The beginners guide to android

A beginner guide to Android build files

Development is not easy and build system can be more confusing. I feel your pain.

The android project structure is not easy to adapt at first glance, especially if you have a multi-module project. This article aims to simplify an important aspect of Android project structure: build files. Is this article for you? Will it add value? Depends on:

• If you are a new Android developer, buckle your belt. It surely will help
• If you are one of those developers who click sync now whenever Android studio asks you; you definitely need this article

• If you are experienced developer and comfortable with Android build files and know in and out, read for proofreading and revising. I will appreciate leaving a note on how to improve this article
• You do not want to waste time on Social media and do not know what else to do

Section 1 Gradle

First thing first, Android Studio supports Gradle as its build automation system. Gradle is a nice tool and a detailed explanation is out of the scope of this article. You need to read books for that. Believe me, reading is good. For beginners, I will explain in a very basic way what it is. Experienced can skip this section.

If you are a software developer, you write code. You do not send your code to users. Any software you write in any platform, you need to perform some steps before you can release OR to convert in the form you can share with your users. In Java, it is a jar, Windows exe, Mac dmg, Android apk and so on. To convert your code into the required output, you follow certain steps. The steps can vary depending on the platform you work with. For example compilation, code stripping, deleting unused code, optimizing code, can be few steps before the final result.

Now, these steps are finite and sequential. Let’s say you can run each step with a command.

• Add time logging in each method
• Compile code
• Strip unused code
• ……

Either you can run these commands manually OR ask a computer to do for you. Whenever something is algorithmic in nature, automation is the right way to go. Gradle, my friend is just this, a tool/script to run the commands required to build the final binary (apk in Android).

Note:The code you write does not execute as it is. Indirectly you convert it by adding/stripping/changing/ optimizing before you release binary(final format).

Dependency

Your Android project does not suffice on its own. First of all, it is dependent on the Android classes and mostly Android support classes. 99% your project also depends on 3rd party libraries. It can be for HTTP, image loading, database, some native processing, and so-on. These are called dependencies: Well written utilities can be reused by other projects. The format of these dependencies also depends on the framework you are programming in. It can be an Android aar, Java Jar, Ruby gem and so on.

There are again two ways to use dependency:

First is manual and Second is automation. Manually you can take the dependency output file and drop in your project and then add to classpath so your tools can find them and your classes can use them. Every time a new version is released, you need to keep an eye. Not more than a few years back, developers were supposed to do it. It is just too tedious to do all this. Why waste time on duplicate and boring efforts when we can watch Star Wars 7th time. After all, we are developers.

Second and Better way is to ask the computer to do all this repetitive and boring job for us. We can tell the computer program what all dependencies we need and it will obey our command. It will fetch those output files and place it in the exact position required. No more errors and no more boring work. We can continue our interesting Gossip over coffee.

Summary Section 1

To convert your raw code into something executable, you need a few other libraries (dependencies) and you need to perform certain operations. The operations are also called tasks and they vary depending on the framework you work with. Automating this process of fetching dependencies and running required tasks to generate the executable is called automated build system. Gradle is just that.

Источник

Как начать программировать под Android? Пошаговый план

В этой статье мы рассмотрим, как начать программировать под Android. Пошаговый план с ссылками на ресурсы, курсы и книги и типичные вопросы, которые задают на собеседованиях на позицию junior Android-разработчика. Ну а если вы хотите быстро за 12 занятий вникнуть в азы Android — то приглашаю на практический онлайн-интенсив где вы с наставником разработаете собственный проект.

Итак, вы решили начать программировать под операционную систему Android. Для начала, вам нужно изучить язык программирования. В мире Android на момент написания статьи (март 2020) года используются как Java, так и Kotlin, однако второй официально рекомендован компанией Google и набирает всё большую популярность, так что, если вы не знаете ни одного языка программирования — то можете изучать Kotlin, если же вы уже знаете какой-либо объектно-ориентированный язык программирования, то изучить Java или Kotlin для вас не составит труда. На рынке тренд идет в сторону Kotlin.

Изучаем язык

Kotlin

Чтобы освоить Kotlin, вам могут пригодиться, следующие ресурсы:

• Try Kotlin — набор примеров и заданий по Kotlin cразу с консолью, в которой можно ввести код и проверить
• Kotlin Bootcamp for Programmers — туториал от Google
• Android Kotlin Fundamentals Course — набор мини-курсов для быстрого старта в Android — разработке
• Книга «Kotlin. Программирование для профессионалов» — Книга Джоша Скина и Дэвида Гринхола основана на популярном курсе Kotlin Essentials от Big Nerd Ranch. Яркие и полезные примеры, четкие объяснения ключевых концепций и основополагающих API не только знакомят с языком Kotlin, но и учат эффективно использовать его возможности
• Kotlin Bootcamp for Programmers — хороший видеокурс, объясняющий основы программирования на Kotlin

Чтобы освоить Java, вам могут пригодиться, следующие ресурсы:

