Flutter training in Chennai

1)What is Automation Testing and benefits?
============================================
*Test Automation is a process that makes use of automation testing tools to execute pre-scripted tests on applications, then compares the test results to the expected behavior and reports it to the testers.
Benefits:
---------
*It execute tasks automatically
* increase effectiveness
*efficiency
*coverage of the software testing.

2)Why should Selenium be selected as a test tool?
==================================================
*Selenium is an open source automation testing tool which is used to test web applications.
*Selenium testing tool is also consists of different set of tools in it like Selenium WebDriver, Selenium RC, Selenium IDE which has different features.

3)What is Selenium? What are the different Selenium components?
================================================================
*Selenium is a portable software testing framework for web application.
*Selenium provides a playback tool for authoring tests without need to learn a test scripting languages.
Different selenium components:
------------------------------
*Selenium IDE
*Selenium RC
*Selenium Webdriver
*Grid

4)What is the difference between Selenium RC, and WebDriver?
=============================================================
Selenium RC:
-----------
*It is less object-oriented API,this API supports a particular browser.
Selenium WebDriver:
------------------
*whereas Selenium WebDriver is purely object-oriented API.This is an API which is not bound to a specific browser i.e. supported by almost every browser.

5)What is the latest version of selenium jar file and how you will configure selenium jar file with eclipse?
=============================================================================================================
Latest version:
---------------
*3.14.159
Configure jar file:
--------------------
*We have to give add to build path for configuration.

6)Can Google Chrome will be supported by Selenium IDE?
=======================================================
*No,Google Chrome will not be supported by Selenium IDE.

7)What are the different browsers supported by selenium?
==========================================================
*Firefox browser
*Chrome browser
*IE
*safari browser
*Opera browser

8)What is the Classname,driver name for the below browsers?
===========================================================
Browser Class
------- ------
1.Firefox browser-->FireFoxDriver
2.Chrome browser -->ChromeDriver
3.IE -->InternetExplorerDriver
4.safari browser -->SafariDriver
5.Opera browser -->OperaDriver

9)What is the WebDriver ? Whether WebDriver is class or interface?
===================================================================
*Webdriver is a web automation framework that allows you to execute your tests againts different browser,not just firefox.
*Webdriver also enables you to use a programming languages in creating your test script.
*Webdriver is a interface.

10)What is the method name to launch the url?
=============================================
*get()- used to lanuch the url.

11)What are the Method names to get the title and current URL?
===============================================================
*getTitle()- used to get the title of the webpage.
*getCurrentUrl()-used to get the current url of the webpage.

12)What is the difference between close() and quit()?
======================================================
close():
--------
*It will close the current window only.
quit():
-------
*It will close all opening window and browser.

13)What are the methods available in webdriver?
================================================
*close();
*findElement();
*findElements();
*get();
*getTitle();
*getCurrentUrl();
*manage();
*quit();
*switchTo();

14)What is the use of WebDriver?
==================================
*It is mainly used for providing the connection between the browser and local system.
*It act as a bridge.

15)What are the locator available in selenium?
===============================================
*id
*classname
*name
*Xpath
*CSS selector
*link Text
*partially Link Text
*tagname

16)Which locator is fastest in selenium?
=======================================
*id is the fastest locator in selenium.

17)How will you find the locators in selenium? write a code for it?
===================================================================
*We can find the locator by using findElement(),findElements() methods.
Code
-----
driverrefname.findElement(By.locator("values");

18)Explain about findElement & findElements?
=============================================
*Both are used to find the webelement from the webpage.
*findElement find one webelement.
*findElements find the list of web element.

19)Difference between findElement and FindElements?
===================================================
findElement
------------
*It find only one webElement.
*If no element is found it throws no such element exception.
findElements
-------------
*It finds a list of webElement.
*findElements will return an empty array when no elements found

20)What is the return type of findElement and findElements?
===========================================================
*findElement - WebElement
*findElements - List

21)In which class all the locator methods are available?
=========================================================
*In By class all the locator methods are available.

