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diff --git a/doc/html/qsettings.html b/doc/html/qsettings.html new file mode 100644 index 0000000..d8a3dd8 --- /dev/null +++ b/doc/html/qsettings.html @@ -0,0 +1,626 @@ +<!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/src/tools/qsettings.cpp:67 --> +<html> +<head> +<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1"> +<title>QSettings Class</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>QSettings Class Reference</h1> + +<p>The QSettings class provides persistent platform-independent application settings. +<a href="#details">More...</a> +<p><tt>#include <<a href="qsettings-h.html">qsettings.h</a>></tt> +<p><a href="qsettings-members.html">List of all member functions.</a> +<h2>Public Members</h2> +<ul> +<li class=fn>enum <a href="#Format-enum"><b>Format</b></a> { Native = 0, Ini }</li> +<li class=fn>enum <a href="#System-enum"><b>System</b></a> { Unix = 0, Windows, Mac }</li> +<li class=fn>enum <a href="#Scope-enum"><b>Scope</b></a> { User, Global }</li> +<li class=fn><a href="#QSettings"><b>QSettings</b></a> ()</li> +<li class=fn><a href="#QSettings-2"><b>QSettings</b></a> ( Format format )</li> +<li class=fn><a href="#~QSettings"><b>~QSettings</b></a> ()</li> +<li class=fn>bool <a href="#writeEntry"><b>writeEntry</b></a> ( const QString & key, bool value )</li> +<li class=fn>bool <a href="#writeEntry-2"><b>writeEntry</b></a> ( const QString & key, double value )</li> +<li class=fn>bool <a href="#writeEntry-3"><b>writeEntry</b></a> ( const QString & key, int value )</li> +<li class=fn>bool <a href="#writeEntry-5"><b>writeEntry</b></a> ( const QString & key, const QString & value )</li> +<li class=fn>bool <a href="#writeEntry-6"><b>writeEntry</b></a> ( const QString & key, const QStringList & value )</li> +<li class=fn>bool writeEntry ( const QString & key, const QStringList & value, const QChar & separator ) <em>(obsolete)</em></li> +<li class=fn>QStringList <a href="#entryList"><b>entryList</b></a> ( const QString & key ) const</li> +<li class=fn>QStringList <a href="#subkeyList"><b>subkeyList</b></a> ( const QString & key ) const</li> +<li class=fn>QStringList <a href="#readListEntry"><b>readListEntry</b></a> ( const QString & key, bool * ok = 0 ) const</li> +<li class=fn>QStringList readListEntry ( const QString & key, const QChar & separator, bool * ok = 0 ) const <em>(obsolete)</em></li> +<li class=fn>QString <a href="#readEntry"><b>readEntry</b></a> ( const QString & key, const QString & def = QString::null, bool * ok = 0 ) const</li> +<li class=fn>int <a href="#readNumEntry"><b>readNumEntry</b></a> ( const QString & key, int def = 0, bool * ok = 0 ) const</li> +<li class=fn>double <a href="#readDoubleEntry"><b>readDoubleEntry</b></a> ( const QString & key, double def = 0, bool * ok = 0 ) const</li> +<li class=fn>bool <a href="#readBoolEntry"><b>readBoolEntry</b></a> ( const QString & key, bool def = FALSE, bool * ok = 0 ) const</li> +<li class=fn>bool <a href="#removeEntry"><b>removeEntry</b></a> ( const QString & key )</li> +<li class=fn>void <a href="#insertSearchPath"><b>insertSearchPath</b></a> ( System s, const QString & path )</li> +<li class=fn>void <a href="#removeSearchPath"><b>removeSearchPath</b></a> ( System s, const QString & path )</li> +<li class=fn>void <a href="#setPath"><b>setPath</b></a> ( const QString & domain, const QString & product, Scope scope = Global )</li> +<li class=fn>void <a href="#beginGroup"><b>beginGroup</b></a> ( const QString & group )</li> +<li class=fn>void <a href="#endGroup"><b>endGroup</b></a> ()</li> +<li class=fn>void <a href="#resetGroup"><b>resetGroup</b></a> ()</li> +<li class=fn>QString <a href="#group"><b>group</b></a> () const</li> +</ul> +<hr><a name="details"></a><h2>Detailed Description</h2> + + +The QSettings class provides persistent platform-independent application settings. +<p> + + +<p> On Unix systems, QSettings uses text files to store settings. On Windows +systems, QSettings uses the system registry. On Mac OS X, QSettings uses +the Carbon preferences API. +<p> Each setting comprises an identifying key and the data associated with +the key. A key is a unicode string which consists of <em>two</em> or more +subkeys. A subkey is a slash, '/', followed by one or more