How do you specify values for a ComboBox?

kitfox

I have a combo box that looks like

                ComboBox {
                    id: gridCombo

                    model: ListModel {
                        id: gridModel
                        ListElement {
                            text: "1/1"
                        }
                        ListElement {
                            text: "1/2"
                        }
                        ListElement {
                            text: "1/4"
                        }
                        ListElement {
                            text: "1/8"
                        }
                    }
                }

I would like to associate integers with each label equal to the denominator of each label. Is there a way to do this? If I try adding a 'value' field, the combo box displays blank entries.

I've also tried this alternate syntax, but it also displays blanks:

                ComboBox {
                    id: gridCombo
                    model: [
                        { text: firstValue, value: firstValue },
                        { text: secondValue, value: secondValue },
                        { text: thirdValue, value: thirdValue }
                    ]
                }

KroMignon

@kitfox said in How do you specify values for a ComboBox?:

Yes I have. It didn't help. Like I said in my post, the second form isn't displaying anything.

Then you don't have read it carefully, you have to define textRole and valueRole, cf https://doc.qt.io/qt-5/qml-qtquick-controls2-combobox.html#combobox-model-roles:

ComboBox {
    textRole: "text"
    valueRole: "value"
    id: gridCombo
    model: [
        { text: firstValue, value: firstValue },
        { text: secondValue, value: secondValue },
        { text: thirdValue, value: thirdValue }
    ]
}

Markkyboy

Have you read the documentation for ComboBox QML?; https://doc.qt.io/qt-5/qml-qtquick-controls2-combobox.html

kitfox

Yes I have. It didn't help. Like I said in my post, the second form isn't displaying anything.

jeremy_k

@kitfox said in How do you specify values for a ComboBox?:

I've also tried this alternate syntax, but it also displays blanks:

                ComboBox {
                    id: gridCombo
                    model: [
                        { text: firstValue, value: firstValue },
                        { text: secondValue, value: secondValue },
                        { text: thirdValue, value: thirdValue }
                    ]
                }

According to the documentation:

When using models that have multiple named roles, ComboBox must be configured to use a specific text role for its display text and delegate instances. If you want to use a role of the model item that corresponds to the text role, set valueRole. The currentValue property and indexOfValue() method can then be used to get information about those values.

Unless textRole and valueRole are set, the ComboBox doesn't know which role to use for each purpose.

KroMignon

@kitfox said in How do you specify values for a ComboBox?:

Yes I have. It didn't help. Like I said in my post, the second form isn't displaying anything.

Then you don't have read it carefully, you have to define textRole and valueRole, cf https://doc.qt.io/qt-5/qml-qtquick-controls2-combobox.html#combobox-model-roles:

ComboBox {
    textRole: "text"
    valueRole: "value"
    id: gridCombo
    model: [
        { text: firstValue, value: firstValue },
        { text: secondValue, value: secondValue },
        { text: thirdValue, value: thirdValue }
    ]
}