22)What is method to insert a value in textbox?
=================================================
*sendKeys() method is used to insert a value in textbox.

23)Write a code for inserting value in textbox?
================================================
*WebElementRefname.sendKeys("values");

24)Whether in finding the locator index will start from 0 or 1?
=================================================================
*For selecting first locator we pass 1 in the index.

25)How will you click a button in webpages?
============================================
*By using click() method we can click a button in webpage.

26)Whether WebElement is a interface or class?
===============================================
*WebElement is a interface.

27)What is mean by System.setProperty?
========================================
*System is a class.
*.setProperty is a method in this we have to pass key and value.
*It is used to set the class and path location of driver.

1)What is java?
================
*Java is a simple programing language.
*Writing, compilation and debugging a program is very easy in java.
*It helps to create reusable code.

2)Why are we go for java?
==========================
*It is a platform independent and open soruce.
*It runs multiple application at a time.

3)What are the main features of java?
=====================================
*Java has more features,
1. Platform independent
2. Open source
3. Multithreading
4. More secure
5. Portable

4)What is platform independent?
================================
*During the compilation the java program converts into byte code.
*Using byte code we can run the application to any platform such as windows, mac, linux, etc..

5)What is mean by Open Source?
===============================
*A program in which source code is available to the general public for use and/or modification from its original design at free of cost is called open source.

6)What are types of tools are used to execute java?
===================================================
*Notepad
*Net bean
*Eclipse
*J Developer(oracle)
*RAD(IBM)

7)What are difference between JDK,JVM,JRE?
==========================================
JDK:
----
*Java Development Kit.
*If we want to run any applications in java we need JDK have to installed.
*JDK versions: 1.0 to 1.10.
JRE:
----
*Java Runtime Environment.
*It is a pre-defined class files (i.e.) library files.
JVM:
----
*Java Virtual Machine.
*It is mainly used to allocate the memory and compiling.

8)What is mean by oops?
=======================
*OOPS is Object Oriented Programing Structure.
*OOPS is a method of implementation in which programs are organized as collection of objects, class and methods.

9)What are the coding Standard used in java?
=============================================
*Pascal notation: Each and every word of the first letter should be in capital. Example:GreensTechnology
*Camel notation: First word should be small after every word of the first letter should be capital. Example:greensTechnology

10)What is mean by class,method,object?
=======================================
Class:
------
*Class is nothing but collection of methods or collection of objects.
Method:
-------
*Method is nothing but set of action to be performed.
Object:
-------
*Object is the run time memory allocation.
*Using object we call the any methods.

11)What is mean by Encapsulation?
=================================
*It is the structure of creating folders.
*It wraps the data and code acting on a data together in to a single unit.
*Example of encapsulation POJO class.

12)What are the datatypes used in java?
=======================================
*byte
*short
*int
*long
*float
*double
*boolean
*char
*String

13)What is byte size and range of int datatypes?
==================================================
*Size of byte is 1 byte (8 bit)
*Range formula =[-2^(n-1)] to [(2^(n-1))-1] for int n=32.

14)What is mean by Wrapper class?
=================================
*Classes of data types is called wrapper class.
*It is used to convert any data type into object.
*All classes and wrapper classes default value is Null.

15)What is the main use of Scanner class?
=========================================
*For getting the inputs from the user at the run time.

16)What are the methods available in Scanner Class?
====================================================
*nextByte();
*nextShort();
*nextInt();
*nextLong();
*nextFloat();
*nextDouble();
*next().charAt(0);
*next();
*nextLine();
*nextBoolean();

17)What is mean by inheritance?
===============================
*We can access one class property into another class using 'extend' keyword and reusuable purpose.
*It avoid memory wastage.

18)What are the ways to access the methods /data from another class?
=====================================================================
*We can access the another class methods either by creating object or use extends keyword.

19)What is mean by polymorphism?
================================
*Poly-many.
*Morphism-forms.
*Taking more than one forms is called polymorphism or one task completed by many ways.

