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With the continuous development of Internet companies, there are more and more modules in product projects, and user experience requirements are getting higher and higher. It is becoming more and more difficult to achieve the purpose of fast running in small steps and rapid iteration. There is also 65535. The application of plug-in technology is born for problems such as the mutual calling of each other. If there is no plug-in technology, the applications that integrate a large number of "app" such as Meituan and Taobao may be as big as a few g.

Therefore, today's Android mobile development will not be hot-fixed, plug-in, and componentized, and more than 80% of the interviews will not pass.

Ali P8 boss stayed up until one or two in the morning, spent nearly half a month to Android hot repair framework, plug-in framework, component framework, image loading framework, network access framework, RxJava reactive programming framework, IOC dependency injection Framework, recent architecture component Jetpack and other Android third-party open source frameworks have been integrated into a set of system knowledge notes PDF, up to 1042 pages! I believe that after reading this document, you will have a deeper and more systematic understanding of these Android third-party frameworks.

Due to the excessive content of the document, in order to avoid affecting everyone's reading experience, only part of the content is shown in screenshots. The detailed and complete version of the 1042 [Android Design Idea Interpretation Open Source Framework] document collection method: like + follow, and then privately message keywords 【666】You can get a free way to receive it!

Interview questions

I went from common Android basic knowledge interview questions to Java interview questions. Then I tackled Android advanced interview questions, and broke through and learned Flutter-related hot technical interview questions (not difficult), and finally I focused on the summary of the real interview questions of this year's big factory.

Android basics

One, Activity

1. What is Activity?

2. Please describe the Activity life cycle

3. Common activity types include FragmentActivitiy, ListActivity, TabAcitivty, etc. Please describe the Activity life cycle

4. How to save the state of Activity?

5. Which methods must be executed when jumping between two activities?

6. Activity life cycle when switching between horizontal and vertical screens

7. How to set an Activity as a window style

8. How to exit Activity? How to safely exit an Application that has called multiple activities?

9. What is the difference between singletop and singletask in the four startup modes of Activity? General bookmark usage mode is singletop, so why not use singletask?

10. What is the difference between Context, Activity and Appliction in Android?

11. To transfer data between two activities, besides intent, broadcast receiver, content provider, what else?

12. What is Context?

Two, Service

1. Is the Service executed in the main thread, and can time-consuming operations be performed in the service?

2. How to bind Activity to Service and how to start its corresponding Service in Activity?

3. Please describe the life cycle of Service

4. What is IntentService? What are the advantages?

5. Talk about the relationship between Activity, Intent and Service

6. Are Service and Activity in the same thread?

7. Can I play toast in Service?

8. What is a Service and describe its life cycle. What are the methods to start the Service, what is the difference, and how to stop the Service?

9. Can the service life cycle method onstartConmand() perform network operations? How to perform network operations in service?

Third, Broadcast Receiver

1. Please describe BroadcastReceiver

2. How to register and use BroadcastReceiver in manifest and code

3. The life cycle of BroadCastReceiver

Four, ContentProvider

1. Please introduce how ContentProvider realizes data sharing

2. Please introduce the Android data storage method

3. Why use ContentProvider? What is the difference between it and sql implementation?

4. Talk about the relationship between ContentProvider, ContentResolver, ContentObserver

Five, ListView

1. How does ListView improve its efficiency?

2. How to update ListView when the ListView data set is changed

3. How does ListView implement page loading?

4. Can ListView display multiple types of items?

5. How to locate the ListView to the specified position

6. How to embed ListView in ScrollView

7. How to optimize pictures in ListView

8. How does the problem of picture misalignment in ListView occur?

9. How to refresh the data of a single item in the ListView without refreshing the data of the entire ListView?

Six, Intent

1. What types of data can be transferred when Intent transfers data?

2. The difference between Serializable and Parcelable

3. Please describe Intent and IntentFilter

Seven, Fragment

1. How to transfer values between Fragment and Activity

2. Describe the life cycle of Fragment

3. The difference between the replace and add methods of Fragment

4. How does Fragment achieve the push and pop effect similar to the Activity stack?

5. Use of Fragment in your project

6. How to switch fragement without re-instancing

Java interview questions

One, Java basics

1. What are the reference types in Java

2. What is overloading, what is rewriting, and what is the difference? )

3. The difference between String, StringBuffer and StringBuilder

4. How are the keywords final and static used

5. What are the layers of the TCP/IP protocol cluster? Which layer does TCP, IP, XMPP, HTTP belong to?

Two, design patterns in Java

1. What are the design patterns you know

2. Singleton design pattern

3. Factory design mode

4. Builder mode (Builder)

5. Adapter design pattern

6. Decoration mode (Decorator)

7. Strategy mode (strategy)

8. Observer mode (Observer)

Android Advanced

1. Android performance optimization

1. How to perform performance analysis on Android applications

2. Under what circumstances will cause memory leaks

3. How to avoid OOM exception

4. How to catch uncaught exception in Android

5. What is ANR? How to avoid and solve ANR (important)

6. What are the ways of communication between Android threads (important)

7. The difference between Devik process, linux process and thread

8. Describe the Android system architecture?

9. How do android applications limit memory? How should we reasonably use memory?

10. What is the structure of android application?

11. Please explain the difference between the permissions of the Android program and the file system permissions when running?

12. The working method and principle of Framework, how does Activity generate a view, and what is the mechanism?

13. What is the difference between multi-thread communication and multi-process communication, and how to realize each?

2. Android screen adaptation

1. What are the screen adaptation methods?

2. What are the processing techniques for screen adaptation

Three, AIDL

1. What is AIDL and how to use it

2. What is the full name of AIDL? How does it work? What types of data can be processed?

Four, event handling in Android

1. Handler mechanism

2. Event distribution mechanism

3. When the child thread sends a message to the main thread to update the UI, what else is there besides handler and AsyncTask?

4. Can a new handler be used in a child thread? why?

Five, animation in Android

1. What are the types of animations in Android? What are their characteristics and differences?

2. How to modify the Activity entry and exit animation

3. Attribute animation. For example, if a button moves from A to B, point B can still respond to click events. What is the principle?

6. The role and characteristics of ContentObserver content observer

Use of project framework

1. Introduction

2. What frameworks and platforms have been used in development

Three, which custom controls have been used

Four, custom control: the realization process of drawing a circle

Five, custom controls: the implementation process of the Ferris wheel

Sixth, custom control: the implementation process of drag-and-drop sorting GridLayout

Seven, the realization process of flow layout

8. Project process

Nine, common problems in the project

10. How does instant messaging work?

11. Six principles of design patterns

12. Third party login

13. Third-party payment

14. Analysis of common frameworks

end

Development requires a certain foundation. I started to enter the Android industry in 2008. During this period, I experienced the heyday of Android, and the so-called Android "cold." Of course, there is also an unspeakable sadness in the middle. Looking at my friends and colleagues one by one, I switched to the front end and changed industries. In fact, I had hesitated at the time, but I persisted. This epidemic is a good opportunity. The big waves wash away the sand, and the fittest survives. Wait, maybe you will be waiting for the next wave of gold.

This is some information I have accumulated over the past 10 years in this industry. If I still want to continue in this industry, or if I plan to change jobs now, I can **Private Message [Learning]** I am willing to share the information with everyone for free.
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Android learning PDF + architecture video + interview document + source code notes