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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>QDialog Class Reference</h1>
<p>The QDialog class is the base class of dialog windows.
<a href="#details">More...</a>
<p><tt>#include &lt;<a href="qdialog-h.html">qdialog.h</a>&gt;</tt>
<p>Inherits <a href="qwidget.html">QWidget</a>.
<p>Inherited by <a href="qcolordialog.html">QColorDialog</a>, <a href="qerrormessage.html">QErrorMessage</a>, <a href="qfiledialog.html">QFileDialog</a>, <a href="qfontdialog.html">QFontDialog</a>, <a href="qinputdialog.html">QInputDialog</a>, <a href="qmessagebox.html">QMessageBox</a>, <a href="qmotifdialog.html">QMotifDialog</a>, <a href="qprogressdialog.html">QProgressDialog</a>, <a href="qtabdialog.html">QTabDialog</a>, and <a href="qwizard.html">QWizard</a>.
<p><a href="qdialog-members.html">List of all member functions.</a>
<h2>Public Members</h2>
<ul>
<li class=fn>explicit <a href="#QDialog"><b>QDialog</b></a> ( QWidget&nbsp;*&nbsp;parent = 0, const&nbsp;char&nbsp;*&nbsp;name = 0, bool&nbsp;modal = FALSE, WFlags&nbsp;f = 0 )</li>
<li class=fn><a href="#~QDialog"><b>~QDialog</b></a> ()</li>
<li class=fn>enum <a href="#DialogCode-enum"><b>DialogCode</b></a> { Rejected, Accepted }</li>
<li class=fn>int <a href="#result"><b>result</b></a> () const</li>
<li class=fn>virtual void <a href="#show"><b>show</b></a> ()</li>
<li class=fn>void <a href="#setOrientation"><b>setOrientation</b></a> ( Orientation&nbsp;orientation )</li>
<li class=fn>Orientation <a href="#orientation"><b>orientation</b></a> () const</li>
<li class=fn>void <a href="#setExtension"><b>setExtension</b></a> ( QWidget&nbsp;*&nbsp;extension )</li>
<li class=fn>QWidget * <a href="#extension"><b>extension</b></a> () const</li>
<li class=fn>void <a href="#setSizeGripEnabled"><b>setSizeGripEnabled</b></a> ( bool )</li>
<li class=fn>bool <a href="#isSizeGripEnabled"><b>isSizeGripEnabled</b></a> () const</li>
<li class=fn>void <a href="#setModal"><b>setModal</b></a> ( bool&nbsp;modal )</li>
<li class=fn>bool <a href="#isModal"><b>isModal</b></a> () const</li>
</ul>
<h2>Public Slots</h2>
<ul>
<li class=fn>int <a href="#exec"><b>exec</b></a> ()</li>
</ul>
<h2>Properties</h2>
<ul>
<li class=fn>bool <a href="#modal-prop"><b>modal</b></a>&nbsp;- whether show() should pop up the dialog as modal or modeless</li>
<li class=fn>bool <a href="#sizeGripEnabled-prop"><b>sizeGripEnabled</b></a>&nbsp;- whether the size grip is enabled</li>
</ul>
<h2>Protected Members</h2>
<ul>
<li class=fn>void <a href="#setResult"><b>setResult</b></a> ( int&nbsp;i )</li>
</ul>
<h2>Protected Slots</h2>
<ul>
<li class=fn>virtual void <a href="#done"><b>done</b></a> ( int&nbsp;r )</li>
<li class=fn>virtual void <a href="#accept"><b>accept</b></a> ()</li>
<li class=fn>virtual void <a href="#reject"><b>reject</b></a> ()</li>
<li class=fn>void <a href="#showExtension"><b>showExtension</b></a> ( bool&nbsp;showIt )</li>
</ul>
<hr><a name="details"></a><h2>Detailed Description</h2>
The QDialog class is the base class of dialog windows.
<p>
<p> A dialog window is a top-level window mostly used for short-term
tasks and brief communications with the user. QDialogs may be
modal or modeless. QDialogs support <a href="#extensibility">extensibility</a> and can provide a <a href="#return">return
value</a>. They can have <a href="#default">default
buttons</a>. QDialogs can also have a <a href="qsizegrip.html">QSizeGrip</a> in their
lower-right corner, using <a href="#setSizeGripEnabled">setSizeGripEnabled</a>().
<p> Note that QDialog uses the parent widget slightly differently from
other classes in Qt. A dialog is always a top-level widget, but if
it has a parent, its default location is centered on top of the
parent's top-level widget (if it is not top-level itself). It will
also share the parent's taskbar entry.
