QT implementation drag-and-drop files (with examples, and illustrated, very clear)

Transferred from: http://my.oschina.net/voler/blog/345722

Catalogue [-]

• 0. Source code
• 1. Simple File drag and drop
• 2. Drag and drop complex files
• 3. Use the button to complete the transfer of the list data
• 4. Achieve results by dragging and dropping files
• 1. Simple File drag and drop
• 1. In general, the edit box can receive the file name directly
• 2. Procedures
• 2. Drag and drop complex files
• 1. The key code is as follows
• 2. Procedures
• 3. Use the button to complete the transfer of the list data
• 1. Key code
• 2. Procedures
• 4. Achieve results by dragging and dropping files
• 1. Key code
• 2. (Drag and drop by mouse)

0. source code 1. Simple File drag and drop

Https://github.com/leichaojian/qt/tree/master/drop1

2. Drag and drop complex files

Https://github.com/leichaojian/qt/tree/master/drop

3. Use the button to complete the transfer of the list data

Https://github.com/leichaojian/qt/tree/master/drop3

4. Achieve results by dragging and dropping files

Https://github.com/leichaojian/qt/tree/master/drop4

1. Drag and drop simple files 1. In general, the edit box can receive the file name directly

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mainwindow::mainwindow ( Qwidget *parent):      Qmainwindow (parent),      ui ( new  ui::mainwindow) {      ui-> Setupui ( this      textedit =  new  qtextedit;      setcentralwidget (textEdit);

2. Procedures

2. Drag and drop complex files

If we want to get the file information of the response in the main frame, we must implement the file drag-and-drop operation ourselves.

1. The key code is as follows

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//当用户拖动文件到窗口部件上时候，就会触发dragEnterEvent事件voidMainWindow::dragEnterEvent(QDragEnterEvent *event){    //如果为文件，则支持拖放    if(event->mimeData()->hasFormat("text/uri-list"))        event->acceptProposedAction();}//当用户放下这个文件后，就会触发dropEvent事件voidMainWindow::dropEvent(QDropEvent *event){    //注意：这里如果有多文件存在，意思是用户一下子拖动了多个文件，而不是拖动一个目录    //如果想读取整个目录，则在不同的操作平台下，自己编写函数实现读取整个目录文件名    QList<QUrl> urls = event->mimeData()->urls();    if(urls.isEmpty())        return;    //往文本框中追加文件名    foreach(QUrl url, urls) {        QString file_name = url.toLocalFile();        textEdit->append(file_name);    }}

2. Procedures

3. Use the button to complete the transfer of the list data 1. Key code

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voidDialog::moveCurrentItem(QListWidget *source,                     QListWidget *target){    if(source->currentItem()) {        QListWidgetItem *newItem = source->currentItem()->clone();        target->addItem(newItem);        target->setCurrentItem(newItem);        deletesource->currentItem();    }}

2. Procedures

4. Drag and drop the file to achieve the effect 1. Key code

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voidProjectListWidget::mousePressEvent(QMouseEvent *event){    //获取鼠标按下时候的坐标    if(event->button() == Qt::LeftButton)        startPos = event->pos();    QListWidget::mousePressEvent(event);}voidProjectListWidget::mouseMoveEvent(QMouseEvent *event){    if(event->buttons() & Qt::LeftButton) {        intdistance = (event->pos() - startPos).manhattanLength();        //如果长度大于推荐的拖动起始距离，则认为是拖动(存在用户手抖的情况)        if(distance >= QApplication::startDragDistance())            performDrag();    }    QListWidget::mouseMoveEvent(event);}//有文件拖动到窗口上时，触发此dragEnterEvent事件voidProjectListWidget::dragEnterEvent(QDragEnterEvent *event){    //当为同一个应用程序的一部分时，event->source()返回启动这个拖动窗口部件的指针    ProjectListWidget *source =            qobject_cast<ProjectListWidget *>(event->source());    if(source && source != this) {        //确认是一个移动的操作        event->setDropAction(Qt::MoveAction);        event->accept();    }}voidProjectListWidget::dragMoveEvent(QDragMoveEvent *event){    ProjectListWidget *source =            qobject_cast<ProjectListWidget *>(event->source());    if (source && source != this) {        event->setDropAction(Qt::MoveAction);        event->accept();    }}voidProjectListWidget::dropEvent(QDropEvent *event){    ProjectListWidget *source =            qobject_cast<ProjectListWidget *>(event->source());    if(source && source != this) {        //得到数据并增加到列表中        addItem(event->mimeData()->text());        event->setDropAction(Qt::MoveAction);        event->accept();    }}voidProjectListWidget::performDrag(){    //当前被拖动的选项    QListWidgetItem *item = currentItem();    if(item) {        QMimeData *mimeData = newQMimeData;        mimeData->setText(item->text());        QDrag *drag = newQDrag(this);        drag->setMimeData(mimeData);        drag->setPixmap(QPixmap(":/images/person.png"));        //进行拖动操作        if(drag->exec(Qt::MoveAction) == Qt::MoveAction)            deleteitem;    }}

2. (Drag and drop by mouse)

http://blog.csdn.net/emdfans/article/details/41721955

QT implementation drag-and-drop files (with examples, and illustrated, very clear)