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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>Helpsystem</h1>
<p>
This example demonstrates the different Qt classes
that can be used to provide context sensitive help
in an application.
<p> It uses <a href="qtooltip.html">QToolTip</a> and <a href="qwhatsthis.html">QWhatsThis</a> to provide both static and
dynamic balloon help for the widgets in the application, and
<a href="qtooltipgroup.html">QToolTipGroup</a> to display extended information for each tooltip
in the statusbar. <a href="qassistantclient.html">QAssistantClient</a> is used to display help
pages using Qt Assistant.
<p> The application has a user interface based on a
<a href="qmainwindow.html">QMainWindow</a> with a menubar, statusbar and a toolbar, and uses
a <a href="qtable.html">QTable</a> as the central widget.
<pre> class HeaderToolTip : public <a href="qtooltip.html">QToolTip</a>
{
public:
HeaderToolTip( <a href="qheader.html">QHeader</a> *header, QToolTipGroup *group = 0 );
protected:
void maybeTip ( const <a href="qpoint.html">QPoint</a> &amp;p );
};
</pre>
<p> Two QToolTip subclasses implement dynamic tooltips for
<a href="qheader.html">QHeader</a> and QTable by reimplementing maybeTip(). The
constructors differ from the <a href="qtooltip.html">QToolTip</a> constructor in having a
QHeader and a QTable respectively as the first parameter for
the constructor instead of a <a href="qwidget.html">QWidget</a>. This is because
we want to ensure that only headers and tables can be
passed as arguments. A <a href="qtooltipgroup.html">QToolTipGroup</a> can be provided as the
second argument to show tooltips in, for example a statusbar.
<p> <pre> class TableToolTip : public <a href="qtooltip.html">QToolTip</a>
{
public:
TableToolTip( <a href="qtable.html">QTable</a>* table, QToolTipGroup *group = 0 );
protected:
void maybeTip( const <a href="qpoint.html">QPoint</a> &amp;p );
private:
<a href="qtable.html">QTable</a> *table;
};
</pre>
<p> The TableToolTip class keeps a reference to the <a href="qtable.html">QTable</a>
as a member for easier access of the QTable object later on.
<p>
<pre> HeaderToolTip::HeaderToolTip( <a href="qheader.html">QHeader</a> *header, QToolTipGroup *group )
: <a href="qtooltip.html">QToolTip</a>( header, group )
{
}
</pre>
<p> The HeaderToolTip constructor propagates the parameters
to the <a href="qtooltip.html">QToolTip</a> constructor.
<pre> void HeaderToolTip::<a href="qtooltip.html#maybeTip">maybeTip</a> ( const <a href="qpoint.html">QPoint</a>&amp; p )
{
<a href="qheader.html">QHeader</a> *header = (QHeader*)<a href="qtooltip.html#parentWidget">parentWidget</a>();
int section = 0;
<a name="x2676"></a> if ( header-&gt;<a href="qheader.html#orientation">orientation</a>() == Horizontal )
<a name="x2677"></a><a name="x2675"></a> section = header-&gt;<a href="qheader.html#sectionAt">sectionAt</a>( header-&gt;<a href="qheader.html#offset">offset</a>() + p.<a href="qpoint.html#x">x</a>() );
else
section = header-&gt;<a href="qheader.html#sectionAt">sectionAt</a>( header-&gt;<a href="qheader.html#offset">offset</a>() + p.<a href="qpoint.html#y">y</a>() );
<a name="x2674"></a> <a href="qstring.html">QString</a> tipString = header-&gt;<a href="qheader.html#label">label</a>( section );
<a name="x2678"></a> <a href="qtooltip.html#tip">tip</a>( header-&gt;<a href="qheader.html#sectionRect">sectionRect</a>( section ), tipString, "This is a section in a header" );
}
</pre>
<p> The implementation of maybeTip() uses the <a href="qheader.html">QHeader</a> API
to get the section at the requested position and uses
<a href="qtooltip.html#tip">QToolTip::tip</a>() to display the section's label in a
tooltip. The second string is used by <a href="qtooltipgroup.html">QToolTipGroup</a> and will
show up in the statusbar.
