pyDictStore
What is pyDictStore
pyDictStore add automated dictionary storage to properties eliminating the need for code bodies for property getters and setters with change event
Minimum usage
The minimum usage of this library requires you to ad the decoragotr @storage to your class. This will automatically automatically wrap your properties with the auto storage capabilities. The default value applied to any property is None. To override this you will need to apply the @default decorator to your propperties getter.
@storage
class ExampleClass():
@property
def exampleProperty(self): ...
@exampleProperty.setter
def exampleProperty(self,value): ...
...with default value
@storage
class ExampleClass():
@property
@default(10)
def exampleProperty(self) -> int: ...
@exampleProperty.setter
def exampleProperty(self,value) -> None: ...
Overriding the getter and setter
getter
If the getter returns a value other than None it will override the value pulled by pyDictStore. The example below will result in the property always returning 12.
@storage
class ExampleClass():
@property
@default(10)
def exampleProperty(self) -> int:
return 12
setter
Overriding the setter allows you to modify the value that is saved into storage. This is helpful if you need to perform logic against the value being passed in or if you want to force the storage type such as parsing an integer from a string or storing a boolean value as an integer. The critical aspect which is abnormal for a typical setter is that you need to return a value. The one limitation is that you can not pass a None value.
@storage
class ExampleClass():
@property
@default(10)
def exampleProperty(self) -> int: ...
@exampleProperty.setter
def exampleProperty(self,value) -> None:
return value * 3
Event Handling
When the setter of a property is called it will raise a PropertyChanged Event within your class. This provides you the instance of the class that raised the event, the name of the property, the previous value and the new value.
Its important to note that when the default value is instantiated in the property that the event will not fire.
...within class
@storage
class ExampleClass():
def __init__(self) -> None:
self.PropertyChanged += self.onPropertyChanged
@staticmethod
def onPropertyChanged(sender, name:str, oldValue, newValue):
... #Your Custom Action here
@property
@default(10)
def exampleProperty(self) -> int: ...
@exampleProperty.setter
def exampleProperty(self,value) -> None: ...
...outside of class
def onPropertyChanged(sender, name:str, oldValue, newValue):
... #Your Custom Action here
@storage
class ExampleClass():
def __init__(self) -> None:
self.PropertyChanged += onPropertyChanged
@property
@default(10)
def exampleProperty(self) -> int: ...
@exampleProperty.setter
def exampleProperty(self,value) -> None: ...
Library functions
Checks if an objects property is equal to its default value
Returns the default value of an objects property