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    • UNSOLVED ListView won't get updated when I change data in my custom model
      General and Desktop • listview listmodel data models models • • ivarec  

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      Can we finally see where and how you emit dataChanged()? And with which indexes?
    • SOLVED Save data from multiple Qt components scattered around multiple QML files
      QML and Qt Quick • qml design data models scope model binding • • ivarec  

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      I went with the Binding solution in the end :)
    • UNSOLVED Conversion of a SQL model into a standard item model?
      General and Desktop • qsqltablemodel qstandarditemmo data models software design proxies • • elfring  

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      I don't understand this question. How do you think about information from Cppcheck's forum and issue tracker? Do you care for software aspects which can be discussed there?
    • UNSOLVED Increasing usage for C++ new operators based on data model indexes?
      General and Desktop • data models software design createindex allocation new operators • • elfring  

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      Of course I'll cast my -1 vote as well. I'll add to point 1: If the data contained in the model is all of basic types or implicitly shared types then it's possible to already use the current framework without ever triggering any expensive* copy , to point 2: There's no clarity on how to support different types in different roles would we need an additional template argument for each used role beyond Qt::UserRole? is so the problems above grow exponentially with the roles And to point 3: No possible implementation for a reliable dataChanged emission if model internals are exposed directly *expensive = a copy that implies more that a: memcpy of less than 65bits and an increase/decrease of a numeric reference counter
    • UNSOLVED Support for multi-index containers?
      General and Desktop • data models keys software design containers multi-index • • elfring  

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      @elfring said in Support for multi-index containers?: Would you like to distinguish any more between the usage of one- and two-dimensional structures for data models? Nope, the 2 dimensional structure is strictly more general of the 1D version so anything that goes for the first works in the second case. beginRant(); You have been discussing a lot of theoretical problems relating to models across different threads. In all of them the feeling has been that you are uselessly overcomplicating things. I feel it would be useful for you and easier for us to walk you through a concrete example of what you are trying to achieve rather than discuss endlessly on theoretical concepts. endRant();
    • UNSOLVED Software development challenges around index creation for data models
      General and Desktop • data models software design integers algorithms index creation • • elfring  

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      @elfring said in Software development challenges around index creation for data models: Will your data source work without hierarchies then? I don't follow. This is a table model, there's no hierarchy here.
    • UNSOLVED Supporting data models for file lists
      General and Desktop • data models software design qfileinfo file management file lists • • elfring  

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      Hi, QAbstractListModel
    • UNSOLVED Extending data models with fields
      General and Desktop • data models proxy software design classes fields • • elfring  

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      That I don't know. If you have an interesting re-usable model to share then you can do a submission.
    • UNSOLVED Increasing usage of references for non-value objects?
      General and Desktop • data models software design references value objects copying • • elfring  

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      Imagine these methods become available in a future version of Qt: I suggest to take another look for a clarification try around the topic “Checking the API status for the variable “Private d” of the QVariant class”.
    • UNSOLVED Support for QStandardItem proxies?
      General and Desktop • qstandarditem data models proxy custom data adapter • • elfring  

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      @Christian-Ehrlicher said in Support for QStandardItem proxies?: But only when Qt was compiled in debug mode Yes, as the docs say using invalid indexes remains undefined behaviour, I am just trying to help users spot these cases
    • UNSOLVED Presentation for custom data types by views
      General and Desktop • qvariant qstandarditem data models custom data presentation • • elfring  

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      Unless you go into very specific obscure cases Another software design possibility would be to fiddle with proxies for data models (and their items), wouldn't it?
    • UNSOLVED Support for constructing QStandardItem objects from QVariant references?
      General and Desktop • qvariant qstandarditem data models custom data construction • • elfring  

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      @elfring said in Support for constructing QStandardItem objects from QVariant references?: I would appreciate if I can reuse existing functionality from a higher level base class. Sorry! I just re-read this line and realized you said "higher level base class". In this case, please ignore what I said about choosing pros and cons.
    • UNSOLVED Triggering common actions for a data model from a view
      General and Desktop • qstandarditemmo serialization data models views • • elfring  

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      If you mean outside of answering question here in forum, then no thank you. :) I am curious then if you would like to clarify related development topics. Do you know any higher level tools which can display structural differences between standard item models in a clear way? Have you got any experiences with “diff views” in this software area?