();
</pre>
<p> We create an instance of the <a href="#viewer.cpp">Viewer</a>
class, ...
<p>
<pre> <a name="x2412"></a> app.<a href="qapplication.html#setMainWidget">setMainWidget</a>( textViewer );
</pre>
<p> ... make it the main widget of the application object <em>app</em>, ...
<p> <pre> <a name="x2413"></a> textViewer-><a href="qwidget.html#show">show</a>();
</pre>
<p> ... display it to the user ...
<p> <pre> <a name="x2411"></a> return app.<a href="qapplication.html#exec">exec</a>();
}
</pre>
<p> ... and enter the application loop. Well done, that was all for today ...
<p> <p>See also <a href="step-by-step-examples.html">Step-by-step Examples</a>.
<!-- eof -->
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<td>Copyright © 2001
<a href="http://www.trolltech.com">Trolltech</a><td><a href="http://www.trolltech.com/trademarks.html">Trademarks</a>
<td align=right><div align=right>Qt version 3.0.2</div>
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