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QAbstractItemModel item identification from ModelIndex

  • Hi!

    I need a QTreeView with a model referring to existing data(using C++).

    The data is a tree, using raw pointers in its nodes. I can reach any node by a custom unique ID.

    If I understand the paradigm correctly, my model have to implement functions like 'parent' in which I need to tell the parent item's ModelIndex from the ModelIndex of the child. I can do this by storing the data tree pointers in ModelIndex. This can be unsafe in my case. Is there any other option to handle this correctly?

  • Lifetime Qt Champion

    HI and welcome to devnet,

    Why is it unsafe in your case ?

    Did you already saw the Simple Tree Model example in Qt's documentation ?

  • Hi! Thanks for the answer

    I think it is unsafe beacause my data tree can change by other mechanisms.
    I don't think that keeping pointers to dynamically changing data is a good idea in general.

    I've tried it( because I had no better idea) and now I have some new problem. I will post them to another topic.

  • Lifetime Qt Champion

    Then you have to propagate the information when your underlying data changes.

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