qdrag.cpp

Go to the documentation of this file.

// Copyright (C) 2016 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
 
#include <qdrag.h>
#include "private/qguiapplication_p.h"
#include "qpa/qplatformintegration.h"
#include "qpa/qplatformdrag.h"
#include <qpixmap.h>
#include <qpoint.h>
#include "qdnd_p.h"
 
#include <QtCore/qpointer.h>
 
QT_BEGIN_NAMESPACE
 
QDrag::QDrag(QObject *dragSource)
    : QObject(*new QDragPrivate, dragSource)
{
    Q_D(QDrag);
    d->source = dragSource;
    d->target = nullptr;
    d->data = nullptr;
    d->hotspot = QPoint(-10, -10);
    d->executed_action = Qt::IgnoreAction;
    d->supported_actions = Qt::IgnoreAction;
    d->default_action = Qt::IgnoreAction;
}
 
QDrag::~QDrag()
{
    Q_D(QDrag);
    delete d->data;
}
 
void QDrag::setMimeData(QMimeData *data)
{
    Q_D(QDrag);
    if (d->data == data)
        return;
    if (d->data != nullptr)
        delete d->data;
    d->data = data;
}
 
QMimeData *QDrag::mimeData() const
{
    Q_D(const QDrag);
    return d->data;
}
 
void QDrag::setPixmap(const QPixmap &pixmap)
{
    Q_D(QDrag);
    d->pixmap = pixmap;
}
 
QPixmap QDrag::pixmap() const
{
    Q_D(const QDrag);
    return d->pixmap;
}
 
void QDrag::setHotSpot(const QPoint& hotspot)
{
    Q_D(QDrag);
    d->hotspot = hotspot;
}
 
QPoint QDrag::hotSpot() const
{
    Q_D(const QDrag);
    return d->hotspot;
}
 
QObject *QDrag::source() const
{
    Q_D(const QDrag);
    return d->source;
}
 
QObject *QDrag::target() const
{
    Q_D(const QDrag);
    return d->target;
}
 
Qt::DropAction QDrag::exec(Qt::DropActions supportedActions)
{
    return exec(supportedActions, Qt::IgnoreAction);
}
 
Qt::DropAction QDrag::exec(Qt::DropActions supportedActions, Qt::DropAction defaultDropAction)
{
    Q_D(QDrag);
    if (!d->data) {
        qWarning("QDrag: No mimedata set before starting the drag");
        return d->executed_action;
    }
    Qt::DropAction transformedDefaultDropAction = Qt::IgnoreAction;
 
    if (defaultDropAction == Qt::IgnoreAction) {
        if (supportedActions & Qt::MoveAction) {
            transformedDefaultDropAction = Qt::MoveAction;
        } else if (supportedActions & Qt::CopyAction) {
            transformedDefaultDropAction = Qt::CopyAction;
        } else if (supportedActions & Qt::LinkAction) {
            transformedDefaultDropAction = Qt::LinkAction;
        }
    } else {
        transformedDefaultDropAction = defaultDropAction;
    }
    d->supported_actions = supportedActions;
    d->default_action = transformedDefaultDropAction;
    QPointer<QDrag> self = this;
    auto executed_action = QDragManager::self()->drag(self.data());
    if (self.isNull())
        return Qt::IgnoreAction;
    d->executed_action = executed_action;
    return d->executed_action;
}
 
void QDrag::setDragCursor(const QPixmap &cursor, Qt::DropAction action)
{
    Q_D(QDrag);
    if (cursor.isNull())
        d->customCursors.remove(action);
    else
        d->customCursors[action] = cursor;
}
 
QPixmap QDrag::dragCursor(Qt::DropAction action) const
{
    typedef QMap<Qt::DropAction, QPixmap>::const_iterator Iterator;
 
    Q_D(const QDrag);
    const Iterator it = d->customCursors.constFind(action);
    if (it != d->customCursors.constEnd())
        return it.value();
 
    Qt::CursorShape shape = Qt::ForbiddenCursor;
    switch (action) {
    case Qt::MoveAction:
        shape = Qt::DragMoveCursor;
        break;
    case Qt::CopyAction:
        shape = Qt::DragCopyCursor;
        break;
    case Qt::LinkAction:
        shape = Qt::DragLinkCursor;
        break;
    default:
        shape = Qt::ForbiddenCursor;
    }
    return QGuiApplicationPrivate::instance()->getPixmapCursor(shape);
}
 
Qt::DropActions QDrag::supportedActions() const
{
    Q_D(const QDrag);
    return d->supported_actions;
}
 
 
Qt::DropAction QDrag::defaultAction() const
{
    Q_D(const QDrag);
    return d->default_action;
}
 
void QDrag::cancel()
{
    if (QPlatformDrag *platformDrag = QGuiApplicationPrivate::platformIntegration()->drag())
        platformDrag->cancelDrag();
}
 
QT_END_NAMESPACE
 
#include "moc_qdrag.cpp"