• Изучаем Java Сьерра Кэти, Бэйтс Берт — эта книга не только научит вас теории языка Java и объектно-ориентированного программирования, она сделает вас программистом. В ее основу положен уникальный метод обучения на практике. В отличие от классических учебников информация дается не в текстовом, а в визуальном представлении.
• Become a Java Developer — курс от Udacity, который поможет вам изучить Java
• Джошуа Блох: Java. Эффективное программирование — эта книга является классикой для Java-программистов. Для новичков может быть несколько сложновата, но постарайтесь прочитать ее хотя бы половину и вернитесь к ней через годик, все сразу станет на свои места. Кстати, многие вопросы на собеседовании по Java взяты именно отсюда, так что не ленитесь, почитайте.
• Java. Библиотека профессионала. Том 1. Основы | Хорстманн Кей С. — Эта книга давно уже признана авторитетным, исчерпывающим руководством и практическим справочным пособием для опытных программистов, стремящихся писать на Java надежный код для реальных приложений. Быстро освоить основной синтаксис Java, опираясь на имеющийся опыт и знания в программировании.

Изучаем Android SDK

Как только вы освоили базовый синтаксис и поняли базовые концепции, переходите к изучению Android SDK, параллельно читая перечисленные выше книги. Изучение Android SDK вы можете начать с таких ресурсов как:

• Android Kotlin Fundamentals — набор туториалов для начинающих Android-разработчиков от Google на языке программирования Kotlin. Из курса вы узнаете об основных компонентах Android SDK, таких как Activity, Intent, BroadcastReceiver и других.
• Become an Android Developer — курс на Udacity, где за 6 месяцев вам расскажут от том как разрабатывать мобильные приложения под Android
• Школа мобильной разработки — набор лекций об устройстве Android от Яндекс. Часть материала немного устарела, но даже сейчас будет очень полезна как начинающим, так и уже более-менее опытным разработчикам.
• Android Programming: The Big Nerd Ranch Guide — достаточно понятная книга для новичков, чтобы понять программирование под Android OS
• The Busy Coder’s Guide to Android Development — книга, которая уже, наверное стала классикой для Android — программистов, один из самых полных источников знаний по Android OS

Это далеко не полный список, материалов огромное количество, но изучив вышеперечисленные ресурсы, вам с запасом хватит знаний для программирования под Android. Главное — не забывайте ежедневно практиковаться, общаться с наставником или ментором чтобы быстрее понимать свои ошибки и учиться на них.

Изучаем популярные библиотеки

Итак, вы неплохо знаете синтаксис языка, понимаете ООП, умеете применять наследование там где оно нужно и ваши приложения более-менее работают. Возможно, еще без применения архитектуры (MVP/MVVM/VIPER/RIBs) и без навороченных библиотек или фрэймворков. Самое время изучить и их.

В этом разделе я приведу список наиболее популярных библиотек, который используются в большинстве Android — проектов. Изучив их, вы смело сможете претендовать на звание junior или даже middle — разработчика.

Для многопоточного программирования

• RxJava 2 — видеокурс введение в RxJava на Stepic или бесплатный базовый курс по RxJava
• Kotlin Coroutines — набор туториалов и документация по корутинам от Jet Brains
• Основы работы с WorkManager— туториал по работе с WorkManager
• Advanced Coroutines with Kotlin Flow and LiveData — туториал от Google как рабоать с корутинами и LiveData

Библиотеки для Dependency injection

Библиотеки для сетевого взаимодействия

• Retrofit — пошаговый туториал, где вы создадите приложение для поиска фильмов

Библиотеки для обработки изображений

Библиотеки для работы с Json

Библиотеки для хранения данных

• Room — мини-курс, который поможет понять основы Room + LiveData
• Realm

Изучив, материалы из этого списка вы уверенно сможете претендовать на роль джуниор-разработчика, а в следующем посте мы рассмотрим наиболее часто задаваемые вопросы на собеседованиях. А прямо сейчас приглашаю вас на онлайн-интенсив по разработке

Источник

The 12 Best Android Tutorials for First-Time App Developers

This article was updated in January 2017.

Learn more about the official Android IDE with our screencasts A Tour of the Official Android IDE – Android Studio screencast.

When there is so much information and you are a first-time Android developer, it’s easy to get confused about where to start. To make it easy for you and with no illusions that this list of Android tutorials is the best or complete, here are 12 Android tutorials to start with.

Not all the tutorials and their content are strictly beginner beginner focussed. Some of them start out for beginners and then delve into more advanced topics. So if you can’t follow everything in every single tutorial, don’t get desperate or frustrated.

If you encounter a hurdle, just spend more time with the tutorial, reading it a couple of times if necessary. If you are still not on friendly terms with it, there is no drama – just move forward and revisit it later.

Building Your First App

Naturally, we start the list with a tutorial from Google, the creators of Android. The ‘Building Your First App‘ tutorial starts from the very beginning and it’s suitable for absolute beginners. If you have no programming knowledge whatsoever, don’t expect to be able to handle the tutorial but if you have some programming background, it’s easy.

The tutorial has several ‘Best Practice’ sections at the end. This is good because all the important content about the topic in one place and you just have to read it.

Android Development – Tutorial

The reason this tutorial is near the top is that it’s very up-to-date (based on Android 7.0, the latest Android version as of today).

