Drag and Drop Text between tableview

[TheCipo76]

@SGaist i don't know how to do it..

i'm trying to follow this
https://doc.qt.io/archives/4.6/model-view-dnd.html
Using Model/View Classes
it's the correct way?

[VRonin]

@TheCipo76 said in Drag and Drop Text between tableview:

it's the correct way?

No, the correct way is via QAbstractItemModel::canDropMimeData/QAbstractItemModel::dropMimeData but if you use QStandardItemModel then it should already be implemented for free, no need do do anything manually

[TheCipo76]

@VRonin Thank you for response

but..

if i use QStandardItemModel i can't order tableview (i have int value in my database) with a simple click..

where can i find more information about how to do it with QAbstractItemModel as you up-wrote ?

[VRonin]

if i use QStandardItemModel i can't order tableview (i have int value in my database) with a simple click

You can, see QSortFilterProxyModel. Anyway, is the source or the destination being an QSqlTableModel?

[TheCipo76]

@VRonin yes, the source was a QSqlTableModel

[VRonin]

I see, it's a bit fiddly because QStandardItemModel by default appends child items.
Try something like this:

#include <QApplication>
#include <QMimeData>
#include <QStandardItemModel>
#include <QTableView>
#include <QSqlDatabase>
#include <QSqlQuery>
#include <QSqlTableModel>
#include <QHBoxLayout>

class DragSqlTableModel : public QSqlTableModel{
    Q_DISABLE_COPY(DragSqlTableModel)
public:
    using  QSqlTableModel::QSqlTableModel;
    Qt::ItemFlags flags(const QModelIndex &index) const override {return QSqlTableModel::flags(index) | Qt::ItemIsDragEnabled;}

};
class OverwriteModel : public QStandardItemModel{
    Q_DISABLE_COPY(OverwriteModel)
public:
    using QStandardItemModel::QStandardItemModel;
    bool dropMimeData(const QMimeData *data, Qt::DropAction,
                         int, int, const QModelIndex &parent)  override
    {
        const QByteArray mimeData = data->data("application/x-qabstractitemmodeldatalist");
            QDataStream mimeReader(mimeData);
            int junk;
            QMap<int,QVariant> modelData;
            for(;;){
                mimeReader.startTransaction();
                mimeReader >> junk >> junk >> modelData;
                if(!mimeReader.commitTransaction())
                    break;
                setItemData(parent,modelData);
            }
        return true;
    }
};

int main(int argc, char **argv) {
    QApplication app(argc,argv);
    QSqlDatabase db = QSqlDatabase::addDatabase("QSQLITE");
       db.setDatabaseName(":memory:");
   if (!db.open()) return 1;
   QSqlQuery query;
   Q_ASSUME(query.exec("create table person (id int primary key, "
                 "firstname varchar(20), lastname varchar(20))"));
      Q_ASSUME(query.exec("insert into person values(101, 'Danny', 'Young')"));
      Q_ASSUME(query.exec("insert into person values(102, 'Christine', 'Holand')"));
      Q_ASSUME(query.exec("insert into person values(103, 'Lars', 'Gordon')"));
      Q_ASSUME(query.exec("insert into person values(104, 'Roberto', 'Robitaille')"));
      Q_ASSUME(query.exec("insert into person values(105, 'Maria', 'Papadopoulos')"));
    OverwriteModel destination(3,2);

    DragSqlTableModel source(nullptr,db);
    source.setTable("person");
    source.select();
    QWidget mainWid;
    auto sourceView=new QTableView(&mainWid);
    sourceView->setDragEnabled(true);
    sourceView->setModel(&source);
    auto destinationView=new QTableView(&mainWid);
    destinationView->setModel(&destination);
    destinationView->setDragDropMode(QAbstractItemView::DropOnly);
    QHBoxLayout* mainLay = new QHBoxLayout(&mainWid);
    mainLay->addWidget(destinationView);
    mainLay->addWidget(sourceView);
    mainWid.show();
    return app.exec();
}

[TheCipo76]

This post is deleted!

[TheCipo76]

@VRonin Great!! This code works!

now i've to adapt it to my project

Thank you very much!!!

