You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
tqt3/doc/html/tqsqlform.html

238 lines
13 KiB

<!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/sql/tqsqlform.cpp:61 -->
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>TQSqlForm 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&nbsp;Classes</font></a>
| <a href="mainclasses.html">
<font color="#004faf">Main&nbsp;Classes</font></a>
| <a href="annotated.html">
<font color="#004faf">Annotated</font></a>
| <a href="groups.html">
<font color="#004faf">Grouped&nbsp;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>TQSqlForm Class Reference<br><small>[<a href="sql.html">sql module</a>]</small></h1>
<p>The TQSqlForm class creates and manages data entry forms
tied to SQL databases.
<a href="#details">More...</a>
<p><tt>#include &lt;<a href="tqsqlform-h.html">tqsqlform.h</a>&gt;</tt>
<p>Inherits <a href="tqobject.html">TQObject</a>.
<p><a href="tqsqlform-members.html">List of all member functions.</a>
<h2>Public Members</h2>
<ul>
<li class=fn><a href="#TQSqlForm"><b>TQSqlForm</b></a> ( TQObject&nbsp;*&nbsp;parent = 0, const&nbsp;char&nbsp;*&nbsp;name = 0 )</li>
<li class=fn><a href="#~TQSqlForm"><b>~TQSqlForm</b></a> ()</li>
<li class=fn>virtual void <a href="#insert"><b>insert</b></a> ( TQWidget&nbsp;*&nbsp;widget, const&nbsp;TQString&nbsp;&amp;&nbsp;field )</li>
<li class=fn>virtual void <a href="#remove-2"><b>remove</b></a> ( const&nbsp;TQString&nbsp;&amp;&nbsp;field )</li>
<li class=fn>uint <a href="#count"><b>count</b></a> () const</li>
<li class=fn>TQWidget * <a href="#widget"><b>widget</b></a> ( uint&nbsp;i ) const</li>
<li class=fn>TQSqlField * <a href="#widgetToField"><b>widgetToField</b></a> ( TQWidget&nbsp;*&nbsp;widget ) const</li>
<li class=fn>TQWidget * <a href="#fieldToWidget"><b>fieldToWidget</b></a> ( TQSqlField&nbsp;*&nbsp;field ) const</li>
<li class=fn>void <a href="#installPropertyMap"><b>installPropertyMap</b></a> ( TQSqlPropertyMap&nbsp;*&nbsp;pmap )</li>
<li class=fn>virtual void <a href="#setRecord"><b>setRecord</b></a> ( TQSqlRecord&nbsp;*&nbsp;buf )</li>
</ul>
<h2>Public Slots</h2>
<ul>
<li class=fn>virtual void <a href="#readField"><b>readField</b></a> ( TQWidget&nbsp;*&nbsp;widget )</li>
<li class=fn>virtual void <a href="#writeField"><b>writeField</b></a> ( TQWidget&nbsp;*&nbsp;widget )</li>
<li class=fn>virtual void <a href="#readFields"><b>readFields</b></a> ()</li>
<li class=fn>virtual void <a href="#writeFields"><b>writeFields</b></a> ()</li>
<li class=fn>virtual void <a href="#clear"><b>clear</b></a> ()</li>
<li class=fn>virtual void <a href="#clearValues"><b>clearValues</b></a> ( bool&nbsp;nullify = FALSE )</li>
</ul>
<h2>Protected Members</h2>
<ul>
<li class=fn>virtual void <a href="#insert-2"><b>insert</b></a> ( TQWidget&nbsp;*&nbsp;widget, TQSqlField&nbsp;*&nbsp;field )</li>
<li class=fn>virtual void <a href="#remove"><b>remove</b></a> ( TQWidget&nbsp;*&nbsp;widget )</li>
</ul>
<hr><a name="details"></a><h2>Detailed Description</h2>
The TQSqlForm class creates and manages data entry forms
tied to SQL databases.
<p>
<p> Typical use of a TQSqlForm consists of the following steps:
<ul>
<li> Create the widgets you want to appear in the form.
<li> Create a cursor and navigate to the record to be edited.
<li> Create the TQSqlForm.
<li> Set the form's record buffer to the cursor's update buffer.
<li> Insert each widget and the field it is to edit into the form.
<li> Use <a href="#readFields">readFields</a>() to update the editor widgets with values from
the database's fields.
<li> Display the form and let the user edit values etc.
<li> Use <a href="#writeFields">writeFields</a>() to update the database's field values with
the values in the editor widgets.
</ul>
<p> Note that a TQSqlForm does not access the database directly, but
most often via TQSqlFields which are part of a <a href="tqsqlcursor.html">TQSqlCursor</a>. A
<a href="tqsqlcursor.html#insert">TQSqlCursor::insert</a>(), <a href="tqsqlcursor.html#update">TQSqlCursor::update</a>() or <a href="tqsqlcursor.html#del">TQSqlCursor::del</a>()
call is needed to actually write values to the database.