<p> <pre> TableToolTip::TableToolTip( <a href="qtable.html">QTable</a> *tipTable, QToolTipGroup *group )
<a name="x2683"></a>: <a href="qtooltip.html">QToolTip</a>( tipTable-&gt;<a href="qscrollview.html#viewport">viewport</a>(), group ), table( tipTable )
{
}
</pre>
<p> Since <a href="qtable.html">QTable</a> is a <a href="qscrollview.html">QScrollView</a> all user interaction
happens on QTable's viewport() . The TableToolTip
constructor passes the viewport() and the tooltip
group to the <a href="qtooltip.html">QToolTip</a> constructor, and initializes the table
member with the QTable pointer itself.
<pre> <a name="x2684"></a>void TableToolTip::<a href="qtooltip.html#maybeTip">maybeTip</a> ( const <a href="qpoint.html">QPoint</a> &amp;p )
{
<a href="qpoint.html">QPoint</a> cp = table-&gt;viewportToContents( p );
<a name="x2680"></a> int row = table-&gt;rowAt( cp.<a href="qpoint.html#y">y</a>() );
<a name="x2679"></a> int col = table-&gt;columnAt( cp.<a href="qpoint.html#x">x</a>() );
<a href="qstring.html">QString</a> tipString = table-&gt;text( row, col );
<a href="qrect.html">QRect</a> cr = table-&gt;cellGeometry( row, col );
</pre>
<p> The implementation of maybeTip() uses the QTable API
to get information about the cell at the requested position.
The <a href="qtable.html">QTable</a> API expects contents coordinates, and since the
requested point is relative to the viewport we need to translate
the coordinates before we can use QTable's functions.
<pre> <a name="x2682"></a><a name="x2681"></a> cr.<a href="qrect.html#moveTopLeft">moveTopLeft</a>( table-&gt;contentsToViewport( cr.<a href="qrect.html#topLeft">topLeft</a>() ) );
<a href="qtooltip.html#tip">tip</a>( cr, tipString, "This is a cell in a table" );
}
</pre>
<p> We translate the cell's geometry back to viewport coordinates
so that the tooltip disappears when the mouse cursor leaves
the cell, and use <a href="qtooltip.html#tip">QToolTip::tip</a>() to display the cell's label
in a tooltip and to provide text for the <a href="qtooltipgroup.html">QToolTipGroup</a> as before.
<pre> class WhatsThis : public <a href="qobject.html">QObject</a>, public QWhatsThis
{
<a href="metaobjects.html#Q_OBJECT">Q_OBJECT</a>
public:
WhatsThis( <a href="qwidget.html">QWidget</a> *w, QWidget *watch = 0 );
bool clicked( const <a href="qstring.html">QString</a> &amp;link );
<a href="qwidget.html">QWidget</a> *parentWidget() const;
signals:
void linkClicked( const <a href="qstring.html">QString</a> &amp;link );
private:
<a href="qwidget.html">QWidget</a> *widget;
};
</pre>
<p> The WhatsThis class is a subclass of both <a href="qobject.html">QObject</a> and
<a href="qwhatsthis.html">QWhatsThis</a> and serves as a base class for the HeaderWhatsThis
and TableWhatsThis classes. <a href="#footnote1"><sup>(1)</sup></a><a name="footnote-call1"></a> WhatsThis
reimplements clicked() which will be called when the user clicks
inside the "What's this?" window. It also declares a signal
linkClicked() which will be emitted when a hyperlink is clicked.
<pre> WhatsThis::WhatsThis( <a href="qwidget.html">QWidget</a> *w, QWidget *watch )
: <a href="qwhatsthis.html">QWhatsThis</a>( watch ? watch : w ), widget( w )
{
}
</pre>
<p> The WhatsThis constructor takes two parameters, the first is the
widget we want to provide WhatsThis for, and the second is the
one which receives the events. Normally this is the same widget,
but some widgets, like <a href="qtable.html">QTable</a>, are more complex and have a
viewport() widget which receives the events. If such a widget
is passed to the constructor it will propagate the parameter to
the QWhatsThis constructor and store the <a href="qwidget.html">QWidget</a> pointer itself
in it's member variable to allow easier use of the QWidget API
later on.
<pre> bool WhatsThis::clicked( const <a href="qstring.html">QString</a> &amp;link )
{
if ( !link.<a href="qstring.html#isEmpty">isEmpty</a>() )
emit linkClicked( link );
return TRUE;
}
</pre>
<p> The implementation of clicked() emits the linkClicked() signal
if a hyperlink has been clicked.
