Practical Android skills: Summary of Android Learning Resources

If you want to understand a technology, master a technology, or become a master or expert, learning is an inevitable way. In my opinion, there are two factors that determine the learning efficiency and Achievements: one is the learning method and the ability to comprehend, and the other is the need for a set of good learning resources. The same is true for learning Android development. This document will summarize some valuable learning resources in Android learning.

1. Android SDK documents ents

This is very easy to obtain. You can refer to the official website or the locally installed SDK, because Android SDK must be available for Android development, all sdks contain documents. I suggest reading the official website, because it is always up-to-date. Previously, the official website was harmonious and could not be viewed, but it could be viewed completely later, and the server responded quickly and smoothly.

Why should I read the official documentation? First, it is an official document. In other words, it is the most authoritative document, so you can rest assured that you do not have to worry about whether it is true or not. Second, it is also the most important. The content in this document is very rich, from how to download and install the SDK, to the basic experience of helloworld, to basic development knowledge, to the index of the entire sdk api, and to some useful article resources. If you can read all the SDK documentation carefully, you are already a mature Android developer.

It is recommended that you read the content in the dev guide column first, which will help you understand some basic public knowledge used by all android development projects. Then you can go to the references column to find the detailed usage method of the corresponding API. This does not need to see the last one from the first one, but should be used like the dictionary, that is, when you want to use an API or do not know how to use an API, you can check the references again. Here, you must learn how to use search. There is a search box in the upper-right corner of the references column to help you quickly locate a class. When a class is opened, you also need to use Ctrl + F to search for the methods or constants you need, and make good use of the search can save a lot of time. Then, you should take a look at the resources bar from time to time. The documents here are worth reading carefully, which can help you become a master or make your program more robust.

2. API demo

As its name implies, the purpose of this sample is to show you how to use the android API. Although it is not comprehensive or in-depth, however, for many common APIs, such as activity, dialog, view, and graphics, code is provided for reference. The most important thing is that it is not a document, it teaches you how to use it, but a very direct code. In many cases, you can copy it directly.

3. Other samples in SDK

For example, notepad, Snake, spinner, and spinnertest. These samples do not show how to use APIs in API demos. They focus on one aspect. For example, notepad can fully learn how to use contentprovider; snake can fully learn how to create custom views; and spinnertest shows how to write unittest for Android ).

In fact, in addition to documents, many things in the SDK are ignored by many people. Now, open the SDK folder immediately to see what is in it and how many things are worth looking at and studying.

4. Android source code

Needless to say, this is the best place to learn and study android. All things about Android are included, and you can easily get it for free, study it, learn it, I think this is also the biggest advantage of open-source software: You can easily obtain the source code for learning and research.

The source code of android can be learned mainly in three folders: externals, which is a third-party open-source package collection. It contains all the open-source third-party libraries used by Android, such as WebKit, opencore, OpenSSL, and so on. People who want to study them can directly kill them. The other is frameworks, which is the framework of Android, which mainly provides support for upper-layer apps, the android SDK APIs are all from here. Of course, the content in the APIS is much higher than the open APIs. If you want to customize a view or implement an advanced container, you can refer to it, or, if you want to directly study how those APIs are implemented, you can directly kill them. The last one is
Packages, which contains some system core applications and system-level providers and input methods at the app layer of Android. These applications are good examples of how to use APIs. After being customized by the manufacturer, the core applications of the system have been changed a lot. Some system software on the market is also easier to use than the native ones, however, these built-in native apps are worth researching and learning. They not only demonstrate how to correctly use various APIs, but also how to use APIs that are not open to the system, that is, Com. android. internal. * The following are core applications that focus on how to use key system packages, such as Android. telephony. *; android. provider. *; android. media. *; packageinstaller and launcher are also worth studying.

If you want to study how Android works and how the underlying layer is implemented, the following things in externals must be viewed, many of Android's frameworks layer objects are ultimately supported by third-party Libraries under externals.

If you want to write custom components, you can refer to the official components provided by frameworks, or rewrite them, or refer to the implementation method in them, for example, if your application needs a special gridview, but the official gridview cannot meet the requirements, you can consider override the gridview through inheritance, or fully refer to the implementation method of the gridview for self-implementation.

If you want to use telephone and information-related applications, phone, MMS, and telephonyprovider must be referenced. If you want to use multimedia applications, music and gallery must be referenced. If you want to do hardware-related work, camera and Bluetooth must also be referenced.

In addition, the android system pays great attention to testing. A large part of the code is specially used for testing, mainly including CTS testing and monkey testing, in addition, each application has a test application, which is also a good teaching material for learning how to write unit tests for Android.

5. Network Resources

In the Internet era, no matter what you learn or study, the network is a resource that cannot be ignored. The main methods are forums and blogs.

At present, the Forum focuses on Android with a hundred million eoeandroid. There are many blogs, and csdn also has many excellent blogs. You can search a lot.