qt5base-lts/examples/widgets/draganddrop/dropsite/droparea.cpp
Shawn Rutledge 4edcea762d DropSite example: support markdown
If the mime data includes text/markdown, display it decoded in the QLabel,
and also display the raw markdown in the table below.  QLabel supports
markdown since 51cbd5288c.

Ideally we should add proper support for markdown to QMimeData, but
it's too late to do that for Qt 5.

Pick-to: 5.15
Change-Id: I2a9998e4b239658fe49f39786e7c4fdd0c08b21a
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@qt.io>
2020-11-02 16:08:36 +01:00

139 lines
4.7 KiB
C++

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#include "droparea.h"
#include <QDragEnterEvent>
#include <QMimeData>
//! [DropArea constructor]
DropArea::DropArea(QWidget *parent)
: QLabel(parent)
{
setMinimumSize(200, 200);
setFrameStyle(QFrame::Sunken | QFrame::StyledPanel);
setAlignment(Qt::AlignCenter);
setAcceptDrops(true);
setAutoFillBackground(true);
clear();
}
//! [DropArea constructor]
//! [dragEnterEvent() function]
void DropArea::dragEnterEvent(QDragEnterEvent *event)
{
setText(tr("<drop content>"));
setBackgroundRole(QPalette::Highlight);
event->acceptProposedAction();
emit changed(event->mimeData());
}
//! [dragEnterEvent() function]
//! [dragMoveEvent() function]
void DropArea::dragMoveEvent(QDragMoveEvent *event)
{
event->acceptProposedAction();
}
//! [dragMoveEvent() function]
//! [dropEvent() function part1]
void DropArea::dropEvent(QDropEvent *event)
{
const QMimeData *mimeData = event->mimeData();
//! [dropEvent() function part1]
//! [dropEvent() function part2]
if (mimeData->hasImage()) {
setPixmap(qvariant_cast<QPixmap>(mimeData->imageData()));
} else if (mimeData->hasFormat(QLatin1String("text/markdown"))) {
setText(QString::fromUtf8(mimeData->data(QLatin1String("text/markdown"))));
setTextFormat(Qt::MarkdownText);
} else if (mimeData->hasHtml()) {
setText(mimeData->html());
setTextFormat(Qt::RichText);
} else if (mimeData->hasText()) {
setText(mimeData->text());
setTextFormat(Qt::PlainText);
} else if (mimeData->hasUrls()) {
QList<QUrl> urlList = mimeData->urls();
QString text;
for (int i = 0; i < urlList.size() && i < 32; ++i)
text += urlList.at(i).path() + QLatin1Char('\n');
setText(text);
} else {
setText(tr("Cannot display data"));
}
//! [dropEvent() function part2]
//! [dropEvent() function part3]
setBackgroundRole(QPalette::Dark);
event->acceptProposedAction();
}
//! [dropEvent() function part3]
//! [dragLeaveEvent() function]
void DropArea::dragLeaveEvent(QDragLeaveEvent *event)
{
clear();
event->accept();
}
//! [dragLeaveEvent() function]
//! [clear() function]
void DropArea::clear()
{
setText(tr("<drop content>"));
setBackgroundRole(QPalette::Dark);
emit changed();
}
//! [clear() function]