My first React native app - Simple weather app

I'm learning the react native and today I'll write a post about my first app - Simple weather app (from a to z) to apply what I have learned.

source https://github.com/jbohnvn/reactnative

I'm a window and android boy so this tutorial only run with android, so if you guys can run it on iOS please comment, then other people can get it as an example as well.

Requirements:
- Familiar with JavaScript and React
- Nodejs, Android SDK installed on your local machine
- VSCode is using (but you can use any other IDE or editor)
- Having Weather API - OpenWeatherMap account for get API KEY
...let's start

Creating a new project

Use the react native command line interface to generate a new React Native project

npm install -g react-native-cli
react-native init AwesomeProject
cd AwesomeProject
react-native run-android

Make sure you installed android build version defined in SimpleWeather/android/build.gradle

 ext {
        buildToolsVersion = "27.0.3"
        minSdkVersion = 16
        compileSdkVersion = 27
        targetSdkVersion = 26
        supportLibVersion = "27.1.1"
    }

Really eager to write more code now...

The Prototype
In this step, we develop our first screen, which will be a simple loading screen.
In your App.js, define a local state:


Check out the weather response

Request:

http://api.openweathermap.org/data/2.5/weather?lat=37.4219983333333&lon=-122.0840000&APPID=<<REPLACE_BY_YOUR_API_KEY>>&units=metric

We will get lat and lon by piece of code in App.js


Response: 
We will get below information to display
- temperature: json.main.temp,
- weatherCondition: json.weather[0].main,
- position : { country : json.sys.country, name : json.name }
Create Weather component 

Very nice, now we have weather information, we will create a Weather component to display them:

We put the information corresponse to TextViewes and creating a dynamid backgroud base on weather condition:  <View style={[styles.weatherContainer,{ backgroundColor: weatherConditions[weather].color }]}
Integrate with App component
HOPE YOU GUY ENJOY THIS TUTORIAL!!!

Single responsibility priciple

Single-responsiblity principle (S.R.P) - this principle states that:

A class should have one and only one reason to change, meaning that a class should have only one job.

For example, say we have some shapes and we wanted to sum all the areas of the shapes. Well this is pretty simple right?

class Circle {
    public $radius;

    public function __construct($radius) {
        $this->radius = $radius;
    }
}

class Square {
    public $length;

    public function __construct($length) {
        $this->length = $length;
    }
}

Core Software Design Principles

Things need to know to become a hardcore Java developer

1. Multithreading, concurrency and thread basics
2. Date type conversion and fundamentals
3. Garbage Collection
4. Java Collections Framework
5. Array
6. String
7. GOF Design Patterns
8. SOLID design principles
9. Abstract class and interface
10. Java basics e.g. equals and hashcode
11. Generics and Enum
12. Java IO and NIO
13. Common Networking protocols
14. Data structure and algorithm in Java
15. Regular expressions
16. JVM internals
17. Java Best Practices
18. JDBC
19. Date, Time and Calendar
20. XML Processing in Java
21. JUnit

Measurement of code quality