<p> Some sample code to initialize a form successfully:
<p> <pre>
<a href="ntqlineedit.html">TQLineEdit</a> myEditor( this );
TQSqlForm myForm( this );
<a href="tqsqlcursor.html">TQSqlCursor</a> myCursor( "mytable" );
// Execute a query to make the cursor valid
myCursor.<a href="tqsqlcursor.html#select">select</a>();
// Move the cursor to a valid record (the first record)
myCursor.<a href="tqsqlquery.html#next">next</a>();
// Set the form's record pointer to the cursor's edit buffer (which
// contains the current record's values)
myForm.<a href="#setRecord">setRecord</a>( myCursor.<a href="tqsqlcursor.html#primeUpdate">primeUpdate</a>() );
// Insert a field into the form that uses myEditor to edit the
// field 'somefield' in 'mytable'
myForm.<a href="#insert">insert</a>( &amp;myEditor, "somefield" );
// Update myEditor with the value from the mapped database field
myForm.<a href="#readFields">readFields</a>();
...
// Let the user edit the form
...
// Update the database
myForm.<a href="#writeFields">writeFields</a>(); // Update the cursor's edit buffer from the form
myCursor.<a href="tqsqlcursor.html#update">update</a>(); // Update the database from the cursor's buffer
</pre>
<p> If you want to use custom editors for displaying and editing data
fields, you must install a custom <a href="tqsqlpropertymap.html">TQSqlPropertyMap</a>. The form
uses this object to get or set the value of a widget.
<p> Note that <a href="designer-manual.html">TQt Designer</a> provides
a visual means of creating data-aware forms.
<p> <p>See also <a href="#installPropertyMap">installPropertyMap</a>(), <a href="tqsqlpropertymap.html">TQSqlPropertyMap</a>, and <a href="database.html">Database Classes</a>.
<hr><h2>Member Function Documentation</h2>
<h3 class=fn><a name="TQSqlForm"></a>TQSqlForm::TQSqlForm ( <a href="tqobject.html">TQObject</a>&nbsp;*&nbsp;parent = 0, const&nbsp;char&nbsp;*&nbsp;name = 0 )
</h3>
Constructs a TQSqlForm with parent <em>parent</em> and called <em>name</em>.
<h3 class=fn><a name="~TQSqlForm"></a>TQSqlForm::~TQSqlForm ()
</h3>
Destroys the object and frees any allocated resources.
<h3 class=fn>void <a name="clear"></a>TQSqlForm::clear ()<tt> [virtual slot]</tt>
</h3>
Removes every widget, and the fields they're mapped to, from the form.
<h3 class=fn>void <a name="clearValues"></a>TQSqlForm::clearValues ( bool&nbsp;nullify = FALSE )<tt> [virtual slot]</tt>
</h3>
Clears the values in all the widgets, and the fields they are
mapped to, in the form. If <em>nullify</em> is TRUE (the default is
FALSE), each field is also set to NULL.
<h3 class=fn>uint <a name="count"></a>TQSqlForm::count () const
</h3>
Returns the number of widgets in the form.
<h3 class=fn><a href="ntqwidget.html">TQWidget</a>&nbsp;* <a name="fieldToWidget"></a>TQSqlForm::fieldToWidget ( <a href="tqsqlfield.html">TQSqlField</a>&nbsp;*&nbsp;field ) const
</h3>
Returns the widget that field <em>field</em> is mapped to.
<h3 class=fn>void <a name="insert"></a>TQSqlForm::insert ( <a href="ntqwidget.html">TQWidget</a>&nbsp;*&nbsp;widget, const&nbsp;<a href="ntqstring.html">TQString</a>&nbsp;&amp;&nbsp;field )<tt> [virtual]</tt>
</h3>
Inserts a <em>widget</em>, and the name of the <em>field</em> it is to be
mapped to, into the form. To actually associate inserted widgets
with an edit buffer, use <a href="#setRecord">setRecord</a>().
<p> <p>See also <a href="#setRecord">setRecord</a>().
<p>Examples: <a href="sql.html#x2225">sql/overview/form1/main.cpp</a> and <a href="sql.html#x2231">sql/overview/form2/main.cpp</a>.
<h3 class=fn>void <a name="insert-2"></a>TQSqlForm::insert ( <a href="ntqwidget.html">TQWidget</a>&nbsp;*&nbsp;widget, <a href="tqsqlfield.html">TQSqlField</a>&nbsp;*&nbsp;field )<tt> [virtual protected]</tt>
</h3>
This is an overloaded member function, provided for convenience. It behaves essentially like the above function.
<p> Inserts a <em>widget</em>, and the <em>field</em> it is to be mapped to, into
the form.
