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diff --git a/doc/man/man3/qlayoutitem.3qt b/doc/man/man3/qlayoutitem.3qt new file mode 100644 index 000000000..850704716 --- /dev/null +++ b/doc/man/man3/qlayoutitem.3qt @@ -0,0 +1,226 @@ +'\" t +.TH QLayoutItem 3qt "2 February 2007" "Trolltech AS" \" -*- nroff -*- +.\" Copyright 1992-2007 Trolltech ASA. All rights reserved. See the +.\" license file included in the distribution for a complete license +.\" statement. +.\" +.ad l +.nh +.SH NAME +QLayoutItem \- Abstract item that a QLayout manipulates +.SH SYNOPSIS +\fC#include <qlayout.h>\fR +.PP +Inherited by QLayout, QSpacerItem, and QWidgetItem. +.PP +.SS "Public Members" +.in +1c +.ti -1c +.BI "\fBQLayoutItem\fR ( int alignment = 0 )" +.br +.ti -1c +.BI "virtual \fB~QLayoutItem\fR ()" +.br +.ti -1c +.BI "virtual QSize \fBsizeHint\fR () const = 0" +.br +.ti -1c +.BI "virtual QSize \fBminimumSize\fR () const = 0" +.br +.ti -1c +.BI "virtual QSize \fBmaximumSize\fR () const = 0" +.br +.ti -1c +.BI "virtual QSizePolicy::ExpandData \fBexpanding\fR () const = 0" +.br +.ti -1c +.BI "virtual void \fBsetGeometry\fR ( const QRect & r ) = 0" +.br +.ti -1c +.BI "virtual QRect \fBgeometry\fR () const = 0" +.br +.ti -1c +.BI "virtual bool \fBisEmpty\fR () const = 0" +.br +.ti -1c +.BI "virtual bool \fBhasHeightForWidth\fR () const" +.br +.ti -1c +.BI "virtual int \fBheightForWidth\fR ( int w ) const" +.br +.ti -1c +.BI "virtual void \fBinvalidate\fR ()" +.br +.ti -1c +.BI "virtual QWidget * \fBwidget\fR ()" +.br +.ti -1c +.BI "virtual QLayoutIterator \fBiterator\fR ()" +.br +.ti -1c +.BI "virtual QLayout * \fBlayout\fR ()" +.br +.ti -1c +.BI "virtual QSpacerItem * \fBspacerItem\fR ()" +.br +.ti -1c +.BI "int \fBalignment\fR () const" +.br +.ti -1c +.BI "virtual void \fBsetAlignment\fR ( int a )" +.br +.in -1c +.SH DESCRIPTION +The QLayoutItem class provides an abstract item that a QLayout manipulates. +.PP +This is used by custom layouts. +.PP +Pure virtual functions are provided to return information about the layout, including, sizeHint(), minimumSize(), maximumSize() and expanding(). +.PP +The layout's geometry can be set and retrieved with setGeometry() and geometry(), and its alignment with setAlignment() and alignment(). +.PP +isEmpty() returns whether the layout is empty. iterator() returns an iterator for the layout's children. If the concrete item is a QWidget, it can be retrieved using widget(). Similarly for layout() and spacerItem(). +.PP +See also QLayout, Widget Appearance and Style, and Layout Management. +.SH MEMBER FUNCTION DOCUMENTATION +.SH "QLayoutItem::QLayoutItem ( int alignment = 0 )" +Constructs a layout item with an \fIalignment\fR that is a bitwise OR of the Qt::AlignmentFlags. Not all subclasses support alignment. +.SH "QLayoutItem::~QLayoutItem ()\fC [virtual]\fR" +Destroys the QLayoutItem. +.SH "int QLayoutItem::alignment () const" +Returns the alignment of this item. +.SH "QSizePolicy::ExpandData QLayoutItem::expanding () const\fC [pure virtual]\fR" +Implemented in subclasses to return the direction(s) this item" wants" to expand in (if any). +.PP +Reimplemented in QLayout, QSpacerItem, and QWidgetItem. +.SH "QRect QLayoutItem::geometry () const\fC [pure virtual]\fR" +Returns the rectangle covered by this layout item. +.PP +Example: customlayout/border.cpp. +.SH "bool QLayoutItem::hasHeightForWidth () const\fC [virtual]\fR" +Returns TRUE if this layout's preferred height depends on its width; otherwise returns FALSE. The default implementation returns FALSE. +.PP +Reimplement this function in layout managers that support height for width. +.PP +See also heightForWidth() and QWidget::heightForWidth(). +.PP +Examples: +.)l customlayout/border.cpp and customlayout/flow.cpp. +.PP +Reimplemented in QGridLayout and QBoxLayout. +.SH "int QLayoutItem::heightForWidth ( int w ) const\fC [virtual]\fR" +Returns the preferred height for this layout item, given the width \fIw\fR. +.PP +The default implementation returns -1, indicating that the preferred height is independent of the width of the item. Using the function hasHeightForWidth() will typically be much faster than calling this function and testing for -1. +.PP +Reimplement this function