unicode +characters (excluding slashes, newlines, carriage returns and equals, +'=', signs). The associated data, called the entry or value, may be a +boolean, an integer, a double, a string or a list of strings. Entry +strings may contain any unicode characters. +<p> If you want to save and restore the entire desktop's settings, i.e. +which applications are running, use QSettings to save the settings +for each individual application and <a href="qsessionmanager.html">QSessionManager</a> to save the +desktop's session. +<p> Example settings: +<pre> + /MyCompany/MyApplication/background color + /MyCompany/MyApplication/foreground color + /MyCompany/MyApplication/geometry/x + /MyCompany/MyApplication/geometry/y + /MyCompany/MyApplication/geometry/width + /MyCompany/MyApplication/geometry/height + /MyCompany/MyApplication/recent files/1 + /MyCompany/MyApplication/recent files/2 + /MyCompany/MyApplication/recent files/3 + </pre> + +Each line above is a complete key, made up of subkeys. +<p> A typical usage pattern for reading settings at application +startup: +<pre> + QSettings settings; + settings.<a href="#setPath">setPath</a>( "MyCompany.com", "MyApplication" ); + + <a href="qstring.html">QString</a> bgColor = settings.<a href="#readEntry">readEntry</a>( "/colors/background", "white" ); + int width = settings.<a href="#readNumEntry">readNumEntry</a>( "/geometry/width", 640 ); + // ... + </pre> + +<p> A typical usage pattern for saving settings at application exit or +'save preferences': +<pre> + QSettings settings; + settings.<a href="#setPath">setPath</a>( "MyCompany.com", "MyApplication" ); + + settings.<a href="#writeEntry">writeEntry</a>( "/colors/background", bgColor ); + settings.<a href="#writeEntry">writeEntry</a>( "/geometry/width", width ); + // ... + </pre> + +<p> A key prefix can be prepended to all keys using <a href="#beginGroup">beginGroup</a>(). The +application of the prefix is stopped using <a href="#endGroup">endGroup</a>(). For +example: +<pre> + QSettings settings; + + settings.<a href="#beginGroup">beginGroup</a>( "/MainWindow" ); + settings.<a href="#beginGroup">beginGroup</a>( "/Geometry" ); + int x = settings.<a href="#readEntry">readEntry</a>( "/x" ); + // ... + settings.<a href="#endGroup">endGroup</a>(); + settings.<a href="#beginGroup">beginGroup</a>( "/Toolbars" ); + // ... + settings.<a href="#endGroup">endGroup</a>(); + settings.<a href="#endGroup">endGroup</a>(); + </pre> + +<p> You can get a list of entry-holding keys by calling <a href="#entryList">entryList</a>(), and +a list of key-holding keys using <a href="#subkeyList">subkeyList</a>(). +<p> <pre> + <a href="qstringlist.html">QStringList</a> keys = settings.entryList( "/MyApplication" ); + // keys contains 'background color' and 'foreground color'. + + <a href="qstringlist.html">QStringList</a> keys = settings.entryList( "/MyApplication/recent files" ); + // keys contains '1', '2' and '3'. + + <a href="qstringlist.html">QStringList</a> subkeys = settings.subkeyList( "/MyApplication" ); + // subkeys contains 'geometry' and 'recent files' + + <a href="qstringlist.html">QStringList</a> subkeys = settings.subkeyList( "/MyApplication/recent files" ); + // subkeys is empty. + </pre> + +<p> Since settings for Windows are stored in the registry there are +some size limitations as follows: +<ul> +<li> A subkey may not exceed 255 characters. +<li> An entry's value may not exceed 16,300 characters. +<li> All the values of a key (for example, all the 'recent files' +subkeys values), may not exceed 65,535 characters. +</ul> +<p> These limitations are not enforced on Unix or Mac OS X. +<p> <b>Warning:</b> Creating multiple, simultaneous instances of QSettings writing +to a text file may lead to data loss! This is a known issue which will +be fixed in a future release of Qt. +<p> <h3> Notes for Mac OS X Applications +</h3> +<a name="1"></a><p> The location where settings are stored is not formally defined by +the CFPreferences API. +<p> At the time of writing settings are stored (either on a global or +user basis, preferring locally) into a plist file in <tt>$ROOT/System/Library/Preferences</tt> (in XML format). QSettings will +create an appropriate plist file (<tt>com.