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+.. currentmodule:: PySide6.QtCore
+.. py:class:: Property
+
+Detailed Description
+--------------------
+
+The Property function lets you declare properties that
+behave both as Qt and Python properties, and have their
+getters and setters defined as Python functions.
+
+They are equivalent to the ``Q_PROPERTY`` macro in the `Qt Docs`_.
+
+Here is an example that illustrates how to use this
+function:
+
+.. code-block:: python
+ :linenos:
+
+ from PySide6.QtCore import QObject, Property
+
+ class MyObject(QObject):
+ def __init__(self, startval=42):
+ QObject.__init__(self)
+ self.ppval = startval
+
+ def readPP(self):
+ return self.ppval
+
+ def setPP(self, val):
+ self.ppval = val
+
+ pp = Property(int, readPP, setPP)
+
+ obj = MyObject()
+ obj.pp = 47
+ print(obj.pp)
+
+The full options for ``QtCore.Property`` can be found with ``QtCore.Property.__doc__``:
+
+.. code-block:: python
+
+ Property(self, type: type,
+ fget: Optional[Callable] = None,
+ fset: Optional[Callable] = None,
+ freset: Optional[Callable] = None,
+ fdel: Optional[Callable] = None,
+ doc: str = '',
+ notify: Optional[Callable] = None,
+ designable: bool = True,
+ scriptable: bool = True,
+ stored: bool = True, user: bool = False,
+ constant: bool = False,
+ final: bool = False) -> PySide6.QtCore.Property
+
+Normally, only ``type``, ``fget``and ``fset`` are used.
+
+
+Properties compared with Python properties
+------------------------------------------
+
+``Python`` has property objects very similar to ``QtCore.Property``.
+Despite the fact that the latter has an extra ``freset`` function, the usage
+of properties is almost the same. The main difference is that ``QtCore.Property``
+requires a ``type`` parameter.
+
+In the above example, the following lines would be equivalent properties:
+
+.. code-block:: python
+
+ pp = QtCore.Property(int, readPP, setPP) # PySide version
+ pp = property(readPP, setPP) # Python version
+
+As you know from the `Python Docs`_, ``Python`` allows to break the property
+creation into multiple steps, using the decorator syntax. We can do this in
+``PySide`` as well:
+
+.. code-block:: python
+ :linenos:
+
+ from PySide6.QtCore import QObject, Property
+
+ class MyObject(QObject):
+ def __init__(self, startval=42):
+ QObject.__init__(self)
+ self.ppval = startval
+
+ @Property(int)
+ def pp(self):
+ return self.ppval
+
+ @pp.setter
+ def pp(self, val):
+ self.ppval = val
+
+ obj = MyObject()
+ obj.pp = 47
+ print(obj.pp)
+
+Please be careful here: The two ``Python`` functions have the same name, intentionally.
+This is needed to let ``Python`` know that these functions belong to the same property.
+
+
+Properties in QML expressions
+-----------------------------
+
+If you are using properties of your objects in QML expressions,
+QML requires that the property changes are notified. Here is an
+example illustrating how to do this:
+
+.. code-block:: python
+ :linenos:
+
+ from PySide6.QtCore import QObject, Signal, Property
+
+ class Person(QObject):
+
+ name_changed = Signal()
+
+ def __init__(self, name):
+ QObject.__init__(self)
+ self._person_name = name
+
+ def _name(self):
+ return self._person_name
+
+ name = Property(str, _name, notify=name_changed)
+
+.. _`Python Docs`: https://docs.python.org/3/library/functions.html?highlight=property#property
+.. _`Qt Docs`: https://doc.qt.io/qt-6/properties.html