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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>QCheckBox Class Reference</h1>

<p>The QCheckBox widget provides a checkbox with a text label.
<a href="#details">More...</a>
<p><tt>#include &lt;<a href="qcheckbox-h.html">qcheckbox.h</a>&gt;</tt>
<p>Inherits <a href="qbutton.html">QButton</a>.
<p><a href="qcheckbox-members.html">List of all member functions.</a>
<h2>Public Members</h2>
<ul>
<li class=fn><a href="#QCheckBox"><b>QCheckBox</b></a> ( QWidget&nbsp;*&nbsp;parent, const&nbsp;char&nbsp;*&nbsp;name = 0 )</li>
<li class=fn><a href="#QCheckBox-2"><b>QCheckBox</b></a> ( const&nbsp;QString&nbsp;&amp;&nbsp;text, QWidget&nbsp;*&nbsp;parent, const&nbsp;char&nbsp;*&nbsp;name = 0 )</li>
<li class=fn>bool <a href="#isChecked"><b>isChecked</b></a> () const</li>
<li class=fn>void <a href="#setNoChange"><b>setNoChange</b></a> ()</li>
<li class=fn>void <a href="#setTristate"><b>setTristate</b></a> ( bool&nbsp;y = TRUE )</li>
<li class=fn>bool <a href="#isTristate"><b>isTristate</b></a> () const</li>
</ul>
<h2>Public Slots</h2>
<ul>
<li class=fn>void <a href="#setChecked"><b>setChecked</b></a> ( bool&nbsp;check )</li>
</ul>
<h2>Important Inherited Members</h2>
<ul>
<li class=fn>QString <a href="#text"><b>text</b></a> () const</li>
<li class=fn>virtual void <a href="#setText"><b>setText</b></a> ( const QString &amp; )</li>
<li class=fn>const QPixmap * <a href="#pixmap"><b>pixmap</b></a> () const</li>
<li class=fn>virtual void <a href="#setPixmap"><b>setPixmap</b></a> ( const QPixmap &amp; )</li>
<li class=fn>QKeySequence <a href="#accel"><b>accel</b></a> () const</li>
<li class=fn>virtual void <a href="#setAccel"><b>setAccel</b></a> ( const QKeySequence &amp; )</li>
<li class=fn>bool <a href="#isToggleButton"><b>isToggleButton</b></a> () const</li>
<li class=fn>virtual void <a href="#setDown"><b>setDown</b></a> ( bool )</li>
<li class=fn>bool <a href="#isDown"><b>isDown</b></a> () const</li>
<li class=fn>bool <a href="#isOn"><b>isOn</b></a> () const</li>
<li class=fn>ToggleState <a href="#state"><b>state</b></a> () const</li>
<li class=fn>bool <a href="#autoRepeat"><b>autoRepeat</b></a> () const</li>
<li class=fn>virtual void <a href="#setAutoRepeat"><b>setAutoRepeat</b></a> ( bool )</li>
<li class=fn>bool <a href="#isExclusiveToggle"><b>isExclusiveToggle</b></a> () const</li>
<li class=fn>QButtonGroup * <a href="#group"><b>group</b></a> () const</li>
<li class=fn>void <a href="#toggle"><b>toggle</b></a> ()</li>
<li class=fn>void <a href="#pressed"><b>pressed</b></a> ()</li>
<li class=fn>void <a href="#released"><b>released</b></a> ()</li>
<li class=fn>void <a href="#clicked"><b>clicked</b></a> ()</li>
<li class=fn>void <a href="#toggled"><b>toggled</b></a> ( bool&nbsp;on )</li>
<li class=fn>void <a href="#stateChanged"><b>stateChanged</b></a> ( int&nbsp;state )</li>
</ul>
<h2>Properties</h2>
<ul>
<li class=fn>bool <a href="#autoMask-prop"><b>autoMask</b></a>&nbsp;- whether the checkbox is automatically masked &nbsp;<em>(read only)</em></li>
<li class=fn>bool <a href="#checked-prop"><b>checked</b></a>&nbsp;- whether the checkbox is checked</li>
<li class=fn>bool <a href="#tristate-prop"><b>tristate</b></a>&nbsp;- whether the checkbox is a tri-state checkbox</li>
</ul>
<hr><a name="details"></a><h2>Detailed Description</h2>


