AppBrewery - Quizzler

Question 1

setState call syntax

Answer 1

void setState( void Function fn)
setState( () { // ... } );

Question 2

Dart class syntax

Answer 2

class Name {
    // properties
    Name(){
        // constructor
    }

}

Question 3

pillars of OOP

Answer 3

. Abstraction
. Polymorphism
. Inheritance
. Encapsulation

Question 4

where to add classes

Answer 4

in lib folder

Question 5

abstraction

Answer 5

abstract away details of implementation; get to idea

Abstraction is the technique of hiding implementation. At it’s core there’s not much more to that answer. The bulk of meaning to abstraction come from how and why it is used.

It is used for the following scenarios

Reduce complexity. (Create a simple interface)
Allow for implementation to be modified without impacting its users.
Create a common interface to support polymorphism (treating all implementations of the abstracted layer the same.
Force users to extend the implementation rather than modify.
Support cross platform by changing the implementation per platform.

Question 6

encapsulation

Answer 6

separate jobs+roles of different objects/classes

It’s simply a containment of information.

Encapsulation means that a class publishes only what is needed for others to use it, and no more.

Question 7

enum syntax

Answer 7

enum Color { red, green, blue }

Question 8

how to make a property private

Answer 8

prefix _

_prop

Question 9

inheritance syntax dart

Answer 9

Subclass extends ParentClass

Question 10

inheritance concept

Answer 10

inherit common properties and functions from parent class

Question 11

polymorphism concept

Answer 11

changing shapes;
Poly = many
Morph = change or form
So polymorphism is the ability (in programming) to present the same interface for differing underlying forms (data types).

override common interface for custom subclass; e.g.

Shape super, .draw()
circle override .draw()
triangle override .draw()
many forms, one interface (draw)

Question 12

how to override in dart

Answer 12

@override

overriddenFunction () { //… }

Question 13

double

Answer 13

double data type in dart

Question 14

class constructor syntax for same parameter and class prop name

Answer 14

class MyClass {
  int prop;
  MyClass (this.prop)