What C++ types correspond to QML types?
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To what C++ types do the following QML types correspond? In other words, what are the appropriate C++ method parameters types or return types? Should C++ values, references or pointers be used?
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{"Key1": "Value1", "Key2": "Value2"}
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{Key1: "Value1", Key2: "Value2"}
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["Value1", "Value2"]
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[{"Key1": "Value1", "Key2": "Value2"}, {"Key3": "Value3", "Key4": "Value4"}]
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[["Value1", "Value2"], ["Value3", "Value4"]]
@etc.
Is there any documentation or examples of this?
In addition, when are QStringList, QList, QLinkedList, QMap, etc. used? When are C++ (i.e., non-Qt) collection classes used like those in STL?
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Hi,
See "Interacting with QML Objects from C++":http://qt-project.org/doc/qt-5/qtqml-cppintegration-interactqmlfromcpp.html -- Data is passed between C++ and QML using QVariant, and it is passed by-value (no pointers or references).
These pages might be of interest to you too:
- "Data Type Conversion Between QML and C++":http://qt-project.org/doc/qt-5/qtqml-cppintegration-data.html
- "Performance Considerations And Suggestions|Type Conversion":http://qt-project.org/doc/qt-5/qtquick-performance.html#type-conversion
[quote author="SteveG" date="1403299415"]In addition, when are QStringList, QList, QLinkedList, QMap, etc. used? When are C++ (i.e., non-Qt) collection classes used like those in STL? [/quote]QML uses JavaScript types. In the examples you gave, curly braces represent JavaScript objects (stored as QMap) and square braces represent JavaScript arrays (stored as QList).
Note: QStringList is simply a typedef of QList<QString>.
Qt uses Qt containers, not STL containers. Also, I don't think QLinkedList is used in QML.