The QCheckBox widget provides a checkbox with a text label.
<p> 

<p> QCheckBox and <a href="qradiobutton.html">QRadioButton</a> are both option buttons. That is, they
can be switched on (checked) or off (unchecked). The classes
differ in how the choices for the user are restricted. Radio
buttons define a "one of many" choice, whereas checkboxes provide
"many of many" choices.
<p> A <a href="qbuttongroup.html">QButtonGroup</a> can be used to group check buttons visually.
<p> Whenever a checkbox is checked or cleared it emits the signal
<a href="qbutton.html#toggled">toggled</a>(). Connect to this signal if you want to trigger an action
each time the checkbox changes state. You can use <a href="#isChecked">isChecked</a>() to
query whether or not a checkbox is checked.
<p> <b>Warning:</b> The toggled() signal can not be trusted for tristate
checkboxes.
<p> In addition to the usual checked and unchecked states, QCheckBox
optionally provides a third state to indicate "no change". This
is useful whenever you need to give the user the option of neither
checking nor unchecking a checkbox. If you need this third state,
enable it with <a href="#setTristate">setTristate</a>() and use <a href="qbutton.html#state">state</a>() to query the current
toggle state. When a tristate checkbox changes state, it emits the
<a href="qbutton.html#stateChanged">stateChanged</a>() signal.
<p> Just like <a href="qpushbutton.html">QPushButton</a>, a checkbox can display text or a pixmap.
The text can be set in the constructor or with <a href="qbutton.html#setText">setText</a>(); the
pixmap is set with <a href="qbutton.html#setPixmap">setPixmap</a>().
<p> 
<p> <img src=qchkbox-m.png> <img src=qchkbox-w.png>
<p> <p>See also <a href="qbutton.html">QButton</a>, <a href="qradiobutton.html">QRadioButton</a>, <a href="guibooks.html#fowler">Fowler: Check Box</a>, and <a href="basic.html">Basic Widgets</a>.

<hr><h2>Member Function Documentation</h2>
<h3 class=fn><a name="QCheckBox"></a>QCheckBox::QCheckBox ( <a href="qwidget.html">QWidget</a>&nbsp;*&nbsp;parent, const&nbsp;char&nbsp;*&nbsp;name = 0 )
</h3>
Constructs a checkbox with no text.
<p> The <em>parent</em> and <em>name</em> arguments are sent to the <a href="qwidget.html">QWidget</a>
constructor.

<h3 class=fn><a name="QCheckBox-2"></a>QCheckBox::QCheckBox ( const&nbsp;<a href="qstring.html">QString</a>&nbsp;&amp;&nbsp;text, <a href="qwidget.html">QWidget</a>&nbsp;*&nbsp;parent, const&nbsp;char&nbsp;*&nbsp;name = 0 )
</h3>
Constructs a checkbox with text <em>text</em>.
<p> The <em>parent</em> and <em>name</em> arguments are sent to the <a href="qwidget.html">QWidget</a>
constructor.

<h3 class=fn><a href="qkeysequence.html">QKeySequence</a> <a name="accel"></a>QButton::accel () const
</h3><p>Returns the accelerator associated with the button.
See the <a href="qbutton.html#accel-prop">"accel"</a> property for details.
<h3 class=fn>bool <a name="autoRepeat"></a>QButton::autoRepeat () const
</h3><p>Returns TRUE if autoRepeat is enabled; otherwise returns FALSE.
See the <a href="qbutton.html#autoRepeat-prop">"autoRepeat"</a> property for details.
<h3 class=fn>void <a name="clicked"></a>QButton::clicked ()<tt> [signal]</tt>
</h3>