<first group name>.plist</tt>) +out of the full path to a key. +<p> For further information on CFPreferences see +<a href="http://developer.apple.com/documentation/CoreFoundation/Conceptual/CFPreferences/index.html">Apple's Specifications</a> +<p> <h3> Notes for Unix Applications +</h3> +<a name="1-1"></a><p> There is no universally accepted place for storing application +settings under Unix. In the examples the settings file will be +searched for in the following directories: +<ol type=1> +<li> <tt>SYSCONF</tt> - the default value is <tt>INSTALL/etc/settings</tt> +<li> <tt>/opt/MyCompany/share/etc</tt> +<li> <tt>/opt/MyCompany/share/MyApplication/etc</tt> +<li> <tt>$HOME/.qt</tt> +</ol> +When reading settings the files are searched in the order shown +above, with later settings overriding earlier settings. Files for +which the user doesn't have read permission are ignored. When saving +settings QSettings works in the order shown above, writing +to the first settings file for which the user has write permission. +(<tt>INSTALL</tt> is the directory where Qt was installed. This can be +modified by using the configure script's -prefix argument ) +<p> If you want to put the settings in a particular place in the +filesystem you could do this: +<pre> + settings.insertSearchPath( QSettings::<a href="#System-enum">Unix</a>, "/opt/MyCompany/share" ); + </pre> + +<p> But in practice you may prefer not to use a search path for Unix. +For example the following code: +<pre> + settings.writeEntry( "/MyApplication/geometry/width", width ); + </pre> + +will end up writing the "geometry/width" setting to the file +<tt>$HOME/.qt/myapplicationrc</tt> (assuming that the application is +being run by an ordinary user, i.e. not by root). +<p> For cross-platform applications you should ensure that the +<a href="#sizelimit">Windows size limitations</a> are not exceeded. +<p> <b>Warning:</b> QSettings doesn't write the settings until it is destroyed so +you should construct the QSettings object on the stack. +<p>See also <a href="io.html">Input/Output and Networking</a> and <a href="misc.html">Miscellaneous Classes</a>. + +<hr><h2>Member Type Documentation</h2> +<h3 class=fn><a name="Format-enum"></a>QSettings::Format</h3> + +<ul> +<li><tt>QSettings::Native</tt> - Store the settings in a platform dependent location +<li><tt>QSettings::Ini</tt> - Store the settings in a text file +</ul> +<h3 class=fn><a name="Scope-enum"></a>QSettings::Scope</h3> + +<ul> +<li><tt>QSettings::Global</tt> - Save settings as global as possible +<li><tt>QSettings::User</tt> - Save settings in user space +</ul> +<h3 class=fn><a name="System-enum"></a>QSettings::System</h3> + +<ul> +<li><tt>QSettings::Mac</tt> - Macintosh execution environments +<li><tt>QSettings::Unix</tt> - Mac OS X, Unix, Linux and Unix-like execution environments +<li><tt>QSettings::Windows</tt> - Windows execution environments +</ul> +<hr><h2>Member Function Documentation</h2> +<h3 class=fn><a name="QSettings"></a>QSettings::QSettings () +</h3> +Creates a settings object. +<p> Be aware that you must call <a href="#setPath">setPath</a>() or <a href="#insertSearchPath">insertSearchPath</a>() before +you can use the QSettings object. + +<h3 class=fn><a name="QSettings-2"></a>QSettings::QSettings ( <a href="qsettings.html#Format-enum">Format</a> format ) +</h3> +Creates a settings object. If <em>format</em> is 'Ini' the settings will +be stored in a text file, using the Unix strategy (see above). If <em>format</em> +is 'Native', the settings will be stored in a platform specific way +(ie. the Windows registry). +<p> Be aware that you must call <a href="#setPath">setPath</a>() or <a href="#insertSearchPath">insertSearchPath</a>() before +you can use the QSettings object. + +<h3 class=fn><a name="~QSettings"></a>QSettings::~QSettings () +</h3> +Destroys the settings object. All modifications made to the settings +will automatically be saved. +<p> +<h3 class=fn>void <a name="beginGroup"></a>QSettings::beginGroup ( const <a href="qstring.html">QString</a> & group ) +</h3> +Appends <em>group</em> to the current key prefix. +<p> <pre> + QSettings settings; + settings.<a href="#beginGroup">beginGroup</a>( "/MainWindow" ); + // read values + settings.