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QMetaType Class Reference
^{[QtCore module]}

The QMetaType class manages named types in the meta-object system. More...

Types

• enum Type { Void, Bool, Int, UInt, ..., User }

Methods

• __init__ (self)
• __init__ (self, QMetaType)

Static Methods

• bool isRegistered (int)
• int type (str)
• str typeName (int)

The class is used as a helper to marshall types in QVariant and in queued signals and slots connections. It associates a type name to a type so that it can be created and destructed dynamically at run-time. Declare new types with Q_DECLARE_METATYPE() to make them available to QVariant and other template-based functions. Call qRegisterMetaType() to make type available to non-template based functions, such as the queued signal and slot connections.

Any class or struct that has a public default constructor, a public copy constructor, and a public destructor can be registered.

The following code allocates and destructs an instance of MyClass:

 int id = QMetaType.type("MyClass");
 if (id == 0) {
     void *myClassPtr = QMetaType.construct(id);
     ...
     QMetaType.destroy(id, myClassPtr);
     myClassPtr = 0;
 }

If we want the stream operators operator<<() and operator>>() to work on QVariant objects that store custom types, the custom type must provide operator<<() and operator>>() operators.

See also Q_DECLARE_METATYPE(), QVariant.setValue(), QVariant.value(), and QVariant.fromValue().

Type Documentation

QMetaType.Type

These are the built-in types supported by QMetaType:

Additional types can be registered using Q_DECLARE_METATYPE().

See also type() and typeName().

Method Documentation

QMetaType.__init__ (self)

QMetaType.__init__ (self, QMetaType)

bool QMetaType.isRegistered (int)

Returns true if the datatype with ID type is registered; otherwise returns false.

See also type(), typeName(), and Type.

int QMetaType.type (str)

Returns a handle to the type called typeName, or 0 if there is no such type.

See also isRegistered(), typeName(), and Type.

str QMetaType.typeName (int)

Returns the type name associated with the given type, or 0 if no matching type was found. The returned pointer must not be deleted.

See also type(), isRegistered(), and Type.