<p> <a name="modal"></a>
<h3> Modal Dialogs
</h3>
<a name="1"></a><p> A <b>modal</b> dialog is a dialog that blocks input to other
visible windows in the same application. Users must finish
interacting with the dialog and close it before they can access
any other window in the application. Dialogs that are used to
request a file name from the user or that are used to set
application preferences are usually modal.
<p> The most common way to display a modal dialog is to call its
<a href="#exec">exec</a>() function. When the user closes the dialog, exec() will
provide a useful <a href="#return">return value</a>. Typically we
connect a default button, e.g. "OK", to the <a href="#accept">accept</a>() slot and a
"Cancel" button to the <a href="#reject">reject</a>() slot, to get the dialog to close
and return the appropriate value. Alternatively you can connect to
the <a href="#done">done</a>() slot, passing it <a href="#DialogCode-enum">Accepted</a> or <a href="#DialogCode-enum">Rejected</a>.
<p> An alternative is to call <a href="#setModal">setModal</a>(TRUE), then <a href="#show">show</a>(). Unlike
exec(), show() returns control to the caller immediately. Calling
setModal(TRUE) is especially useful for progress dialogs, where
the user must have the ability to interact with the dialog, e.g.
to cancel a long running operation. If you use show() and
setModal(TRUE) together you must call
<a href="qapplication.html#processEvents">QApplication::processEvents</a>() periodically during processing to
enable the user to interact with the dialog. (See <a href="qprogressdialog.html">QProgressDialog</a>.)
<p> <a name="modeless"></a>
<h3> Modeless Dialogs
</h3>
<a name="1-1"></a><p> A <b>modeless</b> dialog is a dialog that operates
independently of other windows in the same application. Find and
replace dialogs in word-processors are often modeless to allow the
user to interact with both the application's main window and with
the dialog.
<p> Modeless dialogs are displayed using show(), which returns control
to the caller immediately.
<p> <a name="default"></a>
<h3> Default button
</h3>
<a name="1-2"></a><p> A dialog's <em>default</em> button is the button that's pressed when the
user presses Enter (Return). This button is used to signify that
the user accepts the dialog's settings and wants to close the
dialog. Use <a href="qpushbutton.html#setDefault">QPushButton::setDefault</a>(), <a href="qpushbutton.html#isDefault">QPushButton::isDefault</a>()
and <a href="qpushbutton.html#autoDefault">QPushButton::autoDefault</a>() to set and control the dialog's
default button.
<p> <a name="escapekey"></a>
<h3> Escape Key
</h3>
<a name="1-3"></a><p> If the user presses the Esc key in a dialog, <a href="#reject">QDialog::reject</a>()
will be called. This will cause the window to close: the <a href="qcloseevent.html">closeEvent</a> cannot be <a href="qcloseevent.html#ignore">ignored</a>.
<p> <a name="extensibility"></a>
<h3> Extensibility
</h3>
<a name="1-4"></a><p> Extensibility is the ability to show the dialog in two ways: a
partial dialog that shows the most commonly used options, and a
full dialog that shows all the options. Typically an extensible
dialog will initially appear as a partial dialog, but with a
"More" toggle button. If the user presses the "More" button down,
the full dialog will appear. The extension widget will be resized
to its <a href="qwidget.html#sizeHint">sizeHint</a>(). If orientation is <a href="qt.html#Orientation-enum">Horizontal</a> the extension
widget's <a href="qwidget.html#height">height</a>() will be expanded to the height() of the dialog.
If the orientation is <a href="qt.html#Orientation-enum">Vertical</a> the extension widget's <a href="qwidget.html#width">width</a>()
will be expanded to the width() of the dialog. Extensibility is
controlled with <a href="#setExtension">setExtension</a>(), <a href="#setOrientation">setOrientation</a>() and
<a href="#showExtension">showExtension</a>().
<p> <a name="return"></a>
<h3> Return value (modal dialogs)
</h3>
<a name="1-5"></a><p> Modal dialogs are often used in situations where a return value is
required, e.g. to indicate whether the user pressed "OK" or
"Cancel". A dialog can be closed by calling the <a href="#accept">accept</a>() or the
<a href="#reject">reject</a>() slots, and <a href="#exec">exec</a>() will return <a href="#DialogCode-enum">Accepted</a> or <a href="#DialogCode-enum">Rejected</a>
as appropriate. The exec() call returns the result of the dialog.