20)What are the difference between method overloading and overriding?
=====================================================================
Method overloading(static binding/compile time polymorphism):
-------------------------------------------------------------
*Class-same
*Method-same
*Argument-differ based on datatype,order,number
Method overriding(dynamic binding/run time polymorphism):
----------------------------------------------------------
*Class name-differ(using extends)
*Method-same
*Argument-same

1) What is Dart?

Dart is an open source language developed in Google with the aim of allowing developers to use an object-oriented language with static type analysis. Since the first stable release in 2011, Dart has changed quite a bit, both in the language itself and in its primary goals. With version 2.0, Dart's type system went from optional to static, and since its arrival, Flutter (we'll explain later) has become the main target of the language. 

2) What are the Data Types in Dart?

• Numbers
• Strings.
• Booleans.
• Lists.
• Maps. 

3) What is List and Map in Flutter?

List, Map are the four types of collection in Dart programming language. List is iterable while Maps are not. Iterable collections can be changed i.e. their items can be modified, add, remove, can be accessed sequentially. The map doesn't extend iterable.

Lists are the most popular elements of every web or mobile application. They are made up of multiple rows of items, which include text, buttons, toggles, icons, thumbnails, and many more. We can use it for displaying various information such as menus, tabs, or to break the monotony of pure text files.

A map, also known commonly as a dictionary or hash, is an unordered collection of key-value pairs. Maps pair a key with a value for easy, fast retrieval. Like lists and sets, maps can be declared with a constructor or literal syntax. Sets and maps have the same syntax for their literal implementation.

 4) What is Flutter? Why we use dart here?

Flutter is a great choice for cross-platform mobile app development when you need your app to be fast, beautiful, and perform well. Additionally, if you need to reach a global audience, Flutter is the best option as it supports internationalization.

Flutter is a cross-platform software development kit (SDK) for mobile app development that was created by Google. Flutter uses Dart programming language and it is used to create apps for Android and iOS devices. Because it is cross-platform, a single code base can be used to create apps with a native look and feel on both Android and iOS devices.

The first version of Flutter was known as "Sky" and ran on the Android operating system. Initial Release Alpha (0.0.6) /May 12, 2017.

Flutter code can run on desktop, mobile, and web platforms. So, you don't need to hire developers for each platform. You need to write the code only once in Flutter and you can rest assured that the app will work across the other platforms. So, Flutter is cheap. 

5) Name some editor for flutter development.

• Android Studio
• Visual Studio Code
• IntelliJ IDEA
• Emacs (Dart Mode)
• Atom
• Sublime Text 

6) What are the types of widgets in flutter?

Stateless and Statefull widgets. 

7) Why is the build() method on State and not Statefull Widget?

Putting a Widget build(BuildContext context) method on State rather than putting a Widget build(BuildContext context, State state) method on 

StatefulWidget    gives    developers    more    flexibility    when    subclassing StatefulWidget. 

8) Difference between runApp() and main().

The main() function is responsible for starting the program. Without the main() function, we cannot write any program on Flutter.

The runApp() function is responsible for returning the widgets that are attached to the screen as a root of the widget tree and will be rendered on the screen. 

9) Say about Stateless and Statefull widget.

The widgets whose state cannot be altered once they are built are called stateless widgets. These widgets are immutable once they are built i.e any amount of change in the variables, icons, buttons, or retrieving data cannot change the state of the app. Stateless widget overrides the build() method and returns a widget. The state of a stateless widget is not meant to change. A stateless widget is supposed to manage states/situations that don’t get affected by a user’s input.

A Stateful Widget has states in it. To understand a Stateful Widget you need to have a clear understanding of widgets and state management. “an imperative changing of the user interface” and, a widget is “an immutable description of the part of user interface”. The widgets whose state can be altered once they are built are called stateful Widgets.

These states are mutable and can be changed multiple times in their lifetime. This simply means the state of an app can change multiple times with different sets of variables, inputs, data.

Stateful widget overrides the createState() and returns a State. 

10) Why does the first flutter app build take so long?

