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Changing single properties of children without knowing id

  • Hi,

    I have a general question, motivated by my problem in https://forum.qt.io/topic/103394/using-subscripts-in-text-inside-combobox

    If I use e.g. a ComboBox can I change a property in the combobox's contentItem (e.g. setting textFormat = Text.RichtText) without replacing the complete contentItem? The problem is, that contentItem does not have an id which I can sue.

  • Moderators

    You don't need an ID as long as you do have it's parent ID. Assuming that:

    SomeItem {
      id: bob
      contentItem: Text {
        textFormat: Text.RichText

    You should be able to do:

    // Some JS function
    bob.contentItem.textFormat = Text.PlainText

    In your case, you are attempting to modify an already displayed delegate, right? That is wrong, don't do it. Delegates are created and deleted on the fly, you should not relay on them in any way. If you need to modify the data or the way it is displayed, you should use your model for that, thus exposing data to your delegate so that it can adapt to it.

  • Yes, I am attempting to modify an already displayed delegate, setting the textFormat for a ComboBox or CheckBox. I thought if I do it in Component.onCompleted it would be OK, or not?

    Edit: I just tried your suggestion for a ComboBox, and it works perfectly, doing it insideComponent.onCompleted.

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