QStyleOption Class Reference

Detailed Description

Some QStyle functions take an optional argument specifying extra information that is required for a paritical primitive or control. So that the QStyle class can be extended, QStyleOption is used to provide a variable-argument for these options.

The QStyleOption class has constructors for each type of optional argument, and this set of constructors may be extended in future Qt releases. There are also corresponding access functions that return the optional arguments: these too may be extended.

For each constructor, you should refer to the documentation of the QStyle functions to see the meaning of the arguments.

When calling QStyle functions from your own widgets, you must only pass either the default QStyleOption or the argument that QStyle is documented to accept. For example, if the function expects QStyleOption(QMenuItem *, int), passing QStyleOption(QMenuItem *) leaves the optional integer argument uninitialized.

When subclassing QStyle, you must similarly only expect the default or documented arguments. The other arguments will have uninitialized values.

If you make your own QStyle subclasses and your own widgets, you can make a subclass of QStyleOption to pass additional arguments to your QStyle subclass. You will need to cast the "const QStyleOption&" argument to your subclass, so be sure your style has been called from your widget.

See also Widget Appearance and Style.

Member Type Documentation

QStyleOption::StyleOptionDefault

This enum value can be passed as the optional argument to any QStyle function.

• QStyleOption::Default

Member Function Documentation

QStyleOption::QStyleOption ( StyleOptionDefault = Default )

The default option. This can always be passed as the optional argument to QStyle functions.

QStyleOption::QStyleOption ( int in1, int in2 )

Pass two integers, in1 and in2. For example, linewidth and midlinewidth.

QStyleOption::QStyleOption ( int in1, int in2, int in3, int in4 )

Pass four integers, in1, in2, in3 and in4.

QStyleOption::QStyleOption ( QMenuItem * m )

Pass a menu item, m.

QStyleOption::QStyleOption ( QMenuItem * m, int in1 )

Pass a menu item and an integer, m and in1.

QStyleOption::QStyleOption ( QMenuItem * m, int in1, int in2 )

Pass a menu item and two integers, m, in1 and in2.

QStyleOption::QStyleOption ( const QColor & c )

Pass a color, c.

QStyleOption::QStyleOption ( QTab * t )

Pass a QTab, t.

QStyleOption::QStyleOption ( QListViewItem * i )

Pass a QListViewItem, i.

QStyleOption::QStyleOption ( Qt::ArrowType a )

Pass an Qt::ArrowType, a.

Qt::ArrowType QStyleOption::arrowType () const

Returns an arrow type if the appropriate constructor was called; otherwise the return value is undefined.

const QColor & QStyleOption::color () const

Returns a color if the appropriate constructor was called; otherwise the return value is undefined.

int QStyleOption::frameShadow () const

Returns a QFrame::Shadow value if the appropriate constructor was called; otherwise the return value is undefined.

int QStyleOption::frameShape () const

Returns a QFrame::Shape value if the appropriate constructor was called; otherwise the return value is undefined.

bool QStyleOption::isDefault () const

Returns TRUE if the option was constructed with the default constructor; otherwise returns FALSE.

int QStyleOption::lineWidth () const

Returns the line width if the appropriate constructor was called; otherwise the return value is undefined.

QListViewItem * QStyleOption::listViewItem () const

Returns a QListView item if the appropriate constructor was called; otherwise the return value is undefined.

int QStyleOption::maxIconWidth () const

Returns the maximum width of the menu item check area if the appropriate constructor was called; otherwise the return value is undefined.

QMenuItem * QStyleOption::menuItem () const

Returns a menu item if the appropriate constructor was called; otherwise the return value is undefined.

int QStyleOption::midLineWidth () const

Returns the mid-line width if the appropriate constructor was called; otherwise the return value is undefined.

QTab * QStyleOption::tab () const

Returns a QTabBar tab if the appropriate constructor was called; otherwise the return value is undefined.

int QStyleOption::tabWidth () const

Returns the tab indent width if the appropriate constructor was called; otherwise the return value is undefined.

This file is part of the Qt toolkit. Copyright © 1995-2002 Trolltech. All Rights Reserved.