Always show a QComboBox in a cell of a QTableView - c++

I have a QTableView with an associated model. I want to have a QComboBox in each cell of the third column.
I used a QItemDelegate as shown in this page : https://wiki.qt.io/Combo_Boxes_in_Item_Views.
It works but the combo box is only shown after double clicking in the cell, the user has to click again to show the list of possible values. This is a bit inconvenient.
Is there a way to make the combo boxes always visible ?
I'm trying with openPersistentEditor method, but it does not work right now ...
there is a bit of code close to my code (ComboBoxItemDelegate is the same than the exemple linked before):
MonWidget::MonWidget() : _ui(new Ui::MonWidget())
{
// ...
// Links Model
_linksModel = new QStandardItemModel(this);
// Links Headers
QStringList linksTableViewHeader << "Name" << "Path" << "Version";
_linksModel->setHorizontalHeaderLabels(linksTableViewHeader) ;
// Create itemDelegate for linksView
_itemDelegate = new ComboBoxItemDelegate(_ui->_linksView);
// Set the links model on the links table view
_ui->_linksView->setModel(_linksModel);
_ui->_linksView->horizontalHeader()->setSectionResizeMode(QHeaderView::Interactive);
_ui->_linksView->horizontalHeader()->setStretchLastSection(true);
_ui->_linksView->horizontalHeader()->setMinimumSectionSize(100);
_ui->_linksView->setSelectionBehavior(QAbstractItemView::SelectRows);
_ui->_linksView->setItemDelegate(_itemDelegate);
}
// AddLinksInListView : method called when I add some rows ...
void MonWidget::AddLinksInListView(QList<DataItem*> listLinks)
{
int j=0;
int initialLinksNumber = _linksModel->rowCount();
// For each link, add a row with the link information
for (int row=initialLinksNumber; row<(initialLinksNumber + listLinks.size()) ; row++)
{
for (int column = 0; column < _linksModel->columnCount(); column++) {
//item used to display information for each column in the table view of links contained in the collection
QStandardItem *item=0;
switch(column)
{
case MonWidget::NAME:
{
item = new QStandardItem(listLinks.at(j)->data(MonWidget::NAME).toString());
_linksModel->setItem(row, column, item);
break;
}
case MonWidget::PATH:
{
item = new QStandardItem(listLinks.at(j)->data(MonWidget::PATH).toString());
_linksModel->setItem(row, column, item);
break;
}
case MonWidget::VERSION:
{
item = new QStandardItem(listLinks.at(j)->data(MonWidget::PATH).toString());
_linksModel->setItem(row, column, item);
_ui->_linksView->openPersistentEditor(_linksModel->index(row, column));
break;
}
}
}
j++;
}
}

Yes, there is a way, using openPersistentEditor. Assuming your model is named myModel:
YourDelegate* comboDelegate = new YourDelegate(this);
setItemDelegateForColumn(2, comboDelegate); // delegate set for the third column
...
// when adding a new line, use this.
// The combo box will be always visible
openPersistentEditor(myModel->index(iRow, 1));

Related

Selecting a row in QTableWidget with conditions to disable pushButton

I'm not sure if the title is correct but this is the situation:
When a row is selected and contains Application Status of FULL_MEMBER,
A pushButton is enabled else it is disabled.
You have to get the text of the item (cell) in the fifth column of the selected row, each time the selection changes.
Have a slot like this in your widget:
private slots:
void tableSelectionChanged();
In the widget constructor, connect it to the table widget signal itemSelectionChanged:
connect(ui->tableWidget, SIGNAL(itemSelectionChanged()), this, SLOT(tableSelectionChanged()));
The slot definition is like this:
//retrieve a list of all selected rows
QModelIndexList list = ui->tableWidget->selectionModel()->selectedRows();
if(list.size() > 0)
{
//retrieve the index of the first (and only, maybe?) selected row
int row = list[0].row();
const int col = 4; //Application Status column id
QTableWidgetItem * item = ui->tableWidget->item(row, col); //the item we want to inspect
ui->pushButton->setEnabled( item->text() == "FULL_MEMBER" );
}