This tutorial has more topics and information than the tutorial from Google, so if you are looking for an in-depth tutorial, this is one the.

It’s not an easy or quick tutorial. If you want to get the most from it, you will need quite a lot of time to read it from start to finish. It can be a great source if you need to consult a given topic in detail.

Video Tutorials Series

I find video tutorials less useful (except when they teach design, animation, or any other visual topic) but for many people they are the preferred way of learning. If you belong to this group, you will love this series of video tutorials.

It’s a comprehensive series of video tutorials ranging from under 5 to 15 minutes in length. Similarly to the previous two tutorials, this series covers everything from absolute beginner level to advanced topics. It’s not uptodate but I couldn’t find a decent video tutorial about a more recent Android version.

An Android Tutorial/Book

It might be old-school, but for me the best way to get a complete idea about something is by reading a book about it. In a book, everything is organized logically, pages are numbered and keep their layout and there is enough text to explain the and code/graphics. The first two tutorials in this list are book-like but if you want something more authentic you could print them. Even better, a pdf tutorial, like this one, is a much better option. Similarly to the previous resource, this one might not be very up to date but it does cover the major principles of Android programming.

This is one more general tutorial that covers Android development from beginner level to advanced.

Game Development Series

If you have some knowledge about Android but you want to delve into games development, this series of video tutorials is a great start. The series starts with the very basics of Android (and Eclipse) but my personal feeling is that if you are a total stranger to Android, the journey will be too hard. Again, this tutorial isn’t about the latest Android version but it does give a solid foundation about Android programming and I couldn’t find a more current one.

From what I saw, the series mentions general Android as well, not only game development. If you don’t know Android basics, my advice is to first read some of the general Android tutorials and then move to specialized topics, such as game development.

Better User Interfaces with the Android Action Bar

After you have had enough of general Android tutorials, let’s move to tutorials for common tasks. For some of these topics you can find information in the general tutorials as well but if you want more detail, this is for you. The first tutorial is about how to build Better User Interfaces with the Android Action Bar.

In this tutorial you will learn how to set up the action bar, how to add actions, how to split, hide, and overlay it, as well as how to add navigation. You will also learn about action bar interactivity, such as how to handle clicks on its items and to use action views.

Learning to Parse XML Data in Your Android App

While you could write Android applications that do not involve any data input, often you will need external data. In such cases you need to know how to handle this data. XML can help you a lot and this is why I’ve included a tutorial on how to Parse XML Data in Your Android App.

This tutorial leads you step by step in the world of XML parsing. It also helps you create a parser that will look like the one shown in the next screenshot.

Android 101 for iOS Developers

With the huge popularity of Android, even die-hard iOS developers are likely to consider switching or at least expanding to it. If you are an iOS developer, you are lucky because you are not new to mobile development as a whole. Of course, you could read the general Android tutorials I listed earlier but especially for you, here is a better tutorial. Unfortunately, some of the info in this tutorial might be outdated but with the rapid development of mobile programming technologies this is inevitable. You might want to check a more recent tutorial on the same topic but it isn’t as detailed as the first one.

This tutorial is great because it summarizes the differences between iOS development and Android development, thus making the change easier for you. You might need separate reading on some of the points it mentions but it’s a great tutorial without being overly detailed.

Scheduling Background Tasks in Android

This topic is a bit advanced but since it’s not too difficult and it’s useful, it makes sense to include it on the list. The ‘Background tasks in Android‘ tutorial discusses the types of alarms in Android and how to set them.

Android Adventures – Getting Started With Android Studio

I don’t think Android Studio is the most popular method to develop Android apps but since it (supposedly) makes Android development easier, here is a tutorial about Android Studio.

Even if you already use other Android development tools and you wouldn’t change them, it still makes sense to read what Android studio can offer.

The tutorial is a pretty detailed one – it starts with how to install Android Studio, how to create a new project, how to add functionality to it, how to run it, etc. The tutorial isn’t hard to read but if you have no prior Android knowledge, you might not be able to understand everything.

Localizing Android Apps

Android applications are popular all over the world. Your users speak different human languages, which means if you want to reach them, you need to think about localizing your Android apps. This tutorial explains it all.

Getting Started with Android Library Projects

At some point in your Android development career you will get tired of having to re-invent the wheel all the time and you will appreciate the advantages of reusable code. If you are already there, you will certainly want to know more about reusable code. In this case this tutorial will help you get started as quickly as possible.

The ‘Getting Started with Android Library Projects’ tutorial is a bit longer because it’s a three-part series. The first part warms you up with some basic concepts, while the other two delve into more detail about how and when to use Android Library Projects.

Conclusion

I can’t promise that after reading all the tutorials on this list you will become a top Android developer but they are a great start.

Most of these tutorials are for beginners but I am sure that even experienced Android developers will have something new to learn, or find better ways of doing a task they’ve been doing for ages. So, if you have a spare minute, check the tutorials, learn something new and let us know your favorite tutorials.

Learn more about the official Android IDE with our screencasts A Tour of the Official Android IDE – Android Studio screencast.

Источник