class

问题 I have created a button class in pygame and although the button itself is displaying, my text is not showing up. Also I have some conditions to change the colour when the mouse is over the button. I have achieved the desired result using hard coded values in my main function, however I want to use a class the handle my various button as I might have quite a few buttons. Given below are some classes that I'm using Fonts class Fonts: def __init__(self, font, antialias, text, color, x, y): self

问题 So there are two classes in separate header files Customer. h using namespace std; #include <iostream> class Customer{ friend void Display(); private: int number, zipCode; public: Customer(int N, int Z){ number = N; zipCode = Z; } }; City. h using namespace std; #include #include "Customer.h" class City{ friend void Display(); private: int zipCode; string city, state; public: City(int Z, string C, string S){ zipCode = Z; city = C; state = S; } }; my main.cpp is as follows #include "City.h"

问题 I created a simple class component with some props. Since Typescript 3 and above, they state that defaultProps by default will use the same Interface as the component's props itself. reference In the following code example, you can see I created a component, extending React.PureComponent with a given interface. One prop is called boolean with type boolean. Then I got the static defaultProps assignment where I made an "accidental" typo where I put a string instead of a boolean. import React

问题 I am working on WinForms using C#. I made a class video that has method yourvideos() . This method reads data from SQL database and add it in imagelist and listview . First I have uploaded the image and then take the location of image using: var=open.FileName.ToString(); Then in a function uploadvideo() , I converted image to bytearray and inserted it to database: public void uploadvideo(string url, string path, string name,string title, DateTime date, string imgloc, string user) { con.Open()

问题 This question already has answers here : how to unwrap swift optionals within a struct (1 answer) What does “Fatal error: Unexpectedly found nil while unwrapping an Optional value” mean? (11 answers) Closed 8 months ago . as an old C programmer I am trying to get into Swift. I have already overcome many hurdles but for the following I am out of ideas. I am building a little home schooling app and want to store/retrieve the high scores to/from a JSON file. import Foundation struct HighScores:

问题 This question already has answers here : Is it unnecessary to put super() in constructor? (6 answers) Closed 6 years ago . I always thought that when creating an object with a sub-class, we need to explicitly use super(arguments list) to call the constructor of the super class. However I did an experiment and realize that even without using the super() , the super class's constructor will be called automatically. Is this true? If this is true, when is super() redundant and when it is not?

问题 I'm currently setting-up my application, and i need to manage a json file (that contain some settings) in my windows form. Once you open it, you can easy choose different settings, and once you've done, you can save it (which mean i need to overwrite the existing one json file settings, and replace it with new one! I tried to follow this guide for correctly create my json file! But i met 2 problems: This solution mentioned up, create square brackets (which i don't need!) Seems to create all

问题 Let's for example define a class and a function class class1(object): """description of class""" pass def fun2(x,y): x.test=1; return x.value+y then define a class instance and run it as a local variable in the function z=class1() z.value=1 fun2(z,y=2) However, if you try to run the code z.test a result 1 would be returned. That was, though the attribute to x was done inside the fun2() locally, it extended to class instance x globally as well. This seemed to violate the first thing one learn

问题 In python, what is the difference between protected and public variable in a class class A: def __init__(self): self._protected="protected" self.__private="private" self.public="public" >>> a = A() >>> a.public 'public' >>> a._protected 'protected' >>> Can someone please explain me the difference, and guide me on how to use protected variable in python [In case my method is usage is false] Thanks in Advance. 回答1: None of those terms except "public" really apply in Python. The "private"

问题 In my current programming class I've been tasked with creating a program that takes user input course (Consisting of course name, course grade, course units variables) and storing them in a dynamically generated array with a maximum size of 10. Due to my unfamiliarity with object oriented programming and classes however I'm finding anything beyond the pure creation of the classes to be very difficult. I've figured out a way to create the entries, as well as how to edit them after they've been