The result is also available from <a href="#result">result</a>() if the dialog has not
been destroyed. If the <a href="qt.html#WidgetFlags-enum">WDestructiveClose</a> flag is set, the
dialog is deleted after exec() returns.
<p> <a name="examples"></a>
<h3> Examples
</h3>
<a name="1-6"></a><p> A modal dialog.
<p>
<pre> <a href="qfiledialog.html">QFileDialog</a> *dlg = new <a href="qfiledialog.html">QFileDialog</a>( workingDirectory,
<a href="qstring.html#QString-null">QString::null</a>, 0, 0, TRUE );
<a name="x2130"></a> dlg-&gt;<a href="qwidget.html#setCaption">setCaption</a>( QFileDialog::<a href="qobject.html#tr">tr</a>( "Open" ) );
<a name="x2128"></a> dlg-&gt;<a href="qfiledialog.html#setMode">setMode</a>( QFileDialog::ExistingFile );
<a href="qstring.html">QString</a> result;
<a name="x2126"></a> if ( dlg-&gt;<a href="#exec">exec</a>() == QDialog::<a href="#DialogCode-enum">Accepted</a> ) {
<a name="x2127"></a> result = dlg-&gt;<a href="qfiledialog.html#selectedFile">selectedFile</a>();
<a name="x2129"></a> workingDirectory = dlg-&gt;<a href="qfiledialog.html#url">url</a>();
}
delete dlg;
return result;
</pre>
<p> A modeless dialog. After the <a href="#show">show</a>() call, control returns to the main
event loop.
<pre> int main( int argc, char **argv )
{
<a href="qapplication.html">QApplication</a> a( argc, argv );
</pre><pre> int scale = 10;
</pre><pre> LifeDialog *life = new LifeDialog( scale );
<a name="x2133"></a> a.<a href="qapplication.html#setMainWidget">setMainWidget</a>( life );
<a name="x2134"></a> life-&gt;<a href="qwidget.html#setCaption">setCaption</a>("Qt Example - Life");
<a name="x2135"></a> life-&gt;<a href="qwidget.html#show">show</a>();
</pre><pre> <a name="x2132"></a> return a.<a href="qapplication.html#exec">exec</a>();
}
</pre>
<p> <p>See also <a href="qtabdialog.html">QTabDialog</a>, <a href="qwidget.html">QWidget</a>, <a href="qprogressdialog.html">QProgressDialog</a>, <a href="guibooks.html#fowler">GUI Design Handbook: Dialogs, Standard</a>, <a href="abstractwidgets.html">Abstract Widget Classes</a>, and <a href="dialogs.html">Dialog Classes</a>.
<hr><h2>Member Type Documentation</h2>
<h3 class=fn><a name="DialogCode-enum"></a>QDialog::DialogCode</h3>
<p> The value returned by a modal dialog.
<ul>
<li><tt>QDialog::Accepted</tt>
<li><tt>QDialog::Rejected</tt>
</ul><p>
<hr><h2>Member Function Documentation</h2>
<h3 class=fn>explicit <a name="QDialog"></a>QDialog::QDialog ( <a href="qwidget.html">QWidget</a>&nbsp;*&nbsp;parent = 0, const&nbsp;char&nbsp;*&nbsp;name = 0, bool&nbsp;modal = FALSE, WFlags&nbsp;f = 0 )
</h3>
Constructs a dialog called <em>name</em>, with parent <em>parent</em>.
<p> A dialog is always a top-level widget, but if it has a parent, its
default location is centered on top of the parent. It will also
share the parent's taskbar entry.
<p> The widget flags <em>f</em> are passed on to the <a href="qwidget.html">QWidget</a> constructor.
If, for example, you don't want a What's This button in the titlebar
of the dialog, pass WStyle_Customize | WStyle_NormalBorder |
WStyle_Title | WStyle_SysMenu in <em>f</em>.
<p> <b>Warning:</b> In Qt 3.2, the <em>modal</em> flag is obsolete. There is now a
<a href="#setModal">setModal</a>() function that can be used for obtaining a modal behavior
when calling <a href="#show">show</a>(). This is rarely needed, because modal dialogs
are usually invoked using <a href="#exec">exec</a>(), which ignores the <em>modal</em> flag.
<p> <p>See also <a href="qwidget.html#setWFlags">QWidget::setWFlags</a>() and <a href="qt.html#WidgetFlags-enum">Qt::WidgetFlags</a>.
<h3 class=fn><a name="~QDialog"></a>QDialog::~QDialog ()
</h3>
Destroys the QDialog, deleting all its children.
