Drag and Drop items in QListWidget

[tommynator128]

Hello,

i've got an list widget that should be able to accept file drops and be able of drag and drop the items into the desired order. if i do all this stuff and remove my own drop event functions it still duplicates the item. if i got my own drop event function there is no possibility of dropping files. how should i do this?

thanks
tommy

[JohannesMunk]

Hi Tommy!

I find it hard to guess what you might have done wrong. Could you post your source code? Preferably just the relevant but still compilable parts.

Johannes

[tommynator128]

.h

#ifndef FILELIST_H
#define FILELIST_H
 
#include <QtGui>
#include <QtCore>
 
 
class FileList : public QListWidget
{
	Q_OBJECT
 
public:
	FileList();
 
protected:
	void dragEnterEvent(QDragEnterEvent *event);
    	void dragMoveEvent(QDragMoveEvent *event);
    	void dragLeaveEvent(QDragLeaveEvent *event);
    	void dropEvent(QDropEvent *event);
};
 
#endif

#ifndef FILELIST_H
#define FILELIST_H

#include <QtGui>
#include <QtCore>


class FileList : public QListWidget
{
	Q_OBJECT
	
public:
	FileList();
	
protected:
	void dragEnterEvent(QDragEnterEvent *event);
    	void dragMoveEvent(QDragMoveEvent *event);
    	void dragLeaveEvent(QDragLeaveEvent *event);
    	void dropEvent(QDropEvent *event);
};

#endif

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.cpp

#include <QtGui>
 
#include "fileList.h"
 
 
 
FileList::FileList()
{
	setAlternatingRowColors(true);
	dropHintItem = new QListWidgetItem;
	dropHintItem->setText("Drop Files here...");
	dropHintItem->setFlags(dropHintItem->flags() & ~(Qt::ItemIsDropEnabled));
	insertItem(0, dropHintItem);
	setAcceptDrops(true);
}
 
void FileList::dragEnterEvent(QDragEnterEvent *event)
{
    event->acceptProposedAction();
}
 
void FileList::dragMoveEvent(QDragMoveEvent *event)
{
    event->acceptProposedAction();
}
 
void FileList::dropEvent(QDropEvent *event) {
    const QMimeData *mimeData = event->mimeData();
    if (mimeData->hasUrls()) {
       //Insert the URLs and set flags to Qt::ItemIsDragEnabled | Qt::ItemIsDropEnabled | defaultFlags;
    }
    event->acceptProposedAction();
}
 
void FileList::dragLeaveEvent(QDragLeaveEvent *event)
{
    event->accept();
}

#include <QtGui>

#include "fileList.h"



FileList::FileList()
{
	setAlternatingRowColors(true);
	dropHintItem = new QListWidgetItem;
	dropHintItem->setText("Drop Files here...");
	dropHintItem->setFlags(dropHintItem->flags() & ~(Qt::ItemIsDropEnabled));
	insertItem(0, dropHintItem);
	setAcceptDrops(true);
}

void FileList::dragEnterEvent(QDragEnterEvent *event)
{
    event->acceptProposedAction();
}

void FileList::dragMoveEvent(QDragMoveEvent *event)
{
    event->acceptProposedAction();
}

void FileList::dropEvent(QDropEvent *event) {
    const QMimeData *mimeData = event->mimeData();
    if (mimeData->hasUrls()) {
       //Insert the URLs and set flags to Qt::ItemIsDragEnabled | Qt::ItemIsDropEnabled | defaultFlags;
    }
    event->acceptProposedAction();
}

void FileList::dragLeaveEvent(QDragLeaveEvent *event)
{
    event->accept();
}

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[JohannesMunk]

Hi!

Deep in the docs I found: http://doc.trolltech.com/latest/mode...ith-item-views

The following seems to do what you want:

#include "FileList.h"
 
FileList::FileList()
{
    setAcceptDrops(true);
    setDragEnabled(true);
 
    setSelectionMode(QAbstractItemView::SingleSelection);
    setDropIndicatorShown(true);
    setDragDropMode(QAbstractItemView::InternalMove);
 
    setAlternatingRowColors(true);
 
    dropHintItem = new QListWidgetItem("Drop Files here...",this);
}
 
void FileList::dragEnterEvent(QDragEnterEvent *event)
{
    if (event->mimeData()->hasUrls())
    {
        event->acceptProposedAction();
    } else {
        QListWidget::dragEnterEvent(event);
    }
}
 
void FileList::dragMoveEvent(QDragMoveEvent *event)
{
    if (event->mimeData()->hasUrls())
    {
        event->acceptProposedAction();
    } else {
        QListWidget::dragMoveEvent(event);
    }
}
 
void FileList::dropEvent(QDropEvent *event)
{
    if (event->mimeData()->hasUrls())
    {
        QList<QUrl> urls = event->mimeData()->urls();
        if (!urls.isEmpty())
        {
            if (dropHintItem)
            {
                delete dropHintItem;
                dropHintItem = 0;
            }
            QUrl url;
            foreach (url,urls)
            {
                new QListWidgetItem(url.toLocalFile(),this);
            }
        }
        event->acceptProposedAction();
    }
    QListWidget::dropEvent(event);
}

#include "FileList.h"

FileList::FileList()
{
    setAcceptDrops(true);
    setDragEnabled(true);

    setSelectionMode(QAbstractItemView::SingleSelection);
    setDropIndicatorShown(true);
    setDragDropMode(QAbstractItemView::InternalMove);

    setAlternatingRowColors(true);

    dropHintItem = new QListWidgetItem("Drop Files here...",this);
}

void FileList::dragEnterEvent(QDragEnterEvent *event)
{
    if (event->mimeData()->hasUrls())
    {
        event->acceptProposedAction();
    } else {
        QListWidget::dragEnterEvent(event);
    }
}

void FileList::dragMoveEvent(QDragMoveEvent *event)
{
    if (event->mimeData()->hasUrls())
    {
        event->acceptProposedAction();
    } else {
        QListWidget::dragMoveEvent(event);
    }
}

void FileList::dropEvent(QDropEvent *event)
{
    if (event->mimeData()->hasUrls())
    {
        QList<QUrl> urls = event->mimeData()->urls();
        if (!urls.isEmpty())
        {
            if (dropHintItem)
            {
                delete dropHintItem;
                dropHintItem = 0;
            }
            QUrl url;
            foreach (url,urls)
            {
                new QListWidgetItem(url.toLocalFile(),this);
            }
        }
        event->acceptProposedAction();
    }
    QListWidget::dropEvent(event);
}

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Joh

[abeinoe]

thank..it's the solution for my problem on mac os. my old code worked fine on windows but not in mac.