Adjusting QSqlTableModel for a QTreeView

I'm trying to put a MySQL table into a treeView.
Each entry has three values in the database - id, text, parentId.
This treeView needs to be editable so I really like the QSqlTableModel approach, as the functionality to save back to database is already built in.
Now, the treeView is showing all entries in the same line, of course, and I need a hierarchy. What would be the best way to build this hierarchy, while maintaining the editing and saving capabilities?
(I'm using MySQL.)
mainwindow.h
private: QSqlTableModel* goalModel;
mainwindow.cpp
(this makes a flat table hierarchy. the table is filtered based on which entry is clicked in another table)
void MainWindow::on_tableViewGoals_clicked(const QModelIndex &index)
{
goalModel = new QSqlTableModel(this);
goalModel->setTable("goals");
//Gets the id from the clicked entry to use as filter
QString idGoals = index.sibling(row,0).data().toString();
goalModel->setFilter( "id_goals=" + idGoals );
goalModel->setEditStrategy(QSqlTableModel::OnRowChange);
goalModel->select();
ui->treeView->setModel(goalModel);
...
I tried this. It's wrong, but I don't really know why. (the third column contains the parentId value, if the entry has it)
for (int row = 0; row < goalModel->rowCount(); ++row)
{
//if the entry has a value over 0 in the parentId column
if (goalModel->index(row,2).data().toInt() > 0)
{
//get number in column 2
int parentId;
parentId = goalModel->index(row,2).data().toInt();
QModelIndex newChild = goalModel->index(row,0);
//find QModelIndex row with matching number in column 0
for (int row = 0; row < goalModel->rowCount(); ++row)
{
if (goalModel->index(row,0).data().toInt() == parentId )
{
//make this entry that entry's child
QModelIndex newParent = goalModel->index(row,0);
newChild = goalModel->index(0,0,newParent);
}
}
}
}
All indexes are already made, so no need to make new ones, just assign a parent to all those who have one. How best to do that?

How to get current row of QTableWidget if I clicked on its child?

I have created a QTableWidget in which I've used setCellWidget(QWidget*). I've set QLineEdit in the cell widget. I've also created a delete button and clicking that button sends a signal to the function deleteRow. I've also used a function currentRow() to get the current row, but it returns -1 because of the QLineEdit. The code snippet is below.
void createTable() {
m_table = new QTableWidget(QDialog); //member variable
for (int i = 0; i < 3; i++)
{
QLineEdit *lineEdit = new QLineEdit(m_table);
m_table->setCellWidget(i, 0, lineEdit);
}
QPushButton *deleteBut = new QPushButton(QDiaolg);
connect(deleteBut, SIGNAL(clicked()), QDialog, SLOT(editRow()));
}
editRow() {
int row = m_table->currentRow(); // This gives -1
m_table->remove(row);
}
In above scenario I click in the QLineEdit and then click on the button delete. Please help me out with a solution.
Just tried it here, it seems that currentRow of the table returns -1 when clicking the button right after program start, and when first selecting a cell, then selecting the QLineEdit and then clicking the button, the correct row is returned.
I would do the following as a workaround: Save the row number in the QLineEdit, e.g. by using QObject::setProperty:
QLineEdit *lineEdit = new QLineEdit(m_table);
lineEdit->setProperty("row", i);
m_table->setCellWidget(i, 0, lineEdit);
Then, in the editRow handler, retrieve the property by asking the QTableWidget for its focused child:
int row = m_table->currentRow();
if (row == -1) {
if (QWidget* focused = m_table->focusWidget()) {
row = focused->property("row").toInt();
}
}
The accepted solution, as is, would not work if rows might get deleted while the program runs. Thus the approach would require to update all the properties. Can be done, if this is a rare operation.
I got away with an iteration approach:
for(unsigned int i = 0; i < table->rowCount(); ++i)
{
if(table->cellWidget(i, relevantColumn) == QObject::sender())
{
return i;
}
}
return -1;
Quick, dirty, but worked, and in my case more suitable, as rows got deleted often or changed their positions, only buttons in the widget were connected to the slot and the slot was never called directly. If these conditions are not met, further checks might get necessary (if(QObject::sender()) { /* */ }, ...).
Karsten's answer will work correctly only if QLineEdit's property is recalculated each time a row is deleted, which might be a lot of work. And Aconcagua's answer works only if the method is invoked via signal/slot mechanism. In my solution, I just calculate the position of the QlineEdit which has focus (assuming all table items were set with setCellWidget):
int getCurrentRow() {
for (int i=0; i<myTable->rowCount(); i++)
for (int j=0; j<myTable->columnCount(); j++) {
if (myTable->cellWidget(i,j) == myTable->focusWidget()) {
return i;
}
}
return -1;
}