<h3 class=fn>void <a name="accept"></a>QDialog::accept ()<tt> [virtual protected slot]</tt>
</h3>
Hides the modal dialog and sets the result code to <a href="#DialogCode-enum">Accepted</a>.
<p> <p>See also <a href="#reject">reject</a>() and <a href="#done">done</a>().
<p>Examples: <a href="tutorial2-08.html#x2604">chart/setdataform.cpp</a> and <a href="distributor-example.html#x2654">distributor/distributor.ui.h</a>.
<h3 class=fn>void <a name="done"></a>QDialog::done ( int&nbsp;r )<tt> [virtual protected slot]</tt>
</h3> Closes the dialog and sets its result code to <em>r</em>. If this dialog
is shown with <a href="#exec">exec</a>(), <a href="#done">done</a>() causes the local event loop to finish,
and exec() to return <em>r</em>.
<p> As with <a href="qwidget.html#close">QWidget::close</a>(), done() deletes the dialog if the <a href="qt.html#WidgetFlags-enum">WDestructiveClose</a> flag is set. If the dialog is the application's
main widget, the application terminates. If the dialog is the
last window closed, the <a href="qapplication.html#lastWindowClosed">QApplication::lastWindowClosed</a>() signal is
emitted.
<p> <p>See also <a href="#accept">accept</a>(), <a href="#reject">reject</a>(), <a href="qapplication.html#mainWidget">QApplication::mainWidget</a>(), and <a href="qapplication.html#quit">QApplication::quit</a>().
<h3 class=fn>int <a name="exec"></a>QDialog::exec ()<tt> [slot]</tt>
</h3>
Shows the dialog as a <a href="#modal">modal</a> dialog,
blocking until the user closes it. The function returns a <a href="#DialogCode-enum">DialogCode</a> result.
<p> Users cannot interact with any other window in the same
application until they close the dialog.
<p> <p>See also <a href="#show">show</a>() and <a href="#result">result</a>().
<p>Examples: <a href="canvas-chart-example.html#x2877">chart/chartform.cpp</a>, <a href="motif-dialog-example.html#x2706">dialog/mainwindow.cpp</a>, <a href="i18n-example.html#x1936">i18n/main.cpp</a>, <a href="ftpclient-example.html#x739">network/ftpclient/ftpmainwindow.ui.h</a>, <a href="qdialog.html#x2126">network/networkprotocol/view.cpp</a>, <a href="qdir-example.html#x1812">qdir/qdir.cpp</a>, and <a href="wizard-example.html#x16">wizard/main.cpp</a>.
<h3 class=fn><a href="qwidget.html">QWidget</a>&nbsp;* <a name="extension"></a>QDialog::extension () const
</h3>
Returns the dialog's extension or 0 if no extension has been
defined.
<p> <p>See also <a href="#setExtension">setExtension</a>().
<h3 class=fn>bool <a name="isModal"></a>QDialog::isModal () const
</h3><p>Returns TRUE if <a href="#show">show</a>() should pop up the dialog as modal or modeless; otherwise returns FALSE.
See the <a href="qdialog.html#modal-prop">"modal"</a> property for details.
<h3 class=fn>bool <a name="isSizeGripEnabled"></a>QDialog::isSizeGripEnabled () const
</h3><p>Returns TRUE if the size grip is enabled; otherwise returns FALSE.
See the <a href="qdialog.html#sizeGripEnabled-prop">"sizeGripEnabled"</a> property for details.
<h3 class=fn><a href="qt.html#Orientation-enum">Orientation</a> <a name="orientation"></a>QDialog::orientation () const
</h3>
Returns the dialog's extension orientation.
<p> <p>See also <a href="#setOrientation">setOrientation</a>().
<h3 class=fn>void <a name="reject"></a>QDialog::reject ()<tt> [virtual protected slot]</tt>
</h3>
Hides the modal dialog and sets the result code to <a href="#DialogCode-enum">Rejected</a>.
<p> <p>See also <a href="#accept">accept</a>() and <a href="#done">done</a>().
<h3 class=fn>int <a name="result"></a>QDialog::result () const
</h3>
<p> Returns the modal dialog's result code, <a href="#DialogCode-enum">Accepted</a> or <a href="#DialogCode-enum">Rejected</a>.
<p> Do not call this function if the dialog was constructed with the <a href="qt.html#WidgetFlags-enum">WDestructiveClose</a> flag.
