[JAVA] How to study kotlin for the first time ~ Part 1 ~

As many people have written, I would like to explain my study method and the time it took to learn it. I will write it for reference. The reference time is written a little longer.

--Program experience (experience as a business) --No solid object-oriented development experience --java no experience --No kotlin experience

First thing I did

I took a look at the Kotlin reference

Time required: 4 hours

Kotlin Koans

It didn't make sense at all and I was easily frustrated.

Do you want to start with java ... www

I became a disciple of Dot Install

Time required: 60 hours I learned the basic knowledge of java android. This is the basics, so I tried to understand it well. It was easy to understand because you can do it while moving your hands from the introduction.

--Introduction to java8 --Introduction to android application development --Introduction to android layout --Introduction to android list view () --Introduction to android database ()

When I think about it now, there are various notations for the (*) part. I think it was enough to remember it as a magic.

I took a class to make an app with java android

Time required: 40 hours Actually, the library and the current version have a newer way of writing. The emphasis here is on getting a feel.

I just googled for something I didn't understand. I skipped the ones that I couldn't understand even after searching for an hour, thinking that it was such a thing.

-[Old version] Let's make a stopwatch on Android -[Old version] Let's make a fortune app on Android --Let's make a first and last name diagnostic app on Android --Let's make a quiz app on Android --Let's make a web browser on Android --Let's make a memo app on Android

ʻIt doesn't take much time except to make a memo app on Android`. I learned a lot here because there is a database connection at the memo app

View open source

Time required about 8 hours fossdroid

Try moving the appropriate one here locally and write it like this-like I was allowed to refer to it. Dot Install can't cover all the apps, so you can use multiple apps. It's time to take a quick look and discover that "Oh, I can do this."

Practice 1

Time required 90 hours

At this point, it is possible to create an android application that actually works. Let's see it. However, the code is dirty. But at this stage you don't have to worry about it at all. Decide what you want to make and make it appropriately. The goal is to move the app. I don't care about test code at this stage w

java ends here

Impressions so far

I feel like I've used it for about 200 hours in total. The thing to note is that up to this point, you should "move your hands for the time being" to get a feel for it.

There are some difficult syntaxes (annotations, lambda expressions, etc.), I think you'll be frustrated as soon as you touch it now. It feels good to be able to "actually move what you think".

We'll get into Kotlin in the next chapter, but if you do this far, you'll get into it smoothly. Let's learn difficult syntax from now on ★ Let's do our best! !!

Following section First-time kotlin study method-Part 2-

Recommended Posts

How to study kotlin for the first time ~ Part 2 ~
How to study kotlin for the first time ~ Part 1 ~
Introduction to java for the first time # 2
Spring Boot for the first time
Spring AOP for the first time
Modeling a Digimon with DDD for the first time Part 1
Touching kotlin for the first time-Enum Classes
[Java] How to set the Date time to 00:00:00
Learning for the first time java [Introduction]
kotlin & Java: How to hide the toolbar only for specific fragments
The story of releasing the Android app to the Play Store for the first time.
Walls hit by Rspec for the first time
[For beginners] How to implement the delete function
Android Studio development for the first time (for beginners)
[Java] (for MacOS) How to set the classpath
I tried touching Docker for the first time
[Ruby on Rails] When logging in for the first time ・ How to split the screen in half using jQuery
How to set the display time to Japan time in Rails
Learn for the first time java # 3 expressions and operators
Oreore certificate https (2020/12/19) for the first time with nginx
Learning memo when learning Java for the first time (personal learning memo)
How to make a mod for Slay the Spire
Command to try using Docker for the time being
SDWebImage: How to clear the cache for a particular UIImageView
[Rails] I tried using the button_to method for the first time
How to create a placeholder part to use in the IN clause
How to cure the time dilation when launching Japaneseized Kibana
A summary of what Java programmers find when reading Kotlin source for the first time
How to use the link_to method
How to study Java Silver SE 8
How to use the include? method
How to use the form_with method
How to specify validation for time_field
Technical causes and countermeasures for the points I was addicted to with the first Android app & Kotlin
How to install JMeter for Mac
How to find the average angle
How to use the wrapper class
How to get the contents of Map using for statement Memorandum
[Rails] How to change the page title of the browser for each page
How to run a Kotlin Coroutine sample from the command line
How to add the delete function
[For beginners] How to get the Ruby delayed railway line name
How to check for the contents of a java fixed-length string
A memo when you want to clear the time part of the calendar
Glassfish tuning list that I want to keep for the time being
[Java] How to get the current date and time and specify the display format
[First Java] Make something that works with Intellij for the time being
How to switch the display of the header menu for each transition page
(For beginners) [Rails] Time saving tech! How to install and use slim
How to compare only the time with Rails (from what time to what time, something like)
[Socket communication (Java)] Impressions of implementing Socket communication in practice for the first time
Programming for the first time in my life Java 1st Hello World
How to implement the email authentication function at the time of user registration
[Rails] How to solve the time lag of created_at after save method
Kotlin Class part.2 to send to Java developers
How to use binding.pry for view files
[Java] How to use the File class
How to delete the wrong migration file
How to install Play Framework 2.6 for Mac
[Java] How to use the hasNext function
How to put out the error bundling