<p> This signal is emitted when the button is activated (i.e. first
pressed down and then released when the mouse cursor is inside the
button), when the accelerator key is typed or when <a href="qbutton.html#animateClick">animateClick</a>()
is called. This signal is <em>not</em> emitted if you call <a href="qbutton.html#setDown">setDown</a>().
<p> The <a href="qbuttongroup.html#clicked">QButtonGroup::clicked</a>() signal does the same job, if you want
to connect several buttons to the same slot.
<p> <b>Warning:</b> Don't launch a model dialog in response to this signal
for a button that has <a href="qbutton.html#autoRepeat-prop">autoRepeat</a> turned on.
<p> <p>See also <a href="qbutton.html#pressed">pressed</a>(), <a href="qbutton.html#released">released</a>(), <a href="qbutton.html#toggled">toggled</a>(), <a href="qbutton.html#autoRepeat-prop">autoRepeat</a>, and <a href="qbutton.html#down-prop">down</a>.

<p>Examples: <a href="tutorial2-08.html#x2596">chart/setdataform.cpp</a>, <a href="listbox-example.html#x1426">listbox/listbox.cpp</a>, <a href="clientserver-example.html#x792">network/clientserver/client/client.cpp</a>, <a href="progressbar-example.html#x962">progressbar/progressbar.cpp</a>, <a href="richtext-example.html#x462">richtext/richtext.cpp</a>, <a href="tutorial1-02.html#x2290">t2/main.cpp</a>, and <a href="tutorial1-04.html#x2306">t4/main.cpp</a>.
<h3 class=fn><a href="qbuttongroup.html">QButtonGroup</a>&nbsp;* <a name="group"></a>QButton::group () const
</h3>
Returns the group that this button belongs to.
<p> If the button is not a member of any <a href="qbuttongroup.html">QButtonGroup</a>, this function
returns 0.
<p> <p>See also <a href="qbuttongroup.html">QButtonGroup</a>.

<h3 class=fn>bool <a name="isChecked"></a>QCheckBox::isChecked () const
</h3><p>Returns TRUE if the checkbox is checked; otherwise returns FALSE.
See the <a href="qcheckbox.html#checked-prop">"checked"</a> property for details.
<h3 class=fn>bool <a name="isDown"></a>QButton::isDown () const
</h3><p>Returns TRUE if the button is pressed; otherwise returns FALSE.
See the <a href="qbutton.html#down-prop">"down"</a> property for details.
<h3 class=fn>bool <a name="isExclusiveToggle"></a>QButton::isExclusiveToggle () const
</h3><p>Returns TRUE if the button is an exclusive toggle; otherwise returns FALSE.
See the <a href="qbutton.html#exclusiveToggle-prop">"exclusiveToggle"</a> property for details.
<h3 class=fn>bool <a name="isOn"></a>QButton::isOn () const
</h3><p>Returns TRUE if the button is toggled; otherwise returns FALSE.
See the <a href="qbutton.html#on-prop">"on"</a> property for details.
<h3 class=fn>bool <a name="isToggleButton"></a>QButton::isToggleButton () const
</h3><p>Returns TRUE if the button is a toggle button; otherwise returns FALSE.
See the <a href="qbutton.html#toggleButton-prop">"toggleButton"</a> property for details.
<h3 class=fn>bool <a name="isTristate"></a>QCheckBox::isTristate () const
</h3><p>Returns TRUE if the checkbox is a tri-state checkbox; otherwise returns FALSE.
See the <a href="qcheckbox.html#tristate-prop">"tristate"</a> property for details.
<h3 class=fn>const&nbsp;<a href="qpixmap.html">QPixmap</a>&nbsp;* <a name="pixmap"></a>QButton::pixmap () const
</h3><p>Returns the pixmap shown on the button.
See the <a href="qbutton.html#pixmap-prop">"pixmap"</a> property for details.
<h3 class=fn>void <a name="pressed"></a>QButton::pressed ()<tt> [signal]</tt>
</h3>

<p> This signal is emitted when the button is pressed down.
<p> <p>See also <a href="qbutton.html#released">released</a>() and <a href="qbutton.html#clicked">clicked</a>().

<p>Examples: <a href="httpd-example.html#x724">network/httpd/httpd.cpp</a> and <a href="popup-example.html#x1606">popup/popup.cpp</a>.
<h3 class=fn>void <a name="released"></a>QButton::released ()<tt> [signal]</tt>
</h3>

<p> This signal is emitted when the button is released.
<p> <p>See also <a href="qbutton.html#pressed">pressed</a>(), <a href="qbutton.html#clicked">clicked</a>(), and <a href="qbutton.html#toggled">toggled</a>().

