Combobox in Qtableview

[VRonin]

https://forum.qt.io/topic/125906/qtableview-combobox-in-columns

[n-2204]

this is using delegate approach

[artwaw]

@n-2204 and that's how it should be done.

[n-2204]

but i shared the code and i am asking doubt in that
thanks

[VRonin]

Your approach is wrong

If you still want to use it, as in your other questions, you have to connect a slot to the rowsInserted signal

[n-2204]

thanks
thats what i am asking like which slot need to need or what i m missing

[n-2204]

using this rowinserted signal even not going on this slot

connect(ui.tableView->model(), SIGNAL(rowsInserted), ui.tableView_2->model(), SLOT(changedvalue()));

void tool::changedvalue()
{
QAbstractItemModel* table1 = ui.tableView->model();
QAbstractItemModel* table2 = ui.tableView_2->model();
for (int i = 0, maxI = table2->rowCount();i <= maxI;++i)//combobox in table2 col1
{
    for (int r = 0, maxI = table1->rowCount();r < maxI;++r)//getvalue fromtable1
    {
        QComboBox* combo = new QComboBox();
        QString list1[10] = { table1->data(table1->index(r, 0)).toString() };//store value in list
        qDebug() << "combox values1" ;
        for (int j = 0; j < 10; j++)
        {
              combo->addItem(list1[j]);/pass list to combobox
            qDebug() << "combox values" << list1[j];/
        }
        ui.tableView_2->setIndexWidget(ui.tableView_2->model()->index(i, 1), combo);
    }      
}
}

[Christian Ehrlicher]

@n-2204 said in Combobox in Qtableview:

connect(ui.tableView->model(), SIGNAL(rowsInserted), ui.tableView_2->model(), SLOT(changedvalue()));

This is wrong - again: use the new signal/slot syntax to catch such errors on compile time. And if you don't want then watch the output to stdout during debugging!

[JonB]

@Christian-Ehrlicher
I, and you, have repeatedly advised @n-2204 to change from the old macros to the new style, and provided the necessary links (e.g. https://forum.qt.io/topic/126193/spinbox-input-add-rows, I think we posted 4 times there to this effect). Precisely because the user keeps getting the connections wrong. It seems the user is not interested in making the effort to change their ways, and prefers to make the same mistakes and keep posting for others to sort out....

[n-2204]

connect(ui.tableView->model(), &QAbstractItemModel::rowsInserted, this,
&tool::changedvalue);

but signal/slot should work for both the ways
and one thing is there is change in column 1 row values and @VRonin you told to use signal rowinserted() ?

[VRonin]

but signal/slot should work for both the ways

It does but in case you make a mistake the new syntax lets you know straight away when you try to compile and it's not just a warning in the console while the program runs.
Also the new connection is faster

there is change in column 1 row values and @VRonin you told to use signal rowinserted() ?

In that case you would use the conveniently named dataChanged signal

void tool::changedvalue()

please do no rebuild all the widgets everytime something changes. setIndexWidget is already super inefficient, if you keep recreating them your program will probably stutter a lot

[n-2204]

So when i am passing my values in a Qstring that time its coming in combobox but same when i try using table1 column1 rows value that time only last row value is adding in Combobox values looks like all values not appending
Where need to make changes?

connect(ui.tableView->model(), &QAbstractItemModel::dataChanged, this,
          &Gearcycle_model::changedvalue);

void tool::changedvalue() {
QAbstractItemModel* table1 = ui.tableView->model();
QAbstractItemModel* table2 = ui.tableView_2->model();
for (int i = 0, maxI = table2->rowCount();i <= maxI;++i)//combobox in table2 col1
{
    for (int r = 0, maxI = table1->rowCount();r < maxI;++r)//getvalue fromtable1
    {
        QComboBox* combo = new QComboBox();
        //QString list1[10] = { table1->data(table1->index(r, 0)).toString() };//store value in list
        QString list1[4] = { "input 1","input 2","input3","input 4" };
        qDebug() << "table index" << r;
        for (int j = 0; j < 3; j++)
        {
            combo->addItem(list1[j]);
            qDebug() << "combox values" << list1[j];//pass list to combobox
            qDebug() << "list j=" << j;
        }
        ui.tableView_2->setIndexWidget(ui.tableView_2->model()->index(i, 1), combo);
        qDebug() << "row value i=" << i;
    }
}
}

[VRonin]

@n-2204 said in Combobox in Qtableview:

Where need to make changes?