<a href="#endGroup">endGroup</a>(); + </pre> + + +<h3 class=fn>void <a name="endGroup"></a>QSettings::endGroup () +</h3> +Undo previous calls to <a href="#beginGroup">beginGroup</a>(). Note that a single beginGroup("a/b/c") is undone +by a single call to <a href="#endGroup">endGroup</a>(). +<p> <pre> + QSettings settings; + settings.<a href="#beginGroup">beginGroup</a>( "/MainWindow/Geometry" ); + // read values + settings.<a href="#endGroup">endGroup</a>(); + </pre> + + +<h3 class=fn><a href="qstringlist.html">QStringList</a> <a name="entryList"></a>QSettings::entryList ( const <a href="qstring.html">QString</a> & key ) const +</h3> +Returns a list of the keys which contain entries under <em>key</em>. Does <em>not</em> return any keys that contain subkeys. +<p> Example settings: +<pre> + /MyCompany/MyApplication/background color + /MyCompany/MyApplication/foreground color + /MyCompany/MyApplication/geometry/x + /MyCompany/MyApplication/geometry/y + /MyCompany/MyApplication/geometry/width + /MyCompany/MyApplication/geometry/height + </pre> + +<pre> + <a href="qstringlist.html">QStringList</a> keys = settings.entryList( "/MyCompany/MyApplication" ); + </pre> + +<p> In the above example, <tt>keys</tt> will contain 'background color' and +'foreground color'. It will not contain 'geometry' because this key +contains subkeys not entries. +<p> To access the geometry values, you could either use <a href="#subkeyList">subkeyList</a>() +to read the keys then read each entry, or simply read each entry +directly by specifying its full key, e.g. +"/MyCompany/MyApplication/geometry/y". +<p> <p>See also <a href="#subkeyList">subkeyList</a>(). + +<h3 class=fn><a href="qstring.html">QString</a> <a name="group"></a>QSettings::group () const +</h3> +Returns the current key prefix, or a null string if there is no key prefix set. +<p> <p>See also <a href="#beginGroup">beginGroup</a>(). + +<h3 class=fn>void <a name="insertSearchPath"></a>QSettings::insertSearchPath ( <a href="qsettings.html#System-enum">System</a> s, const <a href="qstring.html">QString</a> & path ) +</h3> +Inserts <em>path</em> into the settings search path. The semantics of <em>path</em> depends on the system <em>s</em>. It is usually easier and better to +use <a href="#setPath">setPath</a>() instead of this function. +<p> When <em>s</em> is <em>Windows</em> and the execution environment is <em>not</em> +Windows the function does nothing. Similarly when <em>s</em> is <em>Unix</em> and +the execution environment is <em>not</em> Unix the function does nothing. +<p> When <em>s</em> is <em>Windows</em>, and the execution environment is Windows, the +search path list will be used as the first subfolder of the "Software" +folder in the registry. +<p> When reading settings the folders are searched forwards from the +first folder (listed below) to the last, returning the first +settings found, and ignoring any folders for which the user doesn't +have read permission. +<ol type=1> +<li> HKEY_CURRENT_USER/Software/MyCompany/MyApplication +<li> HKEY_LOCAL_MACHINE/Software/MyCompany/MyApplication +<li> HKEY_CURRENT_USER/Software/MyApplication +<li> HKEY_LOCAL_MACHINE/Software/MyApplication +</ol> +<p> <pre> + QSettings settings; + settings.<a href="#insertSearchPath">insertSearchPath</a>( QSettings::<a href="#System-enum">Windows</a>, "/MyCompany" ); + settings.<a href="#writeEntry">writeEntry</a>( "/MyApplication/Tip of the day", TRUE ); + </pre> + +The code above will write the subkey "Tip of the day" into the <em>first</em> of the registry folders listed below that is found and for +which the user has write permission. +<ol type=1> +<li> HKEY_LOCAL_MACHINE/Software/MyCompany/MyApplication +<li> HKEY_CURRENT_USER/Software/MyCompany/MyApplication +<li> HKEY_LOCAL_MACHINE/Software/MyApplication +<li> HKEY_CURRENT_USER/Software/MyApplication +</ol> +If a setting is found in the HKEY_CURRENT_USER space, this setting +is overwritten independently of write permissions in the +HKEY_LOCAL_MACHINE space. +<p> When <em>s</em> is <em>Unix</em>, and the execution environment is Unix, the +search path list will be used when trying to determine a suitable +filename for reading and writing settings files. By default, there are +two entries in the search path: +<p> <ol type=1> +<li> <tt>SYSCONF</tt> - where <tt>SYSCONF</tt> is a directory specified when +configuring Qt; by default it is INSTALL/etc/settings. +<li> <tt>$HOME/.qt/</tt> - where <tt>$HOME</tt> is the user's home directory. +</ol> +<p> All insertions into the search path will go before $HOME/.qt/. +For example: +<pre> + QSettings settings; + settings.