<pre> class HeaderWhatsThis : public WhatsThis
{
public:
HeaderWhatsThis( <a href="qheader.html">QHeader</a> *h );
<a href="qstring.html">QString</a> text( const <a href="qpoint.html">QPoint</a> &amp;p );
};
</pre>
<p> <pre> class TableWhatsThis : public WhatsThis
{
public:
TableWhatsThis( <a href="qtable.html">QTable</a> *t );
<a href="qstring.html">QString</a> text( const <a href="qpoint.html">QPoint</a> &amp;p );
};
</pre>
<p>
<p> The HeaderWhatsThis and TableWhatsThis classes reimplement
text() to make it possible to return texts depending on the
mouse click's position. All the other functionality is
already provided by the generic WhatsThis base class. We ensure
type safety here in the same manner as in the tooltip classes.
<pre> HeaderWhatsThis::HeaderWhatsThis( <a href="qheader.html">QHeader</a> *h )
: WhatsThis( h )
{
}
</pre>
<p> The HeaderWhatsThis constructor propagates the parameter to the
WhatsThis constructor.
<pre> QString HeaderWhatsThis::text( const <a href="qpoint.html">QPoint</a> &amp;p )
{
<a href="qheader.html">QHeader</a> *header = (QHeader*)parentWidget();
<a href="qstring.html">QString</a> orient;
int section;
if ( header-&gt;<a href="qheader.html#orientation">orientation</a>() == QObject::Horizontal ) {
orient = "horizontal";
section = header-&gt;<a href="qheader.html#sectionAt">sectionAt</a>( p.<a href="qpoint.html#x">x</a>() );
} else {
orient = "vertical";
section = header-&gt;<a href="qheader.html#sectionAt">sectionAt</a>( p.<a href="qpoint.html#y">y</a>() );
}
if( section == -1 )
return "This is empty space.";
<a href="qstring.html">QString</a> docsPath = QDir("../../doc").absPath();
return QString("This is section number %1 in the %2 &lt;a href=%2/html/qheader.html&gt;header&lt;/a&gt;.").
arg(section + 1).
arg(orient).
arg(docsPath);
}
</pre>
<p> The implementation of text() uses the <a href="qheader.html">QHeader</a> API to determine
whether we have a horizontal or a vertical header and returns
a string which states the header's orientation and section.
<a href="#footnote2"><sup>(2)</sup></a><a name="footnote-call2"></a>
<pre> TableWhatsThis::TableWhatsThis( <a href="qtable.html">QTable</a> *t )
: WhatsThis( t, t-&gt;<a href="qscrollview.html#viewport">viewport</a>() )
{
}
</pre>
<p> Since <a href="qtable.html">QTable</a> is a scrollview and has a viewport() which receives
the events, we propagate the table itself and the table's
viewport() to the WhatsThis constructor.
<pre> QString TableWhatsThis::text( const <a href="qpoint.html">QPoint</a> &amp;p )
{
<a href="qtable.html">QTable</a> *table = (QTable*)parentWidget();
<a href="qpoint.html">QPoint</a> cp = table-&gt;<a href="qscrollview.html#viewportToContents">viewportToContents</a>( p );
int row = table-&gt;<a href="qtable.html#rowAt">rowAt</a>( cp.<a href="qpoint.html#y">y</a>() );
int col = table-&gt;<a href="qtable.html#columnAt">columnAt</a>( cp.<a href="qpoint.html#x">x</a>() );
if ( row == -1 || col == -1 )
return "This is empty space.";
<a href="qtableitem.html">QTableItem</a>* i = table-&gt;<a href="qtable.html#item">item</a>( row,col );
if ( !i )
return "This is an empty cell.";
<a href="qstring.html">QString</a> docsPath = QDir("../../doc").absPath();
if ( QTableItem::RTTI == i-&gt;<a href="qtableitem.html#rtti">rtti</a>() ) {
return QString("This is a &lt;a href=%1/html/qtableitem.html&gt;QTableItem&lt;/a&gt;.").
arg(docsPath);
} else if ( QComboTableItem::RTTI == i-&gt;<a href="qtableitem.html#rtti">rtti</a>() ) {
return QString("This is a &lt;a href=%1/html/qcombotableitem.html&gt;QComboTableItem&lt;/a&gt;."