in layout managers that support height for width. A typical implementation will look like this: +.PP +.nf +.br + int MyLayout::heightForWidth( int w ) const +.br + { +.br + if ( cache_dirty || cached_width != w ) { +.br + // not all C++ compilers support "mutable" +.br + MyLayout *that = (MyLayout*)this; +.br + int h = calculateHeightForWidth( w ); +.br + that->cached_hfw = h; +.br + return h; +.br + } +.br + return cached_hfw; +.br + } +.br +.fi +.PP +Caching is strongly recommended; without it layout will take exponential time. +.PP +See also hasHeightForWidth(). +.PP +Example: customlayout/flow.cpp. +.PP +Reimplemented in QGridLayout and QBoxLayout. +.SH "void QLayoutItem::invalidate ()\fC [virtual]\fR" +Invalidates any cached information in this layout item. +.PP +Reimplemented in QLayout. +.SH "bool QLayoutItem::isEmpty () const\fC [pure virtual]\fR" +Implemented in subclasses to return whether this item is empty, i.e. whether it contains any widgets. +.PP +Reimplemented in QLayout, QSpacerItem, and QWidgetItem. +.SH "QLayoutIterator QLayoutItem::iterator ()\fC [virtual]\fR" +Returns an iterator over this item's QLayoutItem children. The default implementation returns an empty iterator. +.PP +Reimplement this function in subclasses that can have children. +.PP +Reimplemented in QLayout. +.SH "QLayout * QLayoutItem::layout ()\fC [virtual]\fR" +If this item is a QLayout, it is returned as a QLayout; otherwise 0 is returned. This function provides type-safe casting. +.SH "QSize QLayoutItem::maximumSize () const\fC [pure virtual]\fR" +Implemented in subclasses to return the maximum size of this item. +.PP +Reimplemented in QLayout, QSpacerItem, and QWidgetItem. +.SH "QSize QLayoutItem::minimumSize () const\fC [pure virtual]\fR" +Implemented in subclasses to return the minimum size of this item. +.PP +Examples: +.)l customlayout/border.cpp, customlayout/card.cpp, and customlayout/flow.cpp. +.PP +Reimplemented in QLayout, QSpacerItem, and QWidgetItem. +.SH "void QLayoutItem::setAlignment ( int a )\fC [virtual]\fR" +Sets the alignment of this item to \fIa\fR, which is a bitwise OR of the Qt::AlignmentFlags. Not all subclasses support alignment. +.PP +Example: chart/optionsform.cpp. +.SH "void QLayoutItem::setGeometry ( const QRect & r )\fC [pure virtual]\fR" +Implemented in subclasses to set this item's geometry to \fIr\fR. +.PP +Examples: +.)l customlayout/border.cpp, customlayout/card.cpp, and customlayout/flow.cpp. +.PP +Reimplemented in QLayout, QSpacerItem, and QWidgetItem. +.SH "QSize QLayoutItem::sizeHint () const\fC [pure virtual]\fR" +Implemented in subclasses to return the preferred size of this item. +.PP +Examples: +.)l customlayout/border.cpp, customlayout/card.cpp, and customlayout/flow.cpp. +.PP +Reimplemented in QSpacerItem, QWidgetItem, QGridLayout, and QBoxLayout. +.SH "QSpacerItem * QLayoutItem::spacerItem ()\fC [virtual]\fR" +If this item is a QSpacerItem, it is returned as a QSpacerItem; otherwise 0 is returned. This function provides type-safe casting. +.SH "QWidget * QLayoutItem::widget ()\fC [virtual]\fR" +If this item is a QWidget, it is returned as a QWidget; otherwise 0 is returned. This function provides type-safe casting. +.PP +Reimplemented in QWidgetItem. + +.SH "SEE ALSO" +.BR http://doc.trolltech.com/qlayoutitem.html +.BR http://www.trolltech.com/faq/tech.html +.SH COPYRIGHT +Copyright 1992-2007 Trolltech ASA, http://www.trolltech.com. See the +license file included in the distribution for a complete license +statement. +.SH AUTHOR +Generated automatically from the source code. +.SH BUGS +If you find a bug in Qt, please report it as described in +.BR http://doc.trolltech.com/bughowto.html . +Good bug reports help us to help you. Thank you. +.P +The definitive Qt documentation is provided in HTML format; it is +located at $QTDIR/doc/html and can be read using Qt Assistant or with +a web browser. This man page is provided as a convenience for those +users who prefer man pages, although this format is not officially +supported by Trolltech. +.P +If you find errors in this manual page, please report them to +.BR qt-bugs@trolltech.com . +Please include the name of the manual page (qlayoutitem.3qt) and the Qt +version (3.3.8). |