Qt C++ Get data from a selected row of a table view

I have a table view populated with data of Vehicle objects stored in a QList<Vehicle> cars; On this cars list i have to make some actions: search, add, edit, delete; After every action of search, i store the founded objects in another list to populate the table view only with this objects, keeping the original list intact. The original list gets modified only on add, edit or delete. Here comes the problem: i search for an object that i want to edit, it is shown in the table view, i select it and press the edit button; i am using QModelIndexList to get the index of the row. The index of the row will give me the position from the "founded" list, and i need to modify the object in the original list. Below is my implementation.
Is there any other way to this thing without the temporary list? How can i modify the original object using Iterator, instead that for loop?
void MainWindow::on_actionEdit_triggered()
{
QMessageBox msgBox;
QModelIndexList id = ui->tableView->selectionModel()->selectedIndexes();
if(id.isEmpty()){
msgBox.setWindowTitle("Message");
msgBox.setText("Please select a row");
msgBox.setDefaultButton(QMessageBox::Ok);
msgBox.exec();
} else{
int row = id.at(0).row();
QUuid carId = temp.at(row).getVehicleID(); // temp -> the "the founded" list
for(int i = 0; i < cars.size(); i++){
Vehicle& current = cars[i];
Vehicle& currentTemp = temp[row];
if(carId == current.getVehicleID() && carId == currentTemp.getVehicleID()){
addDialog = new AddEditDialog(this);
addDialog->loadVehicleToEdit(current);
addDialog->exec();
if(addDialog->getIsEdited()){
current = addDialog->getVehicleToAdd();
currentTemp = addDialog->getVehicleToAdd();
currentTemp.setVehicleId(carId);
current.setVehicleId(carId);
}
}
}
}
//create header
createHeader(model);
//set data to the table view
populate(temp);
}
May be you use proxy model and you need to call mapToSource?

