Start learning Android development
Android development is a promising direction. Employers need programmers, and they are willing to pay. A lot of learning materials are available for beginners, and a strong community of experienced colleagues will always help with advice. You can learn on your own, but in order to simplify and speed up the process, it is better to ask the teachers for help and start with courses.
Where to start learning Android development – 1The learning path may differ depending on the tasks and background of the novice developer. Next, we will describe the basic knowledge and skills that will be needed in any case.
Basic knowledge of HTML and CSS
Learn the syntax of languages and terminology in order to correctly formulate questions and quickly search for answers. For example, it is more efficient to search in Google not for rounding the corners of a button, but for cornerRadius – the search engine will return more relevant answers.
It is a markup language that does not contain logic or algorithms and is designed for convenient data storage. It is worth learning it to lay out the user interface, set the location of buttons and text fields, and other elements of the application. XML allows the use of multilingualism; strings in different languages are written to XML files.
How HTTP and REST work
These are protocols for the interaction of applications with the outside world – other applications and services, for example, servers on the Internet. You need to master them in order to understand how the application interacts with other services and receives information from them.
Difference between programming languages. The computer does not distinguish what the program was written in – it executes machine codes. Programming languages were created for developers. They have a lot in common – almost all of them have functions, variables, classes, arrays. If you know how to use them in one language, you can switch to another if necessary. The language must be chosen for solving a specific problem, for example, for mobile development, the standard is Java.
General principles of development. To write understandable code that can be read by colleagues in large shared projects, you need to learn:
how to name functions and variables;
split the program text into files;
place hyphens and spaces.
It will not be possible to master everything at once during training, the skills will come with practice and will be constantly improved.
The basics of object-oriented programming. One of the main ideas of Java development, which is as follows. All objects or phenomena of the real world can be represented in the program as a set of their properties and performed actions. It is easier to develop a program when you understand: an application is an object, any window in it is an object, properties are height, width and background color, methods are drawing an image, adding elements.
Git and Github. Git allows you to view the history of the project, all changes, who made them and when. An error can be detected in the system and rolled back. Github is needed for complex projects that several developers are working on at the same time. When one of the developers uploads the code, the whole team can review and edit it. Moreover, it is possible to work even on the same piece of code in parallel, without interfering with the work of another developer.
Explore the Android environment
Application graphic elements. When creating an application interface, you do not need to write code from scratch, it is enough to use ready-made blocks – View. There are different types of blocks:
to display text;
to display images;
to place other items on the screen.
For the first applications, you will have enough ready-made blocks, in the future you will learn how to develop your own.
Android file system. You need to master it in order to optimize the operation of the application and teach it to start every time not from scratch, but to maintain its state between restarts. The file system also allows you to exchange data with other applications, for example, upload photos from the gallery.
The life cycle of an Android application. When the user works with your application, a call may come in, an SMS may come, or another application will display a notification over the window. For such cases, you need to register the behavior of the program, for example, minimize the window, pause, save the current state or decrease the sound volume. If you do not customize the application lifecycle, it will be inconvenient to use.
Android technology solutions. Many applications perform the same actions, such as requesting information on the Internet, performing searches, or storing bulk data. In order not to write code for these actions from scratch, learn to use libraries – typical solutions. These are pieces of code that work well and can be inserted into your application.
Navigation between screens. Most applications have multiple screens. In order for the user to navigate between them, minimize or close, you need to develop a navigation system and write an algorithm of actions for each navigation method.