<h3 class=fn>void <a name="setExtension"></a>QDialog::setExtension ( <a href="qwidget.html">QWidget</a>&nbsp;*&nbsp;extension )
</h3>
Sets the widget, <em>extension</em>, to be the dialog's extension,
deleting any previous extension. The dialog takes ownership of the
extension. Note that if 0 is passed any existing extension will be
deleted.
<p> This function must only be called while the dialog is hidden.
<p> <p>See also <a href="#showExtension">showExtension</a>(), <a href="#setOrientation">setOrientation</a>(), and <a href="#extension">extension</a>().
<h3 class=fn>void <a name="setModal"></a>QDialog::setModal ( bool&nbsp;modal )
</h3><p>Sets whether <a href="#show">show</a>() should pop up the dialog as modal or modeless to <em>modal</em>.
See the <a href="qdialog.html#modal-prop">"modal"</a> property for details.
<h3 class=fn>void <a name="setOrientation"></a>QDialog::setOrientation ( <a href="qt.html#Orientation-enum">Orientation</a>&nbsp;orientation )
</h3>
If <em>orientation</em> is <a href="qt.html#Orientation-enum">Horizontal</a>, the extension will be displayed
to the right of the dialog's main area. If <em>orientation</em> is <a href="qt.html#Orientation-enum">Vertical</a>, the extension will be displayed below the dialog's main
area.
<p> <p>See also <a href="#orientation">orientation</a>() and <a href="#setExtension">setExtension</a>().
<h3 class=fn>void <a name="setResult"></a>QDialog::setResult ( int&nbsp;i )<tt> [protected]</tt>
</h3>
<p> Sets the modal dialog's result code to <em>i</em>.
<h3 class=fn>void <a name="setSizeGripEnabled"></a>QDialog::setSizeGripEnabled ( bool )
</h3><p>Sets whether the size grip is enabled.
See the <a href="qdialog.html#sizeGripEnabled-prop">"sizeGripEnabled"</a> property for details.
<h3 class=fn>void <a name="show"></a>QDialog::show ()<tt> [virtual]</tt>
</h3>
Shows the dialog as a <a href="#modeless">modeless</a> dialog.
Control returns immediately to the calling code.
<p> The dialog will be modal or modeless according to the value
of the <a href="#modal-prop">modal</a> property.
<p> <p>See also <a href="#exec">exec</a>() and <a href="#modal-prop">modal</a>.
<p>Examples: <a href="movies-example.html#x494">movies/main.cpp</a>, <a href="regexptester-example.html#x2511">regexptester/main.cpp</a>, <a href="showimg-example.html#x1317">showimg/showimg.cpp</a>, and <a href="sql.html#x2220">sql/overview/form1/main.cpp</a>.
<p>Reimplemented from <a href="qwidget.html#show">QWidget</a>.
<h3 class=fn>void <a name="showExtension"></a>QDialog::showExtension ( bool&nbsp;showIt )<tt> [protected slot]</tt>
</h3>
If <em>showIt</em> is TRUE, the dialog's extension is shown; otherwise the
extension is hidden.
<p> This slot is usually connected to the <a href="qbutton.html#toggled">QButton::toggled</a>() signal
of a <a href="qpushbutton.html">QPushButton</a>.
<p> A dialog with a visible extension is not resizeable.
<p> <p>See also <a href="#show">show</a>(), <a href="#setExtension">setExtension</a>(), and <a href="#setOrientation">setOrientation</a>().
<hr><h2>Property Documentation</h2>
<h3 class=fn>bool <a name="modal-prop"></a>modal</h3> <p>This property holds whether <a href="#show">show</a>() should pop up the dialog as modal or modeless.
<p>By default, this property is false and show() pops up the dialog as
modeless.
<p> <a href="#exec">exec</a>() ignores the value of this property and always pops up the
dialog as modal.
<p> <p>See also <a href="#show">show</a>() and <a href="#exec">exec</a>().
<p>Set this property's value with <a href="#setModal">setModal</a>() and get this property's value with <a href="#isModal">isModal</a>().
<h3 class=fn>bool <a name="sizeGripEnabled-prop"></a>sizeGripEnabled</h3>
<p>This property holds whether the size grip is enabled.
<p>A <a href="qsizegrip.html">QSizeGrip</a> is placed in the bottom right corner of the dialog when this
property is enabled. By default, the size grip is disabled.
<p>Set this property's value with <a href="#setSizeGripEnabled">setSizeGripEnabled</a>() and get this property's value with <a href="#isSizeGripEnabled">isSizeGripEnabled</a>().
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