Selected Rows in QTableView, copy to QClipboard

I have a SQLite-Database and I did it into a QSqlTableModel.
To show the Database, I put that Model into a QTableView.
Now I want to create a Method where the selected Rows (or the whole Line) will be copied into the QClipboard. After that I want to insert it into my OpenOffice.Calc-Document.
But I have no Idea what to do with the Selected SIGNAL and the QModelIndex and how to put this into the Clipboard.
To actually capture the selection you use the item view's selection model to get a list of indices. Given that you have a QTableView * called view you get the selection this way:
QAbstractItemModel * model = view->model();
QItemSelectionModel * selection = view->selectionModel();
QModelIndexList indexes = selection->selectedIndexes();
Then loop through the index list calling model->data(index) on each index. Convert the data to a string if it isn't already and concatenate each string together. Then you can use QClipboard.setText to paste the result to the clipboard. Note that, for Excel and Calc, each column is separated from the next by a newline ("\n") and each row is separated by a tab ("\t"). You have to check the indices to determine when you move to the next row.
QString selected_text;
// You need a pair of indexes to find the row changes
QModelIndex previous = indexes.first();
indexes.removeFirst();
foreach(const QModelIndex &current, indexes)
{
QVariant data = model->data(current);
QString text = data.toString();
// At this point `text` contains the text in one cell
selected_text.append(text);
// If you are at the start of the row the row number of the previous index
// isn't the same. Text is followed by a row separator, which is a newline.
if (current.row() != previous.row())
{
selected_text.append('\n');
}
// Otherwise it's the same row, so append a column separator, which is a tab.
else
{
selected_text.append('\t');
}
previous = current;
}
QApplication.clipboard().setText(selected_text);
Warning: I have not had a chance to try this code, but a PyQt equivalent works.
I had a similar problem and ended up adapting QTableWidget (which is an extension of QTableView) to add copy/paste functionality. Here is the code which builds on what was provided by quark above:
qtablewidgetwithcopypaste.h
// QTableWidget with support for copy and paste added
// Here copy and paste can copy/paste the entire grid of cells
#ifndef QTABLEWIDGETWITHCOPYPASTE_H
#define QTABLEWIDGETWITHCOPYPASTE_H
#include <QTableWidget>
#include <QKeyEvent>
#include <QWidget>
class QTableWidgetWithCopyPaste : public QTableWidget
{
Q_OBJECT
public:
QTableWidgetWithCopyPaste(int rows, int columns, QWidget *parent = 0) :
QTableWidget(rows, columns, parent)
{}
QTableWidgetWithCopyPaste(QWidget *parent = 0) :
QTableWidget(parent)
{}
private:
void copy();
void paste();
public slots:
void keyPressEvent(QKeyEvent * event);
};
#endif // QTABLEWIDGETWITHCOPYPASTE_H
qtablewidgetwithcopypaste.cpp
#include "qtablewidgetwithcopypaste.h"
#include <QApplication>
#include <QMessageBox>
#include <QClipboard>
#include <QMimeData>
void QTableWidgetWithCopyPaste::copy()
{
QItemSelectionModel * selection = selectionModel();
QModelIndexList indexes = selection->selectedIndexes();
if(indexes.size() < 1)
return;
// QModelIndex::operator < sorts first by row, then by column.
// this is what we need
// std::sort(indexes.begin(), indexes.end());
qSort(indexes);
// You need a pair of indexes to find the row changes
QModelIndex previous = indexes.first();
indexes.removeFirst();
QString selected_text_as_html;
QString selected_text;
selected_text_as_html.prepend("<html><style>br{mso-data-placement:same-cell;}</style><table><tr><td>");
QModelIndex current;
Q_FOREACH(current, indexes)
{
QVariant data = model()->data(previous);
QString text = data.toString();
selected_text.append(text);
text.replace("\n","<br>");
// At this point `text` contains the text in one cell
selected_text_as_html.append(text);
// If you are at the start of the row the row number of the previous index
// isn't the same. Text is followed by a row separator, which is a newline.
if (current.row() != previous.row())
{
selected_text_as_html.append("</td></tr><tr><td>");
selected_text.append(QLatin1Char('\n'));
}
// Otherwise it's the same row, so append a column separator, which is a tab.
else
{
selected_text_as_html.append("</td><td>");
selected_text.append(QLatin1Char('\t'));
}
previous = current;
}
// add last element
selected_text_as_html.append(model()->data(current).toString());