[TheCipo76]

@VRonin i have copied the class definition into my dialog.h

#ifndef PIANIFICAPRODUZIONE_H
#define PIANIFICAPRODUZIONE_H

#include <QDialog>
#include <QSqlTableModel>
#include <QMimeData>
#include <QTableView>
#include <QStandardItemModel>
#include <QSqlDatabase>
#include <QSqlQuery>
#include <QSqlTableModel>


class DragSqlTableModel : public QSqlTableModel{
    Q_DISABLE_COPY(DragSqlTableModel)

public:
    using  QSqlTableModel::QSqlTableModel;
    Qt::ItemFlags flags(const QModelIndex &index) const override {return QSqlTableModel::flags(index) | Qt::ItemIsDragEnabled;}

};

class OverwriteModel : public QStandardItemModel{
    Q_DISABLE_COPY(OverwriteModel)

public:
    using QStandardItemModel::QStandardItemModel;
    bool dropMimeData(const QMimeData *data, Qt::DropAction,
                         int, int, const QModelIndex &parent)  override
    {
        const QByteArray mimeData = data->data("application/x-qabstractitemmodeldatalist");
            QDataStream mimeReader(mimeData);
            int junk;
            QMap<int,QVariant> modelData;
            for(;;){
                mimeReader.startTransaction();
                mimeReader >> junk >> junk >> modelData;
                if(!mimeReader.commitTransaction())
                    break;
                setItemData(parent,modelData);
            }
        return true;
    }
};

namespace Ui {
class pianificaproduzione;
}

class pianificaproduzione : public QDialog
{
    Q_OBJECT

public:
    explicit pianificaproduzione(QWidget *parent = nullptr, const QString &Utente="", const QString &Password="");
    ~pianificaproduzione();

    QString Utente, Password;

private:
    Ui::pianificaproduzione *ui;

    QSqlTableModel *mModel;
    QSqlDatabase mDatabase;
    DragSqlTableModel *source;
    OverwriteModel *model;
};



#endif // PIANIFICAPRODUZIONE_H

i've used DragSqlTableModel instead QSqlTableModel in dialog.cpp

    source = new DragSqlTableModel(this);
    source->setTable("ORDINI");
    source->select();
    ui->tableView_Elenco->setModel(source);
    ui->tableView_Elenco->setEditTriggers(QAbstractItemView::NoEditTriggers);
    ui->tableView_Elenco->setSelectionMode(QAbstractItemView::SingleSelection);
    ui->tableView_Elenco->setDragEnabled(true);
    ui->tableView_Elenco->setDropIndicatorShown(true);
    ui->tableView_Elenco->setSortingEnabled(true); // Ordina al click su Header
    ui->tableView_Elenco->horizontalHeader()->setSectionsClickable(1);
    ui->tableView_Elenco->horizontalHeader()->setSectionResizeMode(QHeaderView::ResizeToContents);
    ui->tableView_Elenco->setColumnHidden(0, true);
    ui->tableView_Elenco->setColumnHidden(1, true);
    ui->tableView_Elenco->setColumnHidden(2, true);
    ui->tableView_Elenco->setColumnHidden(7, true);
    ui->tableView_Elenco->setColumnHidden(9, true);
    ui->tableView_Elenco->setColumnHidden(10, true);
    ui->tableView_Elenco->setColumnHidden(11, true);
    ui->tableView_Elenco->setColumnHidden(12, true);
    ui->tableView_Elenco->setColumnHidden(13, true);
    ui->tableView_Elenco->setColumnHidden(14, true);
    ui->tableView_Elenco->setColumnHidden(15, true);
    ui->tableView_Elenco->setColumnHidden(16, true);
    ui->tableView_Elenco->show();

    // TABLEVIEW PIANO
    //QStandardItemModel *model = new QStandardItemModel(7,6,this); //Rows,Columns
    OverwriteModel *model = new OverwriteModel(7,6,this);
    //INTESTAZIONE COLONNE
    model->setHorizontalHeaderItem(0, new QStandardItem(QString("MACCHINA")));
    model->setHorizontalHeaderItem(1, new QStandardItem(QString("1")));
    model->setHorizontalHeaderItem(2, new QStandardItem(QString("2")));
    model->setHorizontalHeaderItem(3, new QStandardItem(QString("3")));
    model->setHorizontalHeaderItem(4, new QStandardItem(QString("4")));
    model->setHorizontalHeaderItem(5, new QStandardItem(QString("5")));
    model->setHorizontalHeaderItem(6, new QStandardItem(QString("6")));
    // MACCHINE
    model->setItem(0,0,new QStandardItem(QString("PRESSA T63")));
    model->setItem(1,0,new QStandardItem(QString("PRESSA T100")));
    model->setItem(2,0,new QStandardItem(QString("PRESSA T160")));
    model->setItem(3,0,new QStandardItem(QString("PRESSA T199")));
    model->setItem(4,0,new QStandardItem(QString("PRESSA T200")));
    model->setItem(5,0,new QStandardItem(QString("PRESSA T201")));
    model->setItem(6,0,new QStandardItem(QString("TRAPANI")));
    model->setItem(7,0,new QStandardItem(QString("OMERA/PIEGAT")));
    model->setItem(8,0,new QStandardItem(QString("CARTATRICE")));
    model->setItem(9,0,new QStandardItem(QString("TRONCA/CNC")));
    model->setItem(10,0,new QStandardItem(QString("PUNT/MONTA")));
    model->setItem(11,0,new QStandardItem(QString("SALDATRICI")));
    model->setItem(12,0,new QStandardItem(QString("ROBOT")));
    ui->tableView_Piano->horizontalHeader()->setSectionsClickable(1);
    ui->tableView_Piano->horizontalHeader()->setSectionResizeMode(QHeaderView::ResizeToContents);
    ui->tableView_Piano->setModel(model);
    ui->tableView_Elenco->setDragDropMode(QAbstractItemView::DropOnly);