<h3 class=fn>void <a name="setAccel"></a>QButton::setAccel ( const&nbsp;<a href="qkeysequence.html">QKeySequence</a>&nbsp;&amp; )<tt> [virtual]</tt>
</h3><p>Sets the accelerator associated with the button.
See the <a href="qbutton.html#accel-prop">"accel"</a> property for details.
<h3 class=fn>void <a name="setAutoRepeat"></a>QButton::setAutoRepeat ( bool )<tt> [virtual]</tt>
</h3><p>Sets whether autoRepeat is enabled.
See the <a href="qbutton.html#autoRepeat-prop">"autoRepeat"</a> property for details.
<h3 class=fn>void <a name="setChecked"></a>QCheckBox::setChecked ( bool&nbsp;check )<tt> [slot]</tt>
</h3><p>Sets whether the checkbox is checked to <em>check</em>.
See the <a href="qcheckbox.html#checked-prop">"checked"</a> property for details.
<h3 class=fn>void <a name="setDown"></a>QButton::setDown ( bool )<tt> [virtual]</tt>
</h3><p>Sets whether the button is pressed.
See the <a href="qbutton.html#down-prop">"down"</a> property for details.
<h3 class=fn>void <a name="setNoChange"></a>QCheckBox::setNoChange ()
</h3>
Sets the checkbox to the "no change" state.
<p> <p>See also <a href="#tristate-prop">tristate</a>.

<h3 class=fn>void <a name="setPixmap"></a>QButton::setPixmap ( const&nbsp;<a href="qpixmap.html">QPixmap</a>&nbsp;&amp; )<tt> [virtual]</tt>
</h3><p>Sets the pixmap shown on the button.
See the <a href="qbutton.html#pixmap-prop">"pixmap"</a> property for details.
<h3 class=fn>void <a name="setText"></a>QButton::setText ( const&nbsp;<a href="qstring.html">QString</a>&nbsp;&amp; )<tt> [virtual]</tt>
</h3><p>Sets the text shown on the button.
See the <a href="qbutton.html#text-prop">"text"</a> property for details.
<h3 class=fn>void <a name="setTristate"></a>QCheckBox::setTristate ( bool&nbsp;y = TRUE )
</h3><p>Sets whether the checkbox is a tri-state checkbox to <em>y</em>.
See the <a href="qcheckbox.html#tristate-prop">"tristate"</a> property for details.
<h3 class=fn><a href="qbutton.html#ToggleState-enum">ToggleState</a> <a name="state"></a>QButton::state () const
</h3><p>Returns the state of the toggle button.
See the <a href="qbutton.html#toggleState-prop">"toggleState"</a> property for details.
<h3 class=fn>void <a name="stateChanged"></a>QButton::stateChanged ( int&nbsp;state )<tt> [signal]</tt>
</h3>

<p> This signal is emitted whenever a toggle button changes state. <em>state</em> is <a href="qbutton.html#ToggleState-enum">On</a> if the button is on, <a href="qbutton.html#ToggleState-enum">NoChange</a> if it is in the
<a href="#setTristate">"no change" state</a> or <a href="qbutton.html#ToggleState-enum">Off</a>
if the button is off.
<p> This may be the result of a user action, <a href="qbutton.html#toggle">toggle</a>() slot activation,
<a href="qbutton.html#setState">setState</a>(), or because <a href="qbutton.html#setOn">setOn</a>() was called.
<p> <p>See also <a href="qbutton.html#clicked">clicked</a>() and <a href="qbutton.html#ToggleState-enum">QButton::ToggleState</a>.

<h3 class=fn><a href="qstring.html">QString</a> <a name="text"></a>QButton::text () const
</h3><p>Returns the text shown on the button.
See the <a href="qbutton.html#text-prop">"text"</a> property for details.
<h3 class=fn>void <a name="toggle"></a>QButton::toggle ()<tt> [slot]</tt>
</h3>
Toggles the state of a toggle button.
<p> <p>See also <a href="qbutton.html#on-prop">on</a>, <a href="qbutton.html#setOn">setOn</a>(), <a href="qbutton.html#toggled">toggled</a>(), and <a href="qbutton.html#toggleButton-prop">toggleButton</a>.