"&lt;br&gt;It can be used to provide multiple-choice items in a table.").
arg(docsPath);
} else if ( QCheckTableItem::RTTI == i-&gt;<a href="qtableitem.html#rtti">rtti</a>() ) {
return QString("This is a &lt;a href=%1/html/qchecktableitem.html&gt;QCheckTableItem&lt;/a&gt;."
"&lt;br&gt;It provide &lt;a href=%1/html/qcheckbox.html&gt;checkboxes&lt;/a&gt; in tables.").
arg(docsPath).arg(docsPath);
}
return "This is a user defined table item.";
}
</pre>
<p> The implementation of text() uses the <a href="qtable.html">QTable</a> API to get
information about the cell at the requested position.
The QTable API expects contents coordinates, so we need to
translate the point as shown earlier for the tooltip classes.
We use the rtti() function to figure out the item's type
and return a string accordingly.
<p>
<pre> class MainWindow : public <a href="qmainwindow.html">QMainWindow</a>
{
Q_OBJECT
public:
MainWindow();
~MainWindow();
public slots:
void assistantSlot();
private:
HeaderToolTip *horizontalTip;
HeaderToolTip *verticalTip;
TableToolTip *cellTip;
<a href="qassistantclient.html">QAssistantClient</a> *assistant;
};
</pre>
<p> A <a href="qmainwindow.html">QMainWindow</a> is used to create a user interface that uses the
above classes in addition to Qt Assistant to provide context
sensitive help in the application.
<p> The MainWindow class declares a slot called assistantSlot()
which creates an instance of Qt Assistant when it is called.
The class keeps references to the tooltip classes as members
because they are not QObjects and need to be deleted explicitly.
The class has a reference to <a href="qassistantclient.html">QAssistantClient</a> as a
member as well, to allow easier access to Qt Assistant later on.
<p>
<pre> MainWindow::MainWindow()
{
<a href="qmainwindow.html#statusBar">statusBar</a>();
assistant = new <a href="qassistantclient.html">QAssistantClient</a>( QDir("../../bin").absPath(), this );
</pre>
<p> The MainWindow constructor creates an instance of
QAssistantClient using <a href="qstring.html#QString-null">QString::null</a> as the first argument
so that the system path is used.
<pre> <a href="qtable.html">QTable</a>* table = new <a href="qtable.html">QTable</a>( 2, 3, this );
<a href="qmainwindow.html#setCentralWidget">setCentralWidget</a>( table );
// populate table
<a href="qstringlist.html">QStringList</a> comboEntries;
comboEntries &lt;&lt; "one" &lt;&lt; "two" &lt;&lt; "three" &lt;&lt; "four";
<a href="qcombotableitem.html">QComboTableItem</a>* comboItem1 = new <a href="qcombotableitem.html">QComboTableItem</a>( table, comboEntries );
<a href="qcombotableitem.html">QComboTableItem</a>* comboItem2 = new <a href="qcombotableitem.html">QComboTableItem</a>( table, comboEntries );
<a href="qchecktableitem.html">QCheckTableItem</a>* checkItem1 = new <a href="qchecktableitem.html">QCheckTableItem</a>( table, "Check me" );
<a href="qchecktableitem.html">QCheckTableItem</a>* checkItem2 = new <a href="qchecktableitem.html">QCheckTableItem</a>( table, "Check me" );
<a name="x2691"></a> table-&gt;<a href="qtable.html#setItem">setItem</a>( 0, 0, comboItem1 );
table-&gt;<a href="qtable.html#setItem">setItem</a>( 1, 0, comboItem2 );
table-&gt;<a href="qtable.html#setItem">setItem</a>( 1, 1, checkItem1 );
table-&gt;<a href="qtable.html#setItem">setItem</a>( 0, 1, checkItem2 );
<a name="x2692"></a> table-&gt;<a href="qtable.html#setText">setText</a>( 1, 2, "Text" );
