qicondrag.3qt

linux下GUI编程工具qt的在线连接帮助手册

'\" t
.TH QIconDrag 3qt "11 October 2001" "Trolltech AS" \" -*- nroff -*-
.\" Copyright 1992-2001 Trolltech AS.  All rights reserved.  See the
.\" license file included in the distribution for a complete license
.\" statement.
.\"
.ad l
.nh
.SH NAME
QIconDrag \- Supports drag and drop operations within a QIconView
.PP
\fC#include <qiconview.h>\fR
.PP
Inherits QDragObject.
.PP
.SS "Public Members"
.in +1c
.ti -1c
.BI "virtual \fB~QIconDrag\fR ()"
.br
.ti -1c
.BI "void \fBappend\fR ( const QIconDragItem & i, const QRect & pr, const QRect & tr )"
.br
.ti -1c
.BI "virtual QByteArray \fBencodedData\fR ( const char * mime ) const"
.br
.in -1c
.SS "Static Public Members"
.in +1c
.ti -1c
.BI "bool \fBcanDecode\fR ( QMimeSource * e )"
.br
.in -1c
.SH DESCRIPTION
The QIconDrag class supports drag and drop operations within a QIconView.
.PP
A QIconDrag object is used to maintain information about the positions of dragged items and data associated with the dragged items. QIconViews are able to use this information to paint the dragged items in the correct positions. Internally QIconDrag stores the data associated with drag items in QIconDragItem objects.
.PP
If you want to use the extended drag-and-drop functionality of QIconView create a QIconDrag object in a reimplementation of QIconView::dragObject(). Then create a QIconDragItem for each item which should be dragged, set the data it represents with QIconDragItem::setData(), and add each QIconDragItem to the drag object using append().
.PP
The data in QIconDragItems is stored in a QByteArray and is mime-typed (see QMimeSource and the Drag and Drop overview). If you want to use your own mime-types derive a class from QIconDrag and reimplement format(), encodedData() and canDecode().
.PP
The fileiconview example program demonstrates the use of the QIconDrag class including subclassing and reimplementing dragObject(), format(), encodedData() and canDecode(). See the files \fCqt/examples/fileiconview/qfileiconview.h\fR and \fCqt/examples/fileiconview/qfileiconview.cpp\fR.
.PP
See also QMimeSource::format() and Drag And Drop Classes.
.SH MEMBER FUNCTION DOCUMENTATION
.SH "QIconDrag::~QIconDrag ()\fC [virtual]\fR"
Destructor.
.SH "void QIconDrag::append ( const QIconDragItem & i, const QRect & pr, const QRect & tr )"
Append the QIconDragItem, \fIi\fR, to the QIconDrag object's list of items. You must also supply the geometry of the pixmap, \fIpr\fR, and of the textual caption, \fItr\fR.
.PP
See also QIconDragItem.
.PP
Example: fileiconview/qfileiconview.cpp.
.SH "bool QIconDrag::canDecode ( QMimeSource * e )\fC [static]\fR"
Returns TRUE if \fIe\fR can be decoded by the QIconDrag, otherwise return FALSE.
.PP
Example: fileiconview/qfileiconview.cpp.
.SH "QByteArray QIconDrag::encodedData ( const char * mime ) const\fC [virtual]\fR"
Returns the encoded data of the drag object if \fImime\fR is application/x-qiconlist.
.PP
Example: fileiconview/qfileiconview.cpp.
.PP
Reimplemented from QMimeSource.

.SH "SEE ALSO"
.BR http://doc.trolltech.com/qicondrag.html
.BR http://www.trolltech.com/faq/tech.html
.SH COPYRIGHT
Copyright 1992-2001 Trolltech AS, 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 [e-mail] .
Please include the name of the manual page (qicondrag.3qt) and the Qt
version (3.0.0).