<h3 class=fn>void <a name="toggled"></a>QButton::toggled ( bool&nbsp;on )<tt> [signal]</tt>
</h3>

<p> This signal is emitted whenever a toggle button changes status. <em>on</em> is TRUE if the button is on, or FALSE if the button is off.
<p> This may be the result of a user action, <a href="qbutton.html#toggle">toggle</a>() slot activation,
or because <a href="qbutton.html#setOn">setOn</a>() was called.
<p> <p>See also <a href="qbutton.html#clicked">clicked</a>().

<p>Example: <a href="listbox-example.html#x1427">listbox/listbox.cpp</a>.
<hr><h2>Property Documentation</h2>
<h3 class=fn><a href="qkeysequence.html">QKeySequence</a> <a name="accel-prop"></a>accel</h3>
<p>This property holds the accelerator associated with the button.
<p>This property is 0 if there is no accelerator set. If you set this
property to 0 then any current accelerator is removed.

<p>Set this property's value with <a href="#setAccel">setAccel</a>() and get this property's value with <a href="#accel">accel</a>().
<h3 class=fn>bool <a name="autoMask-prop"></a>autoMask</h3>
<p>This property holds whether the checkbox is automatically masked.
<p><p><p>See also <a href="qwidget.html#autoMask-prop">QWidget::autoMask</a>.

<h3 class=fn>bool <a name="autoRepeat-prop"></a>autoRepeat</h3>
<p>This property holds whether autoRepeat is enabled.
<p>If autoRepeat is enabled then the <a href="qbutton.html#clicked">clicked</a>() signal is emitted at
regular intervals if the button is down. This property has no
effect on toggle buttons. autoRepeat is off by default.

<p>Set this property's value with <a href="#setAutoRepeat">setAutoRepeat</a>() and get this property's value with <a href="#autoRepeat">autoRepeat</a>().
<h3 class=fn>bool <a name="checked-prop"></a>checked</h3>
<p>This property holds whether the checkbox is checked.
<p>The default is unchecked, i.e. FALSE.

<p>Set this property's value with <a href="#setChecked">setChecked</a>() and get this property's value with <a href="#isChecked">isChecked</a>().
<h3 class=fn><a href="qpixmap.html">QPixmap</a> <a name="pixmap-prop"></a>pixmap</h3>
<p>This property holds the pixmap shown on the button.
<p>If the pixmap is monochrome (i.e. it is a <a href="qbitmap.html">QBitmap</a> or its <a href="qpixmap.html#depth">depth</a> is 1) and it does not have a mask,
this property will set the pixmap to be its own mask. The purpose
of this is to draw transparent bitmaps which are important for
toggle buttons, for example.
<p> <a href="qbutton.html#pixmap">pixmap</a>() returns 0 if no pixmap was set.

<p>Set this property's value with <a href="#setPixmap">setPixmap</a>() and get this property's value with <a href="#pixmap">pixmap</a>().
<h3 class=fn><a href="qstring.html">QString</a> <a name="text-prop"></a>text</h3>
<p>This property holds the text shown on the button.
<p>This property will return a <a href="qstring.html#QString-null">QString::null</a> if the button has no
text. If the text has an ampersand (&amp;) in it, then an
accelerator is automatically created for it using the character
that follows the '&amp;' as the accelerator key. Any previous
accelerator will be overwritten, or cleared if no accelerator is
defined by the text.
<p> There is no default text.

<p>Set this property's value with <a href="#setText">setText</a>() and get this property's value with <a href="#text">text</a>().
<h3 class=fn>bool <a name="tristate-prop"></a>tristate</h3>
<p>This property holds whether the checkbox is a tri-state checkbox.
<p>The default is two-state, i.e. tri-state is FALSE.

<p>Set this property's value with <a href="#setTristate">setTristate</a>() and get this property's value with <a href="#isTristate">isTristate</a>().
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