<h3 class=fn>void <a name="installPropertyMap"></a>TQSqlForm::installPropertyMap ( <a href="tqsqlpropertymap.html">TQSqlPropertyMap</a>&nbsp;*&nbsp;pmap )
</h3>
Installs a custom <a href="tqsqlpropertymap.html">TQSqlPropertyMap</a>. This is useful if you plan to
create your own custom editor widgets.
<p> TQSqlForm takes ownership of <em>pmap</em>, so <em>pmap</em> is deleted when
TQSqlForm goes out of scope.
<p> <p>See also <a href="tqdatatable.html#installEditorFactory">TQDataTable::installEditorFactory</a>().
<p>Example: <a href="sql.html#x2237">sql/overview/custom1/main.cpp</a>.
<h3 class=fn>void <a name="readField"></a>TQSqlForm::readField ( <a href="ntqwidget.html">TQWidget</a>&nbsp;*&nbsp;widget )<tt> [virtual slot]</tt>
</h3>
Updates the widget <em>widget</em> with the value from the SQL field it
is mapped to. Nothing happens if no SQL field is mapped to the <em>widget</em>.
<h3 class=fn>void <a name="readFields"></a>TQSqlForm::readFields ()<tt> [virtual slot]</tt>
</h3>
Updates the widgets in the form with current values from the SQL
fields they are mapped to.
<p>Examples: <a href="sql.html#x2226">sql/overview/form1/main.cpp</a> and <a href="sql.html#x2232">sql/overview/form2/main.cpp</a>.
<h3 class=fn>void <a name="remove"></a>TQSqlForm::remove ( <a href="ntqwidget.html">TQWidget</a>&nbsp;*&nbsp;widget )<tt> [virtual protected]</tt>
</h3>
Removes a <em>widget</em>, and hence the field it's mapped to, from the
form.
<h3 class=fn>void <a name="remove-2"></a>TQSqlForm::remove ( const&nbsp;<a href="ntqstring.html">TQString</a>&nbsp;&amp;&nbsp;field )<tt> [virtual]</tt>
</h3>
This is an overloaded member function, provided for convenience. It behaves essentially like the above function.
<p> Removes <em>field</em> from the form.
<h3 class=fn>void <a name="setRecord"></a>TQSqlForm::setRecord ( <a href="tqsqlrecord.html">TQSqlRecord</a>&nbsp;*&nbsp;buf )<tt> [virtual]</tt>
</h3>
Sets <em>buf</em> as the record buffer for the form. To force the
display of the data from <em>buf</em>, use <a href="#readFields">readFields</a>().
<p> <p>See also <a href="#readFields">readFields</a>() and <a href="#writeFields">writeFields</a>().
<p>Examples: <a href="sql.html#x2238">sql/overview/custom1/main.cpp</a>, <a href="sql.html#x2227">sql/overview/form1/main.cpp</a>, and <a href="sql.html#x2233">sql/overview/form2/main.cpp</a>.
<h3 class=fn><a href="ntqwidget.html">TQWidget</a>&nbsp;* <a name="widget"></a>TQSqlForm::widget ( uint&nbsp;i ) const
</h3>
Returns the <em>i</em>-th widget in the form. Useful for traversing
the widgets in the form.
<h3 class=fn><a href="tqsqlfield.html">TQSqlField</a>&nbsp;* <a name="widgetToField"></a>TQSqlForm::widgetToField ( <a href="ntqwidget.html">TQWidget</a>&nbsp;*&nbsp;widget ) const
</h3>
Returns the SQL field that widget <em>widget</em> is mapped to.
<h3 class=fn>void <a name="writeField"></a>TQSqlForm::writeField ( <a href="ntqwidget.html">TQWidget</a>&nbsp;*&nbsp;widget )<tt> [virtual slot]</tt>
</h3>
Updates the SQL field with the value from the <em>widget</em> it is
mapped to. Nothing happens if no SQL field is mapped to the <em>widget</em>.
<h3 class=fn>void <a name="writeFields"></a>TQSqlForm::writeFields ()<tt> [virtual slot]</tt>
</h3>
Updates the SQL fields with values from the widgets they are
mapped to. To actually update the database with the contents of
the record buffer, use <a href="tqsqlcursor.html#insert">TQSqlCursor::insert</a>(), <a href="tqsqlcursor.html#update">TQSqlCursor::update</a>()
or <a href="tqsqlcursor.html#del">TQSqlCursor::del</a>() as appropriate.
<p>Example: <a href="sql.html#x2234">sql/overview/form2/main.cpp</a>.
<!-- eof -->
<hr><p>
This file is part of the <a href="index.html">TQt toolkit</a>.
Copyright &copy; 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 &copy; 2007
<a href="troll.html">Trolltech</a><td align=center><a href="trademarks.html">Trademarks</a>
<td align=right><div align=right>TQt 3.3.8</div>
</table></div></address></body>
</html>