<a href="#insertSearchPath">insertSearchPath</a>( QSettings::<a href="#System-enum">Unix</a>, "/opt/MyCompany/share/etc" ); + settings.<a href="#insertSearchPath">insertSearchPath</a>( QSettings::<a href="#System-enum">Unix</a>, "/opt/MyCompany/share/MyApplication/etc" ); + // ... + </pre> + +Will result in a search path of: +<ol type=1> +<li> SYSCONF +<li> /opt/MyCompany/share/etc +<li> /opt/MyCompany/share/MyApplication/etc +<li> $HOME/.qt +</ol> +When reading settings the files are searched in the order shown +above, with later settings overriding earlier settings. Files for +which the user doesn't have read permission are ignored. When saving +settings QSettings works in the order shown above, writing +to the first settings file for which the user has write permission. +<p> Note that paths in the file system are not created by this +function, so they must already exist to be useful. +<p> Settings under Unix are stored in files whose names are based on the +first subkey of the key (not including the search path). The algorithm +for creating names is essentially: lowercase the first subkey, replace +spaces with underscores and add 'rc', e.g. +<tt>/MyCompany/MyApplication/background color</tt> will be stored in +<tt>myapplicationrc</tt> (assuming that <tt>/MyCompany</tt> is part of +the search path). +<p> <p>See also <a href="#removeSearchPath">removeSearchPath</a>(). + +<p> +<p>Example: <a href="canvas-chart-example.html#x2890">chart/chartform.cpp</a>. +<h3 class=fn>bool <a name="readBoolEntry"></a>QSettings::readBoolEntry ( const <a href="qstring.html">QString</a> & key, bool def = FALSE, bool * ok = 0 ) const +</h3> + +<p> Reads the entry specified by <em>key</em>, and returns a bool, or the +default value, <em>def</em>, if the entry couldn't be read. +If <em>ok</em> is non-null, *ok is set to TRUE if the key was read, FALSE +otherwise. +<p> <p>See also <a href="#readEntry">readEntry</a>(), <a href="#readNumEntry">readNumEntry</a>(), <a href="#readDoubleEntry">readDoubleEntry</a>(), <a href="#writeEntry">writeEntry</a>(), and <a href="#removeEntry">removeEntry</a>(). + +<h3 class=fn>double <a name="readDoubleEntry"></a>QSettings::readDoubleEntry ( const <a href="qstring.html">QString</a> & key, double def = 0, bool * ok = 0 ) const +</h3> + +<p> Reads the entry specified by <em>key</em>, and returns a double, or the +default value, <em>def</em>, if the entry couldn't be read. +If <em>ok</em> is non-null, *ok is set to TRUE if the key was read, FALSE +otherwise. +<p> <p>See also <a href="#readEntry">readEntry</a>(), <a href="#readNumEntry">readNumEntry</a>(), <a href="#readBoolEntry">readBoolEntry</a>(), <a href="#writeEntry">writeEntry</a>(), and <a href="#removeEntry">removeEntry</a>(). + +<h3 class=fn><a href="qstring.html">QString</a> <a name="readEntry"></a>QSettings::readEntry ( const <a href="qstring.html">QString</a> & key, const <a href="qstring.html">QString</a> & def = QString::null, bool * ok = 0 ) const +</h3> + +<p> Reads the entry specified by <em>key</em>, and returns a <a href="qstring.html">QString</a>, or the +default value, <em>def</em>, if the entry couldn't be read. +If <em>ok</em> is non-null, *ok is set to TRUE if the key was read, FALSE +otherwise. +<p> <p>See also <a href="#readListEntry">readListEntry</a>(), <a href="#readNumEntry">readNumEntry</a>(), <a href="#readDoubleEntry">readDoubleEntry</a>(), <a href="#readBoolEntry">readBoolEntry</a>(), <a href="#writeEntry">writeEntry</a>(), and <a href="#removeEntry">removeEntry</a>(). + +<h3 class=fn><a href="qstringlist.html">QStringList</a> <a name="readListEntry"></a>QSettings::readListEntry ( const <a href="qstring.html">QString</a> & key, bool * ok = 0 ) const +</h3> + +Reads the entry specified by <em>key</em> as a string. If <em>ok</em> is not +0, <em>*ok</em> is set to TRUE if the key was read, otherwise <em>*ok</em> is +set to FALSE. +<p> Note that if you want to iterate over the list, you should iterate +over a copy, e.g. +<pre> + <a href="qstringlist.html">QStringList</a> list = mySettings.readListEntry( "recentfiles" ); + QStringList::Iterator it = list.