DelegateChooser not working with TableView and QStandardItemModel

Bartelchen

i have a QStandardItemModel which I fill by receiving a JSON. The JSON looks sth like this:

{
   "vehicle_list": [
       "subs": [ "CAM_1", "CAM_2",  ... ],
       "name": "vehicle_0"
    ]
}

I put this into a QStandardItemModel. Each row reprents one Vehicle, and the column entrys are the Name, and after that the cameras:

ROW(0): vehicle_0, cam_1, cam_2, ...
ROW(1): vehicle_1, cam_1, cam_2, ...

This works as intended. So I want to display the data in my model with an TableView in QML. And i need to display the vehicle name as a text, and the cameras as buttons. My QML file looks like this:

TableView {
    id: vehicleView
    model: vehicleModel
    anchors.fill: parent
    delegate: myChooser

    DelegateChooser {
        id: myChooser
        role: "r_vehicle_type"

        DelegateChoice {
            id: choice1
            roleValue: "camera"
            delegate: Rectangle {
                width: 100
                height: 30
                border.color: "black"
                border.width: 1

                Component.onCompleted: {
                    console.log("Camera: col=", choice1.column, ", row=", choice1.row)
                }

                Button {
                    text: r_camera_name
                }
            }
        }

        DelegateChoice {
            roleValue: "vehicle"
            delegate: Rectangle {
                width: 100
                height: 30
                border.color: "black"
                border.width: 1

                Text {
                    text: r_vehicle_name
                }
            }
        }
    }
}

If I run my app like this, the console puts out the following:

TableView: failed loading index: 0
TableView: failed loading index: 1
TableView: failed loading index: 2
TableView: failed loading index: 3
TableView: failed loading index: 4
TableView: failed loading index: 5
TableView: failed loading index: 6

If I dont use the DelegateChooser but instead something like:

delegate: Rectangle {
width: 100
height: 20
Text {
 text: r_vehicle_name
 }
}

(with r_vehicle_name is the role defined in my model, where i put the vehicle name) works fine.

Anyone got a helping hand?

Thanks in advance,
Bartelchen

Bartelchen

I managed to (partially) solve the issue . I was missing a default DelegateChoice, therefor the indexes could not be loaded ... which leads me to my next problem:

The default option is always chosen by my DelgateChooser for the first column. The type for the first column should always be "vehicle" and I set it in my model like the following:

for(int i = 0; i < m_model->rowCount(); i++) {
        for(int j = 0; j < m_model->columnCount(); j++) {
            qDebug() << i << j;
            if(j==0) {
                m_model->setData(m_model->index(i, j), jValueNameList.at(i).toString(), Vehicle::VEHICLE_NAME);
                m_model->setData(m_model->index(i, j), "vehicle", Vehicle::TYPE);
            } else {
                m_model->setData(m_model->index(i, j), jArraySubsList.at(i).at(j-1), Vehicle::CAMERA_NAME);
                m_model->setData(m_model->index(i, j), "camera", Vehicle::TYPE);
            }
}

The DelegateChooser with the default option looks like this:

DelegateChooser {
id: myChooser
role: "r_vehicle_type"

    DelegateChoice {
        roleValue: "vehicle"
        Rectangle {
            width: 100
            height: 30
            border.color: "blue"
            border.width: 1
            Text {
                text:  model.r_vehicle_name
            }
        }
    }
    DelegateChoice {
        roleValue: "camera"
        Rectangle {
            width: 100
            height: 30
            border.color: "green"
            border.width: 1
            Text {
                text: model.r_vehicle_cam
            }
        }
    }
    DelegateChoice {
        Rectangle {
            width: 100
            height: 30
            border.color: "red"
            border.width: 1
            Text {
                text: "default"
            }
        }
    }

}
```

Every entry with "camera" as type is displayed correctly. Any ideas what I am missing now? I know that I could just use the "default" choice for the vehicle type, but I want to know why my type "vehicle" is not processed correctly.

Greetings

Bartelchen

Another update on this topic ... and I am even more confused:

I just started testing the reception of multiple vehicle in my JSON message so my model consists of multiple rows.

The index (0, 0 -- first row, first entry) still gets displayed incorrectly, being displayed by the "default" delegateChoice.
For every row following, the index (X, 0) is getting displayed correctly by the delegateChoice with roleValue "vehicle".

I debugged the model data after inserting into the first column. I get the following output:

First Column, type:  QVariant(QString, "vehicle")
First Column, type:  QVariant(QString, "vehicle")
First Column, type:  QVariant(QString, "vehicle")

Why is just the first index not displayed correctly?

Pavel Kovalenko

@Bartelchen
I had same problem.
I noticed with qdebug that when I move ScrollIndicator - DelegateChooser roleValue was updated from model[0,0] and after that everything is ok. So my solution was to add this to TableView:

Component.onCompleted: {
    model.invalidate();
}

strahlex

I'm seeing the same thing here as well. Has anyone reported it as bug?