QSqlForm Class Reference
[sql module]

Detailed Description

Typical use of a QSqlForm consists of the following steps:

• Create the widgets you want to appear in the form.
• Create a cursor and navigate to the record to be edited.
• Create the QSqlForm.
• Set the form's record buffer to the cursor's update buffer.
• Insert each widget and the field it is to edit into the form.
• Use readFields() to update the editor widgets with values from the database's fields.
• Display the form and let the user edit values etc.
• Use writeFields() to update the database's field values with the values in the editor widgets.

Note that a QSqlForm does not access the database directly, but most often via QSqlFields which are part of a QSqlCursor. A QSqlCursor::insert(), QSqlCursor::update() or QSqlCursor::del() call is needed to actually write values to the database.

Some sample code to initialize a form successfully:

    QLineEdit  myEditor( this );
    QSqlForm   myForm( this );
    QSqlCursor myCursor( "mytable" );

    // Execute a query to make the cursor valid
    myCursor.select();
    // Move the cursor to a valid record (the first record)
    myCursor.next();
    // Set the form's record pointer to the cursor's edit buffer (which
    // contains the current record's values)
    myForm.setRecord( myCursor.primeUpdate() );

    // Insert a field into the form that uses myEditor to edit the
    // field 'somefield' in 'mytable'
    myForm.insert( &myEditor, "somefield" );

    // Update myEditor with the value from the mapped database field
    myForm.readFields();
    ...
    // Let the user edit the form
    ...
    // Update the database
    myForm.writeFields();  // Update the cursor's edit buffer from the form
    myCursor.update();  // Update the database from the cursor's buffer
    

If you want to use custom editors for displaying and editing data fields, you must install a custom QSqlPropertyMap. The form uses this object to get or set the value of a widget.

Note that Qt Designer provides a visual means of creating data-aware forms.

See also installPropertyMap(), QSqlPropertyMap, and Database Classes.

Member Function Documentation

QSqlForm::QSqlForm ( QObject * parent = 0, const char * name = 0 )

QSqlForm::~QSqlForm ()

void QSqlForm::clear () [virtual slot]

void QSqlForm::clearValues ( bool nullify = FALSE ) [virtual slot]

uint QSqlForm::count () const

QWidget * QSqlForm::fieldToWidget ( QSqlField * field ) const

void QSqlForm::insert ( QWidget * widget, const QString & field ) [virtual]

See also setRecord().

Examples: sql/overview/form1/main.cpp and sql/overview/form2/main.cpp.

void QSqlForm::insert ( QWidget * widget, QSqlField * field ) [virtual protected]

Inserts a widget, and the field it is to be mapped to, into the form.

void QSqlForm::installPropertyMap ( QSqlPropertyMap * pmap )

QSqlForm takes ownership of pmap, so pmap is deleted when QSqlForm goes out of scope.

See also QDataTable::installEditorFactory().

Example: sql/overview/custom1/main.cpp.

void QSqlForm::readField ( QWidget * widget ) [virtual slot]

void QSqlForm::readFields () [virtual slot]

Examples: sql/overview/form1/main.cpp and sql/overview/form2/main.cpp.

void QSqlForm::remove ( QWidget * widget ) [virtual protected]

void QSqlForm::remove ( const QString & field ) [virtual]

Removes field from the form.

void QSqlForm::setRecord ( QSqlRecord * buf ) [virtual]

See also readFields() and writeFields().

Examples: sql/overview/custom1/main.cpp, sql/overview/form1/main.cpp, and sql/overview/form2/main.cpp.

QWidget * QSqlForm::widget ( uint i ) const

QSqlField * QSqlForm::widgetToField ( QWidget * widget ) const

void QSqlForm::writeField ( QWidget * widget ) [virtual slot]

void QSqlForm::writeFields () [virtual slot]

Example: sql/overview/form2/main.cpp.

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