but don't works.. when i try to drag text.. nothing happen..
i don't understand where is the problem..
Any help?

[TheCipo76]

@SGaist Hi, i have tried the VRonin solution but i'm not able to use it in a dialog.. (in mainwindow works very well!)

can you tell me how can i implement drag and drop in the view as you suggested??
or is the same way??

[VRonin]

Works perfectly in a dialog as well:

#include <QApplication>
#include <QMimeData>
#include <QStandardItemModel>
#include <QTableView>
#include <QSqlDatabase>
#include <QSqlQuery>
#include <QSqlTableModel>
#include <QHBoxLayout>
#include <QDialog>
#include <QTimer>

class DragSqlTableModel : public QSqlTableModel{
    Q_DISABLE_COPY(DragSqlTableModel)
public:
    using  QSqlTableModel::QSqlTableModel;
    Qt::ItemFlags flags(const QModelIndex &index) const override {return QSqlTableModel::flags(index) | Qt::ItemIsDragEnabled;}

};
class OverwriteModel : public QStandardItemModel{
    Q_DISABLE_COPY(OverwriteModel)
public:
    using QStandardItemModel::QStandardItemModel;
    bool dropMimeData(const QMimeData *data, Qt::DropAction,
                         int, int, const QModelIndex &parent)  override
    {
        const QByteArray mimeData = data->data("application/x-qabstractitemmodeldatalist");
            QDataStream mimeReader(mimeData);
            int junk;
            QMap<int,QVariant> modelData;
            for(;;){
                mimeReader.startTransaction();
                mimeReader >> junk >> junk >> modelData;
                if(!mimeReader.commitTransaction())
                    break;
                setItemData(parent,modelData);
            }
        return true;
    }
};

int main(int argc, char **argv) {
    QApplication app(argc,argv);
    QSqlDatabase db = QSqlDatabase::addDatabase("QSQLITE");
       db.setDatabaseName(":memory:");
   if (!db.open()) return 1;
   QSqlQuery query;
   Q_ASSUME(query.exec("create table person (id int primary key, "
                 "firstname varchar(20), lastname varchar(20))"));
      Q_ASSUME(query.exec("insert into person values(101, 'Danny', 'Young')"));
      Q_ASSUME(query.exec("insert into person values(102, 'Christine', 'Holand')"));
      Q_ASSUME(query.exec("insert into person values(103, 'Lars', 'Gordon')"));
      Q_ASSUME(query.exec("insert into person values(104, 'Roberto', 'Robitaille')"));
      Q_ASSUME(query.exec("insert into person values(105, 'Maria', 'Papadopoulos')"));
    OverwriteModel destination(3,2);

    DragSqlTableModel source(nullptr,db);
    source.setTable("person");
    source.select();
    QWidget mainWid;
    QDialog* subDialog = new QDialog(&mainWid);
    auto sourceView=new QTableView(subDialog);
    sourceView->setDragEnabled(true);
    sourceView->setModel(&source);
    auto destinationView=new QTableView(subDialog);
    destinationView->setModel(&destination);
    destinationView->setDragDropMode(QAbstractItemView::DropOnly);
    QHBoxLayout* mainLay = new QHBoxLayout(subDialog);
    mainLay->addWidget(destinationView);
    mainLay->addWidget(sourceView);
    mainWid.show();
    QTimer::singleShot(1000,subDialog,&QDialog::exec);
    return app.exec();
}

[TheCipo76]

@VRonin You're right!
i've put your code in new project's main.cpp and works

however i 've wrote that i'm not able to use it..
not that your code don't work.

Now i will retry to use it in my project.

Thank you and thanks to all others who help me every time.