<a href="qvaluelist.html#begin">begin</a>(); + while( it != list.<a href="qvaluelist.html#end">end</a>() ) { + myProcessing( *it ); + ++it; + } + </pre> + +<p> <p>See also <a href="#readEntry">readEntry</a>(), <a href="#readDoubleEntry">readDoubleEntry</a>(), <a href="#readBoolEntry">readBoolEntry</a>(), <a href="#writeEntry">writeEntry</a>(), <a href="#removeEntry">removeEntry</a>(), and <a href="qstringlist.html#split">QStringList::split</a>(). + +<h3 class=fn><a href="qstringlist.html">QStringList</a> <a name="readListEntry-4"></a>QSettings::readListEntry ( const <a href="qstring.html">QString</a> & key, const <a href="qchar.html">QChar</a> & separator, bool * ok = 0 ) const +</h3> +This is an overloaded member function, provided for convenience. It behaves essentially like the above function. +<p> <b>This function is obsolete.</b> It is provided to keep old source working. We strongly advise against using it in new code. +<p> Reads the entry specified by <em>key</em> as a string. The <em>separator</em> +is used to create a <a href="qstringlist.html">QStringList</a> by calling <a href="qstringlist.html#split">QStringList::split</a>(<em>separator</em>, entry). If <em>ok</em> is not 0: <em>*ok</em> is set to TRUE +if the key was read, otherwise <em>*ok</em> is set to FALSE. +<p> <b>Warning:</b> As the documentation states, QStringList::split() will +omit empty strings from the list. Because of this, it is +impossible to retrieve identical list data with this function. We +recommend using the <a href="#readListEntry">readListEntry</a>() and <a href="#writeEntry">writeEntry</a>() overloads +that do not take a <em>separator</em> argument. +<p> Note that if you want to iterate over the list, you should iterate +over a copy, e.g. +<pre> + <a href="qstringlist.html">QStringList</a> list = mySettings.readListEntry( "size", " " ); + QStringList::Iterator it = list.<a href="qvaluelist.html#begin">begin</a>(); + while( it != list.<a href="qvaluelist.html#end">end</a>() ) { + myProcessing( *it ); + ++it; + } + </pre> + +<p> <p>See also <a href="#readEntry">readEntry</a>(), <a href="#readDoubleEntry">readDoubleEntry</a>(), <a href="#readBoolEntry">readBoolEntry</a>(), <a href="#writeEntry">writeEntry</a>(), <a href="#removeEntry">removeEntry</a>(), and <a href="qstringlist.html#split">QStringList::split</a>(). + +<h3 class=fn>int <a name="readNumEntry"></a>QSettings::readNumEntry ( const <a href="qstring.html">QString</a> & key, int def = 0, bool * ok = 0 ) const +</h3> + +<p> Reads the entry specified by <em>key</em>, and returns an integer, or the +default value, <em>def</em>, if the entry couldn't be read. +If <em>ok</em> is non-null, *ok is set to TRUE if the key was read, FALSE +otherwise. +<p> <p>See also <a href="#readEntry">readEntry</a>(), <a href="#readDoubleEntry">readDoubleEntry</a>(), <a href="#readBoolEntry">readBoolEntry</a>(), <a href="#writeEntry">writeEntry</a>(), and <a href="#removeEntry">removeEntry</a>(). + +<h3 class=fn>bool <a name="removeEntry"></a>QSettings::removeEntry ( const <a href="qstring.html">QString</a> & key ) +</h3> +Removes the entry specified by <em>key</em>. +<p> Returns true if the entry was successfully removed; otherwise +returns false. Note that removing the last entry in any given +folder, will also remove the folder. +<p> <p>See also <a href="#readEntry">readEntry</a>() and <a href="#writeEntry">writeEntry</a>(). + +<h3 class=fn>void <a name="removeSearchPath"></a>QSettings::removeSearchPath ( <a href="qsettings.html#System-enum">System</a> s, const <a href="qstring.html">QString</a> & path ) +</h3> +Removes all occurrences of <em>path</em> (using exact matching) from the +settings search path for system <em>s</em>. Note that the default search +paths cannot be removed. +<p> <p>See also <a href="#insertSearchPath">insertSearchPath</a>(). + +<h3 class=fn>void <a name="resetGroup"></a>QSettings::resetGroup () +</h3> +Set the current key prefix to the empty string. + +<h3 class=fn>void <a name="setPath"></a>QSettings::setPath ( const <a href="qstring.html">QString</a> & domain, const <a href="qstring.html">QString</a> & product, <a href="qsettings.html#Scope-enum">Scope</a> scope = Global ) +</h3> +Insert platform-dependent