selected_text.append(model()->data(current).toString());
selected_text_as_html.append("</td></tr>");
QMimeData * md = new QMimeData;
md->setHtml(selected_text_as_html);
// qApp->clipboard()->setText(selected_text);
md->setText(selected_text);
qApp->clipboard()->setMimeData(md);
// selected_text.append(QLatin1Char('\n'));
// qApp->clipboard()->setText(selected_text);
}
void QTableWidgetWithCopyPaste::paste()
{
if(qApp->clipboard()->mimeData()->hasHtml())
{
// TODO, parse the html data
}
else
{
QString selected_text = qApp->clipboard()->text();
QStringList cells = selected_text.split(QRegExp(QLatin1String("\\n|\\t")));
while(!cells.empty() && cells.back().size() == 0)
{
cells.pop_back(); // strip empty trailing tokens
}
int rows = selected_text.count(QLatin1Char('\n'));
int cols = cells.size() / rows;
if(cells.size() % rows != 0)
{
// error, uneven number of columns, probably bad data
QMessageBox::critical(this, tr("Error"),
tr("Invalid clipboard data, unable to perform paste operation."));
return;
}
if(cols != columnCount())
{
// error, clipboard does not match current number of columns
QMessageBox::critical(this, tr("Error"),
tr("Invalid clipboard data, incorrect number of columns."));
return;
}
// don't clear the grid, we want to keep any existing headers
setRowCount(rows);
// setColumnCount(cols);
int cell = 0;
for(int row=0; row < rows; ++row)
{
for(int col=0; col < cols; ++col, ++cell)
{
QTableWidgetItem *newItem = new QTableWidgetItem(cells[cell]);
setItem(row, col, newItem);
}
}
}
}
void QTableWidgetWithCopyPaste::keyPressEvent(QKeyEvent * event)
{
if(event->matches(QKeySequence::Copy) )
{
copy();
}
else if(event->matches(QKeySequence::Paste) )
{
paste();
}
else
{
QTableWidget::keyPressEvent(event);
}
}
Quark's answer (the selected one) is good for pointing people in the right direction, but his algorithm is entirely incorrect. In addition to an off by one error and incorrect assignment, its not even syntactically correct. Below is a working version that I just wrote and tested.
Let's assume our example table looks like so:
A | B | C
D | E | F
The problem with Quark's algorithm is the following:
If we replace his \t separator with a ' | ', it will produce this output:
B | C | D
E | F |
The off by one error is that D appears in the first row. The incorrect assignment is evidenced by the omission of A
The following algorithm corrects these two problems with correct syntax.
QString clipboardString;
QModelIndexList selectedIndexes = view->selectionModel()->selectedIndexes();
for (int i = 0; i < selectedIndexes.count(); ++i)
{
QModelIndex current = selectedIndexes[i];
QString displayText = current.data(Qt::DisplayRole).toString();
// If there exists another column beyond this one.
if (i + 1 < selectedIndexes.count())
{
QModelIndex next = selectedIndexes[i+1];
// If the column is on different row, the clipboard should take note.
if (next.row() != current.row())
{
displayText.append("\n");
}
else
{
// Otherwise append a column separator.
displayText.append(" | ");
}
}
clipboardString.append(displayText);
}
QApplication::clipboard()->setText(clipboardString);
The reason I chose to use a counter instead of an iterator is just because it is easier to test if there exists another index by checking against the count. With an iterator, I suppose maybe you could just increment it and store it in a weak pointer to test if it is valid but just use a counter like I did above.
We need to check if the next line will be on on a new row. If we are on a new row and we check the previous row as Quark's algorithm does, its already too late to append. We could prepend, but then we have to keep track of the last string size. The above code will produce the following output from the example table:
A | B | C
D | E | F
For whatever reason I didn't have access to the std::sort function, however I did find that as a neat alternative to Corwin Joy's solution, the sort function can be implemented by replacing
std::sort(indexes.begin(), indexes.end());
with
qSort(indexes);
This is the same as writing:
qSort(indexes.begin(), indexes.end());
Thanks for your helpful code guys!
I wrote some code based on some of the others' answers. I subclassed QTableWidget and overrode keyPressEvent() to allow the user to copy the selected rows to the clipboard by typing Control-C.
void MyTableWidget::keyPressEvent(QKeyEvent* event) {
// If Ctrl-C typed
if (event->key() == Qt::Key_C && (event->modifiers() & Qt::ControlModifier))
{
QModelIndexList cells = selectedIndexes();
qSort(cells); // Necessary, otherwise they are in column order
