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50
51#include "droparea.h"
52
53#include <QDragEnterEvent>
54#include <QMimeData>
55
56//! [DropArea constructor]
57DropArea::DropArea(QWidget *parent)
58 : QLabel(parent)
59{
60 setMinimumSize(minw: 200, minh: 200);
61 setFrameStyle(QFrame::Sunken | QFrame::StyledPanel);
62 setAlignment(Qt::AlignCenter);
63 setAcceptDrops(true);
64 setAutoFillBackground(true);
65 clear();
66}
67//! [DropArea constructor]
68
69//! [dragEnterEvent() function]
70void DropArea::dragEnterEvent(QDragEnterEvent *event)
71{
72 setText(tr(s: "<drop content>"));
73 setBackgroundRole(QPalette::Highlight);
74
75 event->acceptProposedAction();
76 emit changed(mimeData: event->mimeData());
77}
78//! [dragEnterEvent() function]
79
80//! [dragMoveEvent() function]
81void DropArea::dragMoveEvent(QDragMoveEvent *event)
82{
83 event->acceptProposedAction();
84}
85//! [dragMoveEvent() function]
86
87//! [dropEvent() function part1]
88void DropArea::dropEvent(QDropEvent *event)
89{
90 const QMimeData *mimeData = event->mimeData();
91//! [dropEvent() function part1]
92
93//! [dropEvent() function part2]
94 if (mimeData->hasImage()) {
95 setPixmap(qvariant_cast<QPixmap>(v: mimeData->imageData()));
96 } else if (mimeData->hasFormat(mimetype: QLatin1String("text/markdown"))) {
97 setText(QString::fromUtf8(str: mimeData->data(mimetype: QLatin1String("text/markdown"))));
98 setTextFormat(Qt::MarkdownText);
99 } else if (mimeData->hasHtml()) {
100 setText(mimeData->html());
101 setTextFormat(Qt::RichText);
102 } else if (mimeData->hasText()) {
103 setText(mimeData->text());
104 setTextFormat(Qt::PlainText);
105 } else if (mimeData->hasUrls()) {
106 QList<QUrl> urlList = mimeData->urls();
107 QString text;
108 for (int i = 0; i < urlList.size() && i < 32; ++i)
109 text += urlList.at(i).path() + QLatin1Char('\n');
110 setText(text);
111 } else {
112 setText(tr(s: "Cannot display data"));
113 }
114//! [dropEvent() function part2]
115
116//! [dropEvent() function part3]
117 setBackgroundRole(QPalette::Dark);
118 event->acceptProposedAction();
119}
120//! [dropEvent() function part3]
121
122//! [dragLeaveEvent() function]
123void DropArea::dragLeaveEvent(QDragLeaveEvent *event)
124{
125 clear();
126 event->accept();
127}
128//! [dragLeaveEvent() function]
129
130//! [clear() function]
131void DropArea::clear()
132{
133 setText(tr(s: "<drop content>"));
134 setBackgroundRole(QPalette::Dark);
135
136 emit changed();
137}
138//! [clear() function]
139

source code of qtbase/examples/widgets/draganddrop/dropsite/droparea.cpp