tableWidget question

[JonB]

@jenya7
You can only do that once the row, row_num, exists in the table. You will need to have called https://doc.qt.io/qt-5/qtablewidget.html#insertRow to insert the row(s) beforehand.

[mrjj]

Hi
This might come in handy
https://wiki.qt.io/How_to_Use_QTableWidget

[jenya7]

@mrjj said in tableWidget question:

Hi
This might come in handy
https://wiki.qt.io/How_to_Use_QTableWidget

Thank you. One more question - after populating the table - how can I check/uncheck a check box in a row or to check a check box state?

[mrjj]

@jenya7
Hi
There is https://doc.qt.io/qt-5/qtablewidget.html#item
where you can access the items to check or uncheck it.

But often you use some of the signals
like
https://doc.qt.io/qt-5/qtablewidget.html#itemChanged
and there you directly get the item.

[jenya7]

@mrjj said in tableWidget question:

@jenya7
Hi
There is https://doc.qt.io/qt-5/qtablewidget.html#item
where you can access the items to check or uncheck it.

But often you use some of the signals
like
https://doc.qt.io/qt-5/qtablewidget.html#itemChanged
and there you directly get the item.

Thank you.

[jenya7]

I did so

void sys::ParamLoadToTable(QTableWidget *table, int rows)
{

    QTableWidgetItem item;

    table->setRowCount(rows);

    for (int i = 0; i < rows; i++)
    {
        auto box = new QCheckBox();
        box->setCheckState(Qt::Unchecked);

        table->setCellWidget(i, 3, box);

        item.setText(param_list[i].name);
        table->setItem(i, 1, &item);
    }
}

I see all rows but column 1 (name) is empty.

[jenya7]

OK. This way it works

for (int i = 0; i < rows; i++)
    {
        auto box = new QCheckBox();
        box->setCheckState(Qt::Unchecked);

        table->setCellWidget(i, 3, box);

         QTableWidgetItem  * item1 = new QTableWidgetItem();
         table->setItem(i, 1, item1);
       
         QTableWidgetItem  * item2 = new QTableWidgetItem();
          table->setItem(i, 2, item2);

        item1->setText(param_list[i].name);
        item2->setText(param_list[i].value);
    }

[jenya7]

How can I check if a check box in the 4-th column is set?

[mrjj]

@jenya7
Hi
You can use
https://doc.qt.io/qt-5/qtablewidget.html#cellWidget
to gain access to the checkbox.

[jenya7]

@mrjj said in tableWidget question:

@jenya7
Hi
You can use
https://doc.qt.io/qt-5/qtablewidget.html#cellWidget
to gain access to the checkbox.

 QWidget *box = table->cellWidget(i, 3);

Then what? How do I get the check box state from the object?

[Christian Ehrlicher]

@jenya7 said in tableWidget question:

How do I get the check box state from the object?

Try to cast it to a QCheckBox (with e.g. dynamic_cast or Qt's specific qobject_cast) and retrieve the information.

[mrjj]

@jenya7
Hi
It returns a base Widget pointer so you need to cast it.

QCheckBox * checkbox = qobject_cast<QCheckBox * > (table->cellWidget(i, 3)) ;
if (checkbox) { // must check. can be NULL
if ( checkbox->isChecked() ) ....
}

[jenya7]

@mrjj said in tableWidget question:

@jenya7
Hi
It returns a base Widget pointer so you need to cast it.

QCheckBox * checkbox = qobject_cast<QCheckBox * > (table->cellWidget(i, 3)) ;
if (checkbox) { // must check. can be NULL
if ( checkbox->isChecked() ) ....
}

Thank you.

[VRonin]

@JonB said in tableWidget question:

you might be tempted to use https://doc.qt.io/qt-5/qabstractitemview.html#setIndexWidget, you will have @VRonin descending on you like a ton of bricks here if you do so

And here I am!

Also QCheckBox is the worst excuse to use this method. It's much easier to do without a widget.

To activate a checkbox in a cell you can just call:

QTableWidgetItem  *checkBoxitem = new QTableWidgetItem;
checkBoxitem->setCheckState(Qt::Unchecked); // displays the checkbox as unchecked
checkBoxitem->setFlags(checkBoxitem->flags() | Qt::ItemIsUserCheckable); // allows the user to click on the checkbox
table->setItem(i, 3, checkBoxitem);

You can then check the item state using item->checkState() or widget->model()->index(row,column).data(Qt::CheckStateRole)