When building a Flutter app for the first time, a device-specific APK or IPA file is built. Hence, Gradle and XCode are used to build the files, taking time. The next time the app is restarted or hot-reloaded, Flutter essentially patches the changes on top of the existing app giving a blazing fast refresh. 

Note: The changes made with hot reload or restart ARE NOT SAVED on the device APK or IPA file. To ensure your app has all your changes on-device, consider stopping and running the app again.

11) Say some details about MaterialApp and Scaffold

MaterialApp is a widget that introduces the Navigator and Theme widgets required to create a material design app. Scaffold Widget is a MaterialApp component that provides numerous fundamental features such as AppBar, BottomNavigationBar, Drawer, FloatingActionButton, etc. 

12) What are the limitation of flutter?

• Few third-party packages
• Inability to call Native APIs from Dart directly
• Requirement of Dart for development
• Lack of code push
• Few digital platforms
• Little overall Support
• Limited complexity
• Vector graphics and animations support 

13) Explain packages and plugins in flutter

Flutter plugins are thin Dart wrappers on top of native (Java, Kotlin, ObjC, Swift) mobile APIs and services. For instance, if you wanted to access a sensor on the phone, the only way is to write a plugin (or use one that’s already there).

The API of the plugin is written in Dart. The implementation of the plugin is written in either Java/Kotlin (for Android support), in ObjC/Swift (for iOS support), or both (for cross-platform support). Plugins today are not trivial to test end-to-end.

Plugins are also (special) Dart packages. They get published to Pub and you interact with them via their Dart interface. The main difference between the

two is that with a pure Dart package you don’t need to write any native code and testing is a breeze.

14) In flutter, property and widget word’s letter must be?

Property: small letter

Widget: capital letter

15) Why we use Setstate?

setState() allows you to change state in a React class component. To change the state of a function component, you use the useState() hook. Learn more about it here. setState() enqueues change to the component state and tell React that this component and its children need to be re-rendered with the updated state.

16) What is layout and widget?

The Layout Widget is a responsive container that allows you to separate a responsive container into sections. Layouts can be placed inside the responsive containers of other layouts to create more even sections. 

17) In what technology is flutter build?

Flutter is built with C, C++, Dart, and Skia (a 2D rendering engine). 

18) How to remove the debug label?

In the top right corner there is a DEBUG banner. To remove this you can use debugShowCheckedModeBanner property of MaterialApp() widget.

debugShowCheckedModeBanner: false 

19) Why the Android and iOS folder in the flutter project?

Android folder and ios folder are the folders exist to actually build an app on those respective platforms with the Dart files running on them. They also help you add permissions and platform-specific functionality to your project.

20) Some function given in stateless widget, does it work?

No, the state of a stateless widget is not meant to change. A stateless widget is supposed to manage states/situations that don’t get affected by a user’s input.

21) I want to move one page to another and return to first page, what are the possibilities, answer with code

onPressed: () {

Navigator.push( context,

MaterialPageRoute(builder: (context) => const SecondRoute()),

);

}

onPressed: () {

Navigator.pop(context);

}

22) What is Material and Cupertino Widget?

Material widgets implements the Material design language for iOS, Android, web, and desktop. Cupertino widgets implements the current iOS design language based on Apple's Human Interface Guidelines. 

23) Explain pubspec.yaml file? Expand yaml.

The pubspec file specifies dependencies that the project requires, such as particular packages (and their versions), fonts, or image files. It also specifies other requirements, such as dependencies on developer packages (like testing or mocking packages), or particular constraints on the version of the Flutter SDK.

YAML stands for yet another markup language

24) Why we use the SafeArea Widget?

SafeArea class Null safety. A widget that insets its child by sufficient padding to avoid intrusions by the operating system. For example, this will indent the child by enough to avoid the status bar at the top of the screen. 

25) What are the advantages in flutter?

• Flutter is a Cross-platform Development Framework.
• Same UI and Business Logic in All Platforms.
• Fast Development due to “Hot Reload” feature.
• Highly Customizable UI Design.
• A Wide Variety of Rich Widgets.
• Access to Native Features.
• Publicly Accessible.