table-&gt;<a href="qtable.html#horizontalHeader">horizontalHeader</a>()-&gt;setLabel( 0, " Combos" );
table-&gt;<a href="qtable.html#horizontalHeader">horizontalHeader</a>()-&gt;setLabel( 1, "Checkboxes" );
table-&gt;<a href="qtable.html#verticalHeader">verticalHeader</a>()-&gt;setLabel( 0, "1" );
table-&gt;<a href="qtable.html#verticalHeader">verticalHeader</a>()-&gt;setLabel( 1, "2" );
// populate menubar
<a href="qpopupmenu.html">QPopupMenu</a>* fileMenu = new <a href="qpopupmenu.html">QPopupMenu</a>( this );
<a href="qpopupmenu.html">QPopupMenu</a>* helpMenu = new <a href="qpopupmenu.html">QPopupMenu</a>( this );
<a href="qmainwindow.html#menuBar">menuBar</a>()-&gt;insertItem( "&amp;File", fileMenu );
<a href="qmainwindow.html#menuBar">menuBar</a>()-&gt;insertItem( "&amp;Help", helpMenu );
int fileId = fileMenu-&gt;<a href="qmenudata.html#insertItem">insertItem</a>( "E&amp;xit", this, SLOT(<a href="qwidget.html#close">close</a>()) );
int helpId = helpMenu-&gt;<a href="qmenudata.html#insertItem">insertItem</a>( "Open Assistant", this, SLOT(assistantSlot()) );
// populate toolbar
<a href="qtoolbar.html">QToolBar</a>* toolbar = new <a href="qtoolbar.html">QToolBar</a>( this );
<a href="qtoolbutton.html">QToolButton</a>* assistantButton = new <a href="qtoolbutton.html">QToolButton</a>( toolbar );
<a name="x2694"></a> assistantButton-&gt;<a href="qtoolbutton.html#setIconSet">setIconSet</a>( QPixmap("appicon.png") );
</pre>
<p> A <a href="qtable.html">QTable</a> is used as the central widget and the table, the menus
and the toolbar are populated.
<pre> <a name="x2699"></a> QWhatsThis::<a href="qwhatsthis.html#whatsThisButton">whatsThisButton</a>( toolbar );
</pre>
<p> The static function whatsThisButton() creates a <a href="qtoolbutton.html">QToolButton</a>
which will enter "What's this?" mode when clicked.
<pre> //create tooltipgroup
<a href="qtooltipgroup.html">QToolTipGroup</a> * tipGroup = new <a href="qtooltipgroup.html">QToolTipGroup</a>( this );
<a name="x2697"></a> <a href="qobject.html#connect">connect</a>( tipGroup, SIGNAL(<a href="qtooltipgroup.html#showTip">showTip</a>(const <a href="qstring.html">QString</a>&amp;)), statusBar(),
SLOT(message(const <a href="qstring.html">QString</a>&amp;)) );
<a name="x2696"></a> <a href="qobject.html#connect">connect</a>( tipGroup, SIGNAL(<a href="qtooltipgroup.html#removeTip">removeTip</a>()), statusBar(), SLOT(clear()) );
</pre>
<p> A <a href="qtooltipgroup.html">QToolTipGroup</a> is created and will show and remove tooltips
in the statusbar as the tooltips are displayed on the widgets.
<pre> // set up tooltips
<a name="x2695"></a> QToolTip::<a href="qtooltip.html#add">add</a>( assistantButton, tr ("Open Assistant"), tipGroup, "Opens Qt Assistant" );
<a name="x2690"></a> horizontalTip = new HeaderToolTip( table-&gt;<a href="qtable.html#horizontalHeader">horizontalHeader</a>(), tipGroup );
<a name="x2693"></a> verticalTip = new HeaderToolTip( table-&gt;<a href="qtable.html#verticalHeader">verticalHeader</a>(), tipGroup );
cellTip = new TableToolTip( table, tipGroup );
</pre>
<p> The tooltips are set up. The static function add() sets up a
tooltip on the Assistant toolbutton. Tooltip objects are created
using the <a href="qtooltip.html">QToolTip</a> subclasses, the constructor's first parameter
specifies the widget we want to add dynamic tooltips for and the
second argument specifies the <a href="qtooltipgroup.html">QToolTipGroup</a> they should belong
to.