paths from platform-independent information. +<p> The <em>domain</em> should be an Internet domain name +controlled by the producer of the software, eg. Trolltech products +use "trolltech.com". +<p> The <em>product</em> should be the official name of the product. +<p> The <em>scope</em> should be +QSettings::User for user-specific settings, or +QSettings::Global for system-wide settings (generally +these will be read-only to many users). +<p> Not all information is relevant on all systems. + +<h3 class=fn><a href="qstringlist.html">QStringList</a> <a name="subkeyList"></a>QSettings::subkeyList ( const <a href="qstring.html">QString</a> & key ) const +</h3> +Returns a list of the keys which contain subkeys under <em>key</em>. Does <em>not</em> return any keys that contain entries. +<p> Example settings: +<pre> + /MyCompany/MyApplication/background color + /MyCompany/MyApplication/foreground color + /MyCompany/MyApplication/geometry/x + /MyCompany/MyApplication/geometry/y + /MyCompany/MyApplication/geometry/width + /MyCompany/MyApplication/geometry/height + /MyCompany/MyApplication/recent files/1 + /MyCompany/MyApplication/recent files/2 + /MyCompany/MyApplication/recent files/3 + </pre> + +<pre> + <a href="qstringlist.html">QStringList</a> keys = settings.subkeyList( "/MyCompany/MyApplication" ); + </pre> + +<p> In the above example, <tt>keys</tt> will contain 'geometry' and +'recent files'. It will not contain 'background color' or +'foreground color' because those keys contain entries not +subkeys. To get a list of keys that contain entries rather than +subkeys use <a href="#entryList">entryList</a>() instead. +<p> <b>Warning:</b> In the above example, if QSettings is writing to an Ini file, +then a call to +<pre> subkeyList("/MyCompany") </pre> + +will return an empty list. This happens because a key like +<pre> /MyCompany/MyApplication/background color </pre> + +is written to the file <em>"mycompanyrc"</em>, under the section <em>[MyApplication]</em>. +This call is therefore a request to list the sections in an ini file, which +is not supported in this version of QSettings. This is a known issue which +will be fixed in Qt-4. +<p> <p>See also <a href="#entryList">entryList</a>(). + +<h3 class=fn>bool <a name="writeEntry"></a>QSettings::writeEntry ( const <a href="qstring.html">QString</a> & key, bool value ) +</h3> +Writes the boolean entry <em>value</em> into key <em>key</em>. The <em>key</em> is +created if it doesn't exist. Any previous value is overwritten by <em>value</em>. +<p> If an error occurs the settings are left unchanged and FALSE is +returned; otherwise TRUE is returned. +<p> <b>Warning:</b> On certain platforms, keys are required to contain at least +two components (e.g., "/foo/bar"). This limitation does not apply to +Qt 4. +<p> <p>See also <a href="#readListEntry">readListEntry</a>(), <a href="#readNumEntry">readNumEntry</a>(), <a href="#readDoubleEntry">readDoubleEntry</a>(), <a href="#readBoolEntry">readBoolEntry</a>(), and <a href="#removeEntry">removeEntry</a>(). + +<p>Example: <a href="canvas-chart-example.html#x2891">chart/chartform.cpp</a>. +<h3 class=fn>bool <a name="writeEntry-2"></a>QSettings::writeEntry ( const <a href="qstring.html">QString</a> & key, double value ) +</h3> +This is an overloaded member function, provided for convenience. It behaves essentially like the above function. +<p> Writes the double entry <em>value</em> into key <em>key</em>. The <em>key</em> is +created if it doesn't exist. Any previous value is overwritten by <em>value</em>. +<p> If an error occurs the settings are left unchanged and FALSE is +returned; otherwise TRUE is returned. +<p> <p>See also <a href="#readListEntry">readListEntry</a>(), <a href="#readNumEntry">readNumEntry</a>(), <a href="#readDoubleEntry">readDoubleEntry</a>(), <a href="#readBoolEntry">readBoolEntry</a>(), and <a href="#removeEntry">removeEntry</a>(). + +<h3 class=fn>bool <a name="writeEntry-3"></a>QSettings::writeEntry ( const <a href="qstring.html">QString</a> & key, int value ) +</h3> +This is an overloaded member function, provided for convenience. It behaves essentially like the above function. +<p> Writes the integer entry <em>value</em> into key <em>key</em>. The <em>key</em> is +created if it doesn't exist. Any