Read your code. The loops are wrong, this is basic C++

[n-2204]

@n-2204 said in Combobox in Qtableview:

So when i am passing my values in a Qstring that time its coming in combobox but same when i try using table1 column1 rows value that time only last row value is adding in Combobox values looks like all values not appending
Where need to make changes?

connect(ui.tableView->model(), &QAbstractItemModel::dataChanged, this,
          &Gearcycle_model::changedvalue);

void tool::changedvalue() {
QAbstractItemModel* table1 = ui.tableView->model();
QAbstractItemModel* table2 = ui.tableView_2->model();
for (int i = 0, maxI = table2->rowCount();i <= maxI;++i)//combobox in table2 col1
{
    for (int r = 0, maxI = table1->rowCount();r < maxI;++r)//getvalue fromtable1
    {
        QComboBox* combo = new QComboBox();
        //QString list1[10] = { table1->data(table1->index(r, 0)).toString() };//store value in list

when passing this that time only last row value is coming in combobox

        QString list1[4] = { "input 1","input 2","input3","input 4" };

this is working when i am passing QString list1[4] = { "input 1","input 2","input3","input 4" }; in combobox

        for (int j = 0; j < 3; j++)
        {
            combo->addItem(list1[j]);
            qDebug() << "combox values" << list1[j];//pass list to combobox
            qDebug() << "list j=" << j;
        }
        ui.tableView_2->setIndexWidget(ui.tableView_2->model()->index(i, 1), combo);
        qDebug() << "row value i=" << i;
    }
}
}

yes, looks like some small change will be needed during addItem in combobox

[VRonin]

Look at the loops of i and r. think about what they are doing, ask yourself when you want to create and populate a combo, inside which loop?

[n-2204]

ya it works thankyou.

void tool::rowvalue1() {
QAbstractItemModel* table1 = ui.tableView->model();
QAbstractItemModel* table2 = ui.tableView_2->model();
for (int i = 0, maxI = table2->rowCount();i < maxI;++i)//combobox in table2 col1
{
     QComboBox* combo = new QComboBox();
      combo->setDuplicatesEnabled(false);
  for (int r = 0, maxI = table1->rowCount();r < maxI;++r)//getvalue fromtable1
      {
         QString list1[10] = { table1->data(table1->index(r, 0)).toString() };//store value in list
       for (int j = 0; j < 1; ++j)
        {

--using uniqueSet trying to add only unique values(no duplicate values) in Combobox but its not working is this correct way ? or any other way to do this ?

            QSet<QString> uniqueSet;
             if (!uniqueSet.contains(list1[j]))//add only unique values in combobox
             {
                uniqueSet.insert(list1[j]);
                combo->addItem(list1[j]);  //add list to combobox  
                qDebug() << " values " << list1[j];
            }
        }
        ui.tableView_2->setIndexWidget(table2->index(i, 1), combo);
    }
  }
}

[VRonin]

@n-2204 said in Combobox in Qtableview:

for (int j = 0; j < 1; ++j)

[n-2204]

no its 10
j<10
using uniqueSet trying to add only unique values(no duplicate values) in Combobox but its not working is this correct way ? or any other way to do this ?

[VRonin]

My feeling is that you have no idea what your code does, you are just copy-pasting stuff around and hoping that it does something.
Once again: read your code, run it step-by-step. This has nothing to do with Qt, it's just about loops

[n-2204]

thanks for your answers

but what i shared i working code
and now i asked -
using uniqueSet trying to add only unique values(no duplicate values) in Combobox but this way not working is this correct way ? or any other way to do this ?

this it might be very simple for you or you are expert but i am new C++ and Qt so i am having so many doubts may be silly.
Thanks