What is happening is that each subview inside the TableViewCell will receive the setSelected and setHighlighted methods. The setSelected method will remove background colors but if you set it for the selected state it will be corrected. For example if those are UILabels added as subviews in your customized cell, then you can add this … Read more
It seems Swashbuckle doesn’t implement polymorphism correctly and I understand the point of view of the author about subclasses as parameters (if an action expects an Animal class and behaves differently if you call it with a dog object or a cat object, then you should have 2 different actions…) but as return types I … Read more
Because every instance of the subclass still needs to be a valid instance of the base class (see Liskov substitution principle). If the subclass suddenly has lost one property of the base class (namely a public method for example) then it would no longer be a valid substitute for the base class.
There is now an official guide on how to subclass Pandas data structures, which includes DataFrame as well as Series. The guide is available here: https://pandas.pydata.org/pandas-docs/stable/development/extending.html#extending-subclassing-pandas The guide mentions this subclassed DataFrame from the Geopandas project as a good example: https://github.com/geopandas/geopandas/blob/master/geopandas/geodataframe.py As in HYRY’s answer, it seems there are two things you’re trying to accomplish: … Read more
Overwriting __new__() works if you want to modify the string on construction: class caps(str): def __new__(cls, content): return str.__new__(cls, content.upper()) But if you just want to add new methods, you don’t even have to touch the constructor: class text(str): def duplicate(self): return text(self + self) Note that the inherited methods, like for example upper() will … Read more
Let’s look at this definition: public class Extend1<T, E> extends MyGeneric<T, E> {} Here T and E are each present twice and in two different roles in Extend1<T,E> you define type arguments. This means that the type Extend1 has two (unbounded) type arguments T and E. This tells the Java compiler that those who use … Read more
Member variables cannot be overridden like methods. The number variables in your classes Beta and Gama are hiding (not overriding) the member variable number of the superclass. By casting you can access the hidden member in the superclass.
The problem is that you’re making a promise that the compiler can’t prove you’ll keep. So you created this promise: Calling copy() will return its own type, fully initialized. But then you implemented copy() this way: func copy() -> Self { return C() } Now I’m a subclass that doesn’t override copy(). And I return … Read more