Instantiate subclass without constructing

Instantiate subclass without constructing

Content Index :

Instantiate subclass without constructing
Tag : javascript , By : Thx1138.6
Date : January 12 2021, 01:40 AM

I wish this helpful for you I would use an initialization function separate from the constructor as that give you more control over when/if parent initialization happens.
class Parent {
  constructor(x) {
    console.log("parent constructor does other stuff");
  init(x) {
    console.log("parent init runs")

class Child extends Parent {
  constructor(x) {

  init(x) {
    console.log("child init runs");
    super.init(x); // This call is optional if you don't want to run the parent's init code

let c = new Child();

No Comments Right Now !

Boards Message :
You Must Login Or Sign Up to Add Your Comments .

Share : facebook icon twitter icon

How does this subclass instantiate itself?

Tag : objective-c , By : B3CFT
Date : March 29 2020, 07:55 AM
Hope this helps When you call [super something], you are using the superclass's implementation of the method, but the method is still called on the same object that the current method is called on. In other words, the self in the super call is the same as the self in the current function -- the PKAnimation class (or whatever class you called this method on).
This depends on knowing that +[CABasicAnimation animationWithKeyPath:] creates an object of the class that it's called on. But this is a convention that is followed by all convenience constructors in Cocoa. They always create the object using [self alloc] ... rather than [SomeSpecificClass alloc] ..., therefore, it will always use the class object that the method (which may be inherited) is called on at runtime, not the class that the code is physically in at compile time.

Constructing a Subclass Object in a Completely Different Class

Tag : java , By : browe
Date : March 29 2020, 07:55 AM
I wish this help you As @tsnorri mentioned in comment, you should simply declare Rectas class out of Shapeone.
public class Shape {


public class Rect extends Shape {
    //rect instance variables
    public Rect(){
        System.out.print("Youve made a rect within shape");
import java.util.ArrayList;

class ImageMaker
    static ArrayList<Shape> shapes = new ArrayList<Shape>();//all the shapes contained in the image

    public static void main(String args[])
        shapes.add(new Shape());
        shapes.add(new Rect());

    public static class Shape {
        System.out.print("Created new Shape");

    public static class Rect extends Shape {
        //rect instance variables
        public Rect(){
            System.out.print("You've made a rect within shape");

What's wrong with my way of constructing an object of a subclass?

Tag : cpp , By : WuJanJai
Date : March 29 2020, 07:55 AM
I think the issue was by ths following , Here's my subclass: , I think you have
class CChildView : public CWnd
    // ...
    BackGround Bg1(0);                // Line 46
    BackGround Bg2(-WINDOW_HEIGHT);   // Line 47
class CChildView : public CWnd
    // ...
    BackGround Bg1 {0}; 
    BackGround Bg2 {-WINDOW_HEIGHT};
class CChildView : public CWnd
    // ...
    BackGround Bg1; 
    BackGround Bg2;

// ... 

CChildView::CChildView() : Bg1(0), Bg2(-WINDOW_HEIGHT)
    // ...

Python: Constructing a multiple-inheritance subclass instance from a superclass

Tag : python , By : Mena
Date : March 29 2020, 07:55 AM
will be helpful for those in need Bugs are already there - when you do self.gates = circuit.gates, circuit.gates being a list, yu point both references to the same list - and if this list is updated on the original circuit, this update will be reflected in your subcircuit instance.
I think the most sane pattern tehre is to have an alternate constructor for the class if you have a circuit instance from which to update your own:
from copy import copy
class SubCircuit(Gate, Circuit):
    def __init__(self, size):
        Gate.__init__(self, size)
        Circuit.__init__(self, size)

    def from_circuit(cls , circuit, size):
        self = SubCircuit(size)
        for key, value in circuit.__dict__.items():
             setattr(self, key, copy(value))
        return self

How to instantiate subclass from within a superclass

Tag : java , By : user150744
Date : March 29 2020, 07:55 AM
Related Posts Related QUESTIONS :
  • Would I be able to give access to specific electron APIs safely?
  • Why several clicks fire for each instance of a Class?
  • cant grab value from div using attr()
  • Make web service not accessible by browser?
  • Select DOM elements within template
  • How to customize angular ui-grid row background color?
  • Binding data in two respective $scope in AngularJS, how?
  • react put some props after import class
  • Variable is distributed among same components
  • switch class in jQuery/JavaScript for active/inactive state
  • How To Track Outbound Clicks Using Javascript
  • How to get total seconds elapsed since the beginning of the month?
  • Protractor: Stale element reference at "browser.wait(EC.visibilityOf(confDial), FIFTY_SECONDS);"
  • Access to an array inside an object
  • Reseting an JavaScript Interval with different value?
  • Learning Angular for the first time - version 2 or 4?
  • Rendering RSS feed (XML) in React with jquery, why do object values parsed from the feed seem empty?
  • Node.js xml2js http.request tag matching
  • applying texture to custom plane geometry in Threejs
  • How do I pass an Event as a function parameter in HTML written inside JavaScript variable?
  • Interface of object parameter with default value and default property
  • Does using try / catch rather than `.catch` observable operator with XHR requests reduce performance?
  • In IE11 background colors not working on printing
  • TypeScript interface signature "(): string"
  • Is synchronous XMLHttpRequest supported in Internet Explorer 10 and 11?
  • Axios function not returning any values with js
  • How to use firestore TIMESTAMP to create time-stamp in JavaScript
  • Outputing a created object in javascript to a server side JSON file
  • Transition the numeric labels in a bar chart
  • createBottomTabNavigator: hide just one tab from the tabBar
  • iife vs simple statement behavior with document.title
  • showDialogPopup Refresh Page after Click
  • Child component does not set the initial value passed from the parent: ReactJS
  • Nodejs javascript added to button not responding
  • Trying to define a promise.all
  • Python GEE to extract featurecollection timeseries from Landsat imageries
  • How to write negative binary number?
  • Unable to set property of individual object
  • Why Named Function Expression itself cannot assign Name to another Value?
  • How to reset scroll position on single page pagination
  • How to scroll to bottom of page, when a new message is sent - Socket.io
  • How to reconstruct audio blob from a base64 encoded String?
  • How to calculate numbers within an array of objects
  • Using JavaScript to change CSS properties of SVG circles for all circles that was not clicked
  • Is there value in propTypeing repeat required properties at every level of nested components?
  • Call function if variable does not exist in a filter
  • localStorage value doesn't get updated automatically
  • React not updating state with setState correctly inside promises
  • Direct native JavaScript or jQuery method to get containing block of an element
  • Dynamic JSON object to Html Table
  • How to send Id and file to same controller?
  • How to Make a jQuery Table Cell(td) clickable to Run a Function?
  • Prevent the duplicate function onchange event jQuery
  • Reactjs Input Upload doesn't return local URL
  • An unexpected 'StartObject' node was found when reading from the JSON reader. A 'PrimitiveValue' node was expected
  • How to filter a JSON Array, with an eventListener input value at keyup
  • How to separate the different properties of filter in css?
  • Why dont work change event of bootstrap input spinner?
  • How to hide overflow text content in react
  • Is there another way to write line 6
  • shadow
    Privacy Policy - Terms - Contact Us © scrbit.com