vTech Solution Android Developer Interview Questions and Answers

A closure is a function that has access to its outer function's variables, even after the outer function has returned.

• A closure is created when a function is defined inside another function.

• It allows for private variables and functions in JavaScript.

• Closures are used for data hiding, encapsulation, and creating modules.

• Example: function outer() { var x = 10; function inner() { console.log(x); } return inner; } var clos

Basic structure of an HTML page includes doctype declaration, html, head, and body tags.

• DOCTYPE declaration specifies the HTML version

• HTML tag wraps the entire content of the page

• Head tag contains meta information, title, and links to external resources

• Body tag contains the visible content of the page

Padding is the space inside an element, while margin is the space outside an element.

• Padding is used to create space between an element's content and its border.

• Margin is used to create space between an element's border and the adjacent elements.

• Padding is affected by the background color of the element, while margin is not.

• Padding can be set individually for each side of an element (top, right, bottom, left), while ma...read more

Box Model is a concept in CSS where every element is treated as a box with content, padding, border, and margin.

• Box Model consists of content, padding, border, and margin.

• Content is the actual content of the box.

• Padding is the space between the content and the border.

• Border is the line that goes around the padding and content.

• Margin is the space outside the border.

Directives in Angular are markers on DOM elements that tell Angular to attach a specified behavior to that element.

• There are three types of directives in Angular: Component, Structural, and Attribute.

• Component directives are used to create reusable UI components.

• Structural directives are used to change the structure of the DOM.

• Attribute directives are used to change the appearance or behavior of an element.

• Examples of ...read more

JIT compiles code at runtime while AOT compiles code before runtime.

• JIT stands for Just-In-Time compilation and compiles code at runtime.

• AOT stands for Ahead-Of-Time compilation and compiles code before runtime.

• JIT is used in Java Virtual Machine (JVM) while AOT is used in languages like C and C++.

• JIT can result in slower startup time but faster execution while AOT can result in faster startup time but slower execution...read more

Object-Oriented Programming (OOP) concepts in Java

• Encapsulation: wrapping data and methods into a single unit

• Inheritance: creating new classes from existing ones

• Polymorphism: ability of objects to take on multiple forms

• Abstraction: hiding implementation details from users

• Interfaces: defining a set of methods that a class must implement

• Classes: blueprint for creating objects

Name mangling is a technique used by compilers to give unique names to functions and variables to avoid naming conflicts.

• Name mangling is used in C++ to support function overloading.

• It is also used in Python to avoid naming conflicts in modules.

• Name mangling can make it difficult to access variables and functions from outside the class in which they are defined.

• In C++, name mangling can be seen by using the 'nm' comman