previous value is overwritten by <em>value</em>. +<p> If an error occurs the settings are left unchanged and FALSE is +returned; otherwise TRUE is returned. +<p> <p>See also <a href="#readListEntry">readListEntry</a>(), <a href="#readNumEntry">readNumEntry</a>(), <a href="#readDoubleEntry">readDoubleEntry</a>(), <a href="#readBoolEntry">readBoolEntry</a>(), and <a href="#removeEntry">removeEntry</a>(). + +<h3 class=fn>bool <a name="writeEntry-5"></a>QSettings::writeEntry ( const <a href="qstring.html">QString</a> & key, const <a href="qstring.html">QString</a> & value ) +</h3> +This is an overloaded member function, provided for convenience. It behaves essentially like the above function. +<p> Writes the string entry <em>value</em> into key <em>key</em>. The <em>key</em> is +created if it doesn't exist. Any previous value is overwritten by <em>value</em>. If <em>value</em> is an empty string or a null string the key's +value will be an empty string. +<p> If an error occurs the settings are left unchanged and FALSE is +returned; otherwise TRUE is returned. +<p> <p>See also <a href="#readListEntry">readListEntry</a>(), <a href="#readNumEntry">readNumEntry</a>(), <a href="#readDoubleEntry">readDoubleEntry</a>(), <a href="#readBoolEntry">readBoolEntry</a>(), and <a href="#removeEntry">removeEntry</a>(). + +<h3 class=fn>bool <a name="writeEntry-6"></a>QSettings::writeEntry ( const <a href="qstring.html">QString</a> & key, const <a href="qstringlist.html">QStringList</a> & value ) +</h3> +This is an overloaded member function, provided for convenience. It behaves essentially like the above function. +<p> Writes the string list entry <em>value</em> into key <em>key</em>. The <em>key</em> +is created if it doesn't exist. Any previous value is overwritten +by <em>value</em>. +<p> If an error occurs the settings are left unchanged and FALSE is +returned; otherwise returns TRUE. +<p> <p>See also <a href="#readListEntry">readListEntry</a>(), <a href="#readNumEntry">readNumEntry</a>(), <a href="#readDoubleEntry">readDoubleEntry</a>(), <a href="#readBoolEntry">readBoolEntry</a>(), and <a href="#removeEntry">removeEntry</a>(). + +<h3 class=fn>bool <a name="writeEntry-7"></a>QSettings::writeEntry ( const <a href="qstring.html">QString</a> & key, const <a href="qstringlist.html">QStringList</a> & value, const <a href="qchar.html">QChar</a> & separator ) +</h3> +This is an overloaded member function, provided for convenience. It behaves essentially like the above function. +<p> <b>This function is obsolete.</b> It is provided to keep old source working. We strongly advise against using it in new code. +<p> Writes the string list entry <em>value</em> into key <em>key</em>. The <em>key</em> +is created if it doesn't exist. Any previous value is overwritten +by <em>value</em>. The list is stored as a sequence of strings separated +by <em>separator</em> (using <a href="qstringlist.html#join">QStringList::join</a>()), so none of the +strings in the list should contain the separator. If the list is +empty or null the key's value will be an empty string. +<p> <b>Warning:</b> The list should not contain empty or null strings, as +<a href="#readListEntry">readListEntry</a>() will use <a href="qstringlist.html#split">QStringList::split</a>() to recreate the +list. As the documentation states, QStringList::split() will omit +empty strings from the list. Because of this, it is impossible to +retrieve identical list data that is stored with this function. +We recommend using the <a href="#writeEntry">writeEntry</a>() and readListEntry() overloads +that do not take a <em>separator</em> argument. +<p> If an error occurs the settings are left unchanged and FALSE is +returned; otherwise returns TRUE. +<p> <p>See also <a href="#readListEntry">readListEntry</a>(), <a href="#readNumEntry">readNumEntry</a>(), <a href="#readDoubleEntry">readDoubleEntry</a>(), <a href="#readBoolEntry">readBoolEntry</a>(), <a href="#removeEntry">removeEntry</a>(), and <a href="qstringlist.html#join">QStringList::join</a>(). + +<!-- eof --> +<hr><p> +This file is part of the <a href="index.html">Qt toolkit</a>. +Copyright © 1995-2007 +<a href="http://www.trolltech.com/">Trolltech</a>. All Rights Reserved.<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> |