droparea.cpp Example File

draganddrop/dropsite/droparea.cpp
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#include "droparea.h" #include <QDragEnterEvent> #include <QMimeData> DropArea::DropArea(QWidget *parent) : QLabel(parent) { setMinimumSize(200, 200); setFrameStyle(QFrame::Sunken | QFrame::StyledPanel); setAlignment(Qt::AlignCenter); setAcceptDrops(true); setAutoFillBackground(true); clear(); } void DropArea::dragEnterEvent(QDragEnterEvent *event) { setText(tr("<drop content>")); setBackgroundRole(QPalette::Highlight); event->acceptProposedAction(); emit changed(event->mimeData()); } void DropArea::dragMoveEvent(QDragMoveEvent *event) { event->acceptProposedAction(); } void DropArea::dropEvent(QDropEvent *event) { const QMimeData *mimeData = event->mimeData(); if (mimeData->hasImage()) { setPixmap(qvariant_cast<QPixmap>(mimeData->imageData())); } 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")); } setBackgroundRole(QPalette::Dark); event->acceptProposedAction(); } void DropArea::dragLeaveEvent(QDragLeaveEvent *event) { clear(); event->accept(); } void DropArea::clear() { setText(tr("<drop content>")); setBackgroundRole(QPalette::Dark); emit changed(); }