source: trunk/src/gui/kernel/qdrag.cpp@ 439

Last change on this file since 439 was 2, checked in by Dmitry A. Kuminov, 16 years ago

Initially imported qt-all-opensource-src-4.5.1 from Trolltech.
File size: 11.5 KB
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41
42#include <qwidget.h>
43#include <qdrag.h>
44#include <qpixmap.h>
45#include <qpoint.h>
46#include "qdnd_p.h"
47
48#ifndef QT_NO_DRAGANDDROP
49
50QT_BEGIN_NAMESPACE
51
52/*!
53 \class QDrag
54 \brief The QDrag class provides support for MIME-based drag and drop data
55 transfer.
56
57 Drag and drop is an intuitive way for users to copy or move data around in an
58 application, and is used in many desktop environments as a mechanism for copying
59 data between applications. Drag and drop support in Qt is centered around the
60 QDrag class that handles most of the details of a drag and drop operation.
61
62 The data to be transferred by the drag and drop operation is contained in a
63 QMimeData object. This is specified with the setMimeData() function in the
64 following way:
65
66 \snippet doc/src/snippets/dragging/mainwindow.cpp 1
67
68 Note that setMimeData() assigns ownership of the QMimeData object to the
69 QDrag object. The QDrag must be constructed on the heap with a parent QWidget
70 to ensure that Qt can clean up after the drag and drop operation has been
71 completed.
72
73 A pixmap can be used to represent the data while the drag is in
74 progress, and will move with the cursor to the drop target. This
75 pixmap typically shows an icon that represents the MIME type of
76 the data being transferred, but any pixmap can be set with