When you write a = value, you are calling the property setter again. In order to use non-automatic properties, you need to create a separate private backing field, like this: ConstraintSet a; public ConstraintSet A { get { return a; } set { a = value; } }
Multiple reasons: If you allow field access like shape.x = 90 then you cannot add any logic in future to validate the data. say if x cannot be less than 100 you cannot do it, however if you had setters like public void setShapeValue(int shapeValue){ if(shapeValue < 100){ //do something here like throw exception. } … Read more
The WPF binding engine calls GetValue and SetValue directly (bypassing the property setters and getters). You need the property to be there so it can be supported in the XAML markup (and compile correctly).
If you want to validate when the property is set, you need to use non-auto properties (i.e., manually defined get and set methods). But another way to validate is to have the validation logic separate from the domain object. class Customer { public string FirstName { get; set; } public string LastName { get; set; … Read more
Use just the .getter decorator of the original property: class superhuman(human): @human.name.getter def name(self): return ‘super ‘ + self._name Note that you have to use the full name to reach the original property descriptor on the parent class. Demonstration: >>> class superhuman(human): … @human.name.getter … def name(self): … return ‘super ‘ + self._name … >>> … Read more
The “CLR-wrappers” for dependency properties only get called when done through code. XAML depends on the name specified in the DependencyProperty.Register(…) call. So, instead of “extending” the logic of the setter for your dependency property like you did above, just put your custom logic in a PropertyChangedCallback function.
Looking through the nowjs source code, I believe they do this by continuously monitoring the now object and pushing changes between client and server whenever they are detected. I admit I haven’t fully grokked their code yet, however. In a browser, this would be done with some fun setInterval hacks. EDIT: yes, that is indeed … Read more
I don’t have a problem with Holub telling you that you should generally avoid altering the state of an object but instead resort to integrated methods (execution of behaviors) to achieve this end. As Corletk points out, there is wisdom in thinking long and hard about the highest level of abstraction and not just programming … Read more
You should use the constructor approach, when you want to create a new instance of the object, with the values already populated(a ready to use object with value populated). This way you need not explicitly call the setter methods for each field in the object to populate them. You set the value using a setter … Read more
I have personally settled on using an underscore prefix for ivars, and this kind of synthesize @synthesize name = _name; That way I don’t mix them up. The major issue with not using self is that this code _name = … is very different from self.name = … When the @property uses the retain option. … Read more