Qt Copy and Paste within QTableView not working - c++

Question

I am designing a user interface with several functions. On the .ui I have a QTableView. After right click on the table view I open a dialog with the same QTableView so in this way is easier to visualize data.
After Trying to copy and paste some of the values say, from a cell to another or from a column to another column I have a weird behavior that I don't know how to solve. Below I try to copy ctrl+C the selected cell:
And paste it ctrl+V I obtain a weird behavior:
For some reasons I am copiyng the header "longitude" on the second row instead of the number 24. Additionally the number 200 is pushed below.
This code also allows to copy and paste from the QTableView to an Excel file, this functions works well but I decided to include it in the explanation so you know how I handle all the loops.
editdialog.h
private:
Ui::editLeftTableDialog *ui;
QSqlTableModel *mModel;
QAction *mActionAppendRow;
QAction *mActionDeleteRow;
protected:
void keyPressEvent(QKeyEvent *event);
editdialog.cpp
void editLeftTableDialog::keyPressEvent(QKeyEvent *event)
{
{
QAbstractItemModel * modelRemoveAdd = ui->tableViewLeft->model();
QItemSelectionModel *selectionModel = ui->tableViewLeft->selectionModel();
QModelIndexList selectedRows = selectionModel->selectedRows();
QAbstractItemModel * modelNew = ui->tableViewLeft->model();
QItemSelectionModel *selectedIndexes = ui->tableViewLeft->selectionModel();
QModelIndexList selectedInd = selectedIndexes->selectedIndexes();
// Make sure one row is selected
if(!selectedRows.isEmpty())
{
if(event->key() == Qt::Key_Insert)
mModel->insertRows(selectedRows.at(0).row(),
selectedRows.size());
else if(event->key() == Qt::Key_Delete)
mModel->removeRows(selectedRows.at(0).row(),
selectedRows.size());
}
// Make sure one cell selected
if(!selectedInd.isEmpty())
{
if(event->key() == Qt::Key_Delete)
foreach(QModelIndex index, selectedInd)
mModel->setData(index, QString());
else if(event->matches(QKeySequence::Copy))
{
QString text;
QItemSelectionRange range = ui->tableViewLeft->selectionModel()->selection().first();
for(auto i = range.top(); i <= range.bottom(); ++i)
{
QStringList rowContents;
for(auto j = range.left(); j <= range.right(); ++j)
rowContents << mModel->index(i,j).data().toString();
text += rowContents.join("\t");
text += "\n";
}
QApplication::clipboard()->setText(text);
}
else if(event->matches(QKeySequence::Paste))
{
QString text = QApplication::clipboard()->text();
QStringList rowContents = text.split("\n", QString::SkipEmptyParts);
QModelIndex initIndex = ui->tableViewLeft->selectionModel()->selectedIndexes().at(0);
auto initRow = initIndex.row();
auto initCol = initIndex.column();
for(auto i = 0; i < rowContents.size(); i++)
{
QStringList columnContents = rowContents.at(i).split("\t");
for(auto j = 0; j < columnContents.size(); j++)
{
mModel->setData(mModel->index(initRow + i, initCol + j), columnContents.at(j));
}
}
}
}
}
// Copy from QTableView to an Excel or CSV file happens here and works well
QAbstractItemModel * model = ui->tableViewLeft->model();
QItemSelectionModel *selection = ui->tableViewLeft->selectionModel();
QModelIndexList indices = selection->selectedIndexes();
if(indices.isEmpty())
return;
QMap<int, bool> selectedColumnsMap;
Q_FOREACH (QModelIndex current, indices)
{
selectedColumnsMap[current.column()] = true;
}
QList<int> selectedColumns = selectedColumnsMap.uniqueKeys();
int minCol = selectedColumns.first();
// prepend headers for selected columns
QString selectedText;
Q_FOREACH (int column, selectedColumns)
{
selectedText += ui->tableViewLeft->model()->headerData(column, Qt::Horizontal, Qt::DisplayRole).toString();
if(column != selectedColumns.last())
selectedText += QLatin1Char('\t');
}
selectedText += QLatin1Char('\n');
qSort(indices);
int lastRow = indices.first().row();
int lastColumn = minCol;
Q_FOREACH(QModelIndex current, indices)
{
if(current.row() != lastRow)
{
selectedText += QLatin1Char('\n');
lastColumn = minCol;
lastRow = current.row();
}
if(current.column() != lastColumn)
{
for(int i = 0; i < current.column() - lastColumn; ++i)
selectedText += QLatin1Char('\t');
lastColumn = current.column();
}
selectedText += ui->tableViewLeft->model()->data(current).toString();
}
selectedText += QLatin1Char('\n');
QApplication::clipboard()->setText(selectedText);
}

Answer 1

A messy code always brings problems, so I'm not going to analyze it but I'm going to propose an appropriate method where we create a function for each task, and instead of using keyPressEvent you can use a QShorcut:
editlefttabledialog.h
#ifndef EDITLEFTTABLEDIALOG_H
#define EDITLEFTTABLEDIALOG_H
#include <QDialog>
class QSqlTableModel;
namespace Ui {
class EditLeftTableDialog;
}
class EditLeftTableDialog : public QDialog
{
Q_OBJECT
public:
explicit EditLeftTableDialog(QWidget *parent = nullptr);
~EditLeftTableDialog();
private slots:
void copy();
void paste();
private:
Ui::EditLeftTableDialog *ui;
QSqlTableModel *mModel;
};
#endif // EDITLEFTTABLEDIALOG_H
editlefttabledialog.cpp
#include "editlefttabledialog.h"
#include "ui_editlefttabledialog.h"
#include <QShortcut>
#include <QSqlTableModel>
#include <QClipboard>
EditLeftTableDialog::EditLeftTableDialog(QWidget *parent) :
QDialog(parent),
ui(new Ui::EditLeftTableDialog)
{
ui->setupUi(this);
mModel = new QSqlTableModel(this);
mModel->setTable("test_table");
mModel->select();
ui->tableViewLeft->setModel(mModel);
QShortcut *shortcut_copy = new QShortcut(QKeySequence::Copy, ui->tableViewLeft);
connect(shortcut_copy, &QShortcut::activated, this, &EditLeftTableDialog::copy);
QShortcut *shortcut_paste = new QShortcut(QKeySequence::Paste, ui->tableViewLeft);
connect(shortcut_paste, &QShortcut::activated, this, &EditLeftTableDialog::paste);
}
EditLeftTableDialog::~EditLeftTableDialog()
{
delete ui;
}
void EditLeftTableDialog::copy()
{
QString text;
QItemSelectionRange selection_range = ui->tableViewLeft->selectionModel()->selection().first();
for(int i=selection_range.top(); i <= selection_range.bottom(); i++){
QStringList row_content;
for(int j= selection_range.left(); j <= selection_range.right(); j++){
row_content << mModel->index(i,j).data().toString();
}
text += row_content.join(QChar('\t')) + QChar('\n');
}
QApplication::clipboard()->setText(text);
}
void EditLeftTableDialog::paste()
{
QModelIndex start = ui->tableViewLeft->selectionModel()->selectedIndexes().first();
QString text = QApplication::clipboard()->text();
int i=0, j=0;
for(const QString & row_string: text.split("\n", QString::SkipEmptyParts)){
j=0;
for(const QString & col: row_string.split("\t", QString::SkipEmptyParts)){
QModelIndex ix = mModel->index(start.row() + i , start.column()+ j);
if(ix.isValid()){
ui->tableViewLeft->model()->setData(ix, col);
mModel->submit();
}
j++;
}
i++;
}
}