<pre> // set up whats this
<a name="x2698"></a> QWhatsThis::<a href="qwhatsthis.html#add">add</a> ( assistantButton, "This is a toolbutton which opens Assistant" );
HeaderWhatsThis *horizontalWhatsThis = new HeaderWhatsThis( table-&gt;<a href="qtable.html#horizontalHeader">horizontalHeader</a>() );
HeaderWhatsThis *verticalWhatsThis = new HeaderWhatsThis( table-&gt;<a href="qtable.html#verticalHeader">verticalHeader</a>() );
TableWhatsThis *cellWhatsThis = new TableWhatsThis( table );
<a name="x2689"></a> fileMenu-&gt;<a href="qmenudata.html#setWhatsThis">setWhatsThis</a>( fileId, "Click here to exit the application" );
helpMenu-&gt;<a href="qmenudata.html#setWhatsThis">setWhatsThis</a>( helpId, "Click here to open Assistant" );
</pre>
<p> The WhatsThis help is set up. The static function add() adds
What's This? help for the toolbutton which opens Assistant.
Instances of the two WhatsThis subclasses are created for the
headers and the table. What's This? help is also added for the
menu items.
<pre> // connections
<a href="qobject.html#connect">connect</a>( assistantButton, SIGNAL(<a href="qbutton.html#clicked">clicked</a>()), this, SLOT(assistantSlot()) );
<a href="qobject.html#connect">connect</a>( horizontalWhatsThis, SIGNAL(linkClicked(const <a href="qstring.html">QString</a>&amp;)), assistant,
SLOT(<a href="qassistantclient.html#showPage">showPage</a>(const <a href="qstring.html">QString</a>&amp;)) );
<a href="qobject.html#connect">connect</a>( verticalWhatsThis, SIGNAL(linkClicked(const <a href="qstring.html">QString</a>&amp;)), assistant,
SLOT(<a href="qassistantclient.html#showPage">showPage</a>(const <a href="qstring.html">QString</a>&amp;)) );
<a href="qobject.html#connect">connect</a>( cellWhatsThis, SIGNAL(linkClicked(const <a href="qstring.html">QString</a>&amp;)), assistant,
SLOT(<a href="qassistantclient.html#showPage">showPage</a>(const <a href="qstring.html">QString</a>&amp;)) );
}
</pre>
<p> Signals and slots are connected, so that the relevant pages will
be displayed in Qt Assistant when clicking on a hyperlink or on
the assistant button.
<pre> MainWindow::~MainWindow()
{
delete horizontalTip;
delete verticalTip;
delete cellTip;
}
</pre>
<p> The destructor deletes the tooltips. We need to delete the
tooltips explicitly since <a href="qtooltip.html">QToolTip</a> is, as mentioned above, not
a subclass of <a href="qobject.html">QObject</a> and the instances of QToolTip not will be
deleted when the widget is deleted.
<pre> void MainWindow::assistantSlot()
{
<a href="qstring.html">QString</a> docsPath = QDir("../../doc").absPath();
<a name="x2686"></a> assistant-&gt;<a href="qassistantclient.html#showPage">showPage</a>( QString("%1/html/qassistantclient.html").arg(docsPath) );
}
</pre>
<p> The assistantSlot() uses applicationDirPath() to find the
location of the documentation files and shows the specified page
in Qt Assistant.
<pre> #include &lt;<a href="qapplication-h.html">qapplication.h</a>&gt;
#include "mainwindow.h"
int main( int argc, char** argv )
{
<a href="qapplication.html">QApplication</a> app( argc, argv );
MainWindow main;
main.<a href="qwidget.html#show">show</a>();
<a name="x2701"></a> app.<a href="qapplication.html#setMainWidget">setMainWidget</a>( &amp;main );
<a name="x2700"></a> return app.<a href="qapplication.html#exec">exec</a>();
}
</pre>
<p> The main function is a standard implementation opening
the application main window.
<p> To build the example go to the helpsystem directory
(QTDIR/examples/helpsystem) run qmake to generate the makefile,
and use the make tool to build the library.
<hr>
<ol> <li><a name="footnote1"></a>
Note that <a href="moc.html#moc">moc</a> requires that <a href="qobject.html">QObject</a>
is the first base class. <a href="#footnote-call1">Back...</a> <li><a name="footnote2"></a>
Note that we have to explicitly scope the orientation
(QObject or <a href="qwhatsthis.html">QWhatsThis</a>) since HeaderWhatsThis uses multiple
inheritance. <a href="#footnote-call2">Back...</a></ol>
</hr><p>See also <a href="examples.html">Examples</a>.
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<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>
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