QString text;
int currentRow = 0; // To determine when to insert newlines
foreach (const QModelIndex& cell, cells) {
if (text.length() == 0) {
// First item
} else if (cell.row() != currentRow) {
// New row
text += '\n';
} else {
// Next cell
text += '\t';
}
currentRow = cell.row();
text += cell.data().toString();
}
QApplication::clipboard()->setText(text);
}
}
Output example (tab-separated):
foo bar baz qux
bar baz qux foo
baz qux foo bar
qux foo bar baz
What you'll need to do is access the text data in the model, then pass that text to the QClipboard.
To access the text data in the model, use QModelIndex::data(). The default argument is Qt::DisplayRole, i.e. the displayed text.
Once you've retrieved the text, pass that text to the clipboard using QClipboard::setText().
a pyqt py2.x example:
selection = self.table.selectionModel() #self.table = QAbstractItemView
indexes = selection.selectedIndexes()
columns = indexes[-1].column() - indexes[0].column() + 1
rows = len(indexes) / columns
textTable = [[""] * columns for i in xrange(rows)]
for i, index in enumerate(indexes):
textTable[i % rows][i / rows] = unicode(self.model.data(index).toString()) #self.model = QAbstractItemModel
return "\n".join(("\t".join(i) for i in textTable))
I finally got it, thanks.
void Widget::copy() {
QItemSelectionModel *selectionM = tableView->selectionModel();
QModelIndexList selectionL = selectionM->selectedIndexes();
selectionL.takeFirst(); // ID, not necessary
QString *selectionS = new QString(model->data(selectionL.takeFirst()).toString());
selectionS->append(", ");
selectionS->append(model->data(selectionL.takeFirst()).toString());
selectionS->append(", ");
selectionS->append(model->data(selectionL.takeFirst()).toString());
selectionS->append(", ");
selectionS->append(model->data(selectionL.takeFirst()).toString());
clipboard->setText(*selectionS);
}
and
connect (tableView, SIGNAL(clicked(QModelIndex)), this, SLOT(copy()));
I can't help but notice that you can simplify your code using a foreach() construct and the QStringList class, which has a convenient join() function.
void Widget::copy()
{
QStringList list ;
foreach ( const QModelIndex& index, tableView->selectedIndexes() )
{
list << index.data() ;
}
clipboard->setText( list.join( ", " ) ) ;
}
Careful with the last element. Note below, indexes may become empty after 'removeFirst()'. Thus, 'current' is never valid and should not be used in model()->data(current).
indexes.removeFirst();
QString selected_text;
QModelIndex current;
Q_FOREACH(current, indexes)
{
.
.
.
}
// add last element
selected_text.append(model()->data(current).toString());
Consider
QModelIndex last = indexes.last();
indexes.removeFirst();
QString selected_text;
Q_FOREACH(QModelIndex current, indexes)
{
.
.
.
}
// add last element
selected_text.append(model()->data(last).toString());
Here is a variation on what Corwin Joy posted that works with QTableView and handles sparse selections differently. With this code if you have different columns selected in different rows (e.g. selected cells are (1,1), (1, 2), (2, 1), (3,2)) then when you paste it you will get empty cells corresponding to the "holes" in your selection (e.g. cells (2,2) and (3,1)). It also pulls in the column header text for columns that intersect the selection.
void CopyableTableView::copy()
{
QItemSelectionModel *selection = selectionModel();
QModelIndexList indices = selection->selectedIndexes();
if(indices.isEmpty())
return;
QMap<int, bool> selectedColumnsMap;
foreach (QModelIndex current, indices) {
selectedColumnsMap[current.column()] = true;
}
QList<int> selectedColumns = selectedColumnsMap.uniqueKeys();
int minCol = selectedColumns.first();
// prepend headers for selected columns
QString selectedText;
foreach (int column, selectedColumns) {
selectedText += model()->headerData(column, Qt::Horizontal, Qt::DisplayRole).toString();
if (column != selectedColumns.last())
selectedText += QLatin1Char('\t');
}
selectedText += QLatin1Char('\n');
// QModelIndex::operator < sorts first by row, then by column.
// this is what we need
qSort(indices);
int lastRow = indices.first().row();
int lastColumn = minCol;
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 += model()->data(current).toString();
}
selectedText += QLatin1Char('\n');
QApplication::clipboard()->setText(selectedText);
}
If anybody is interested, this web page provide a working code project on this topic, it's working pretty well.
Copy / paste functionality implementation for QAbstractTableModel / QTableView