"Qianfeng-android-day01-" the foundation of the history and Environment of Android:

1. Data type: Collection

2.io

3. Multithreading

1. Whether the method can be called by multiple threads

4. Network:

1.http protocol

2. Mqtt for Instant Messaging protocol
3.webservice

5. Data analysis

XML WebService

JSON character set Unicode Utf-8

6. The relationship between the operating system's processes and threads

The entry function for threads in Java is the run function
Threads are run in parallel

6.java Object-oriented =java code reuse

7. Non-computer majors look at these books
Principles of computer 2.linux operating system Principle 3. Compiling principle 4. Software Engineering Star Moon myth

Linux Open source OS linux tvals git c

8. Frequent access to open source code

Four-tier architecture for 9.Android operating systems

First Floor: Application

Second Layer: Frame layer

Layer Three: JNI layer (Android runtime layer)

Layer Fourth: Linux kernel

1.java virtual machine and davilk virtual machine differences

1.davilk virtual machine is a register-based Java is a stack-based

2. The latest Android7.0 inside the Davilk virtual machine saves the native code of the Java method, which is translated at the time of installation

The difference between Java programs and Android programs

Java Virtual machine:

1. Translating Java files into class files

2. Start the Java Virtual machine load class and start execution from the main class

Davilk virtual Machines

1. Use the Javac tool to translate Java files into class files

2. Package all the class files as Dex files

The 3.davilk virtual machine is responsible for interpreting the bytecode contained in the Dex file

Android

Key knowledge

Four Components activity service broadcast ContentProvider

UI controls

Multithreading

Network access (HTTP protocol)

Resource Management

Animation

Time distribution

System Services

Screen fit

Android App Essentials

I. Information that the application must contain

1. First start-up interface

2. Application Name

3. Icons

4. Application Version number

Two: The resources needed to generate an app installation file (apk file)

1.java source files (own business logic)

2. Application manifest configuration file Androidmanifest.xml

3. Application icon

4. Resource files (icons, layout files, files that cannot be compiled, string files,)

5. Index file of the resource file R.java file (must be generated with the build tool)

Androidmanifest.xml

<?xml version= "1.0" encoding= "Utf-8"?>

<manifest
Application Package Name

Package= "Com.qianfeng.helloworld"
Name space
Xmlns:android= "Http://schemas.android.com/apk/res/android" >

Start to describe the configuration of the application

<application
The name of the application
Android:label= "HelloWorld"
Icon of the application
android:icon= "@drawable/weixin"
>


<activity android:name= ". Helloactivity ">

<intent-filter>

<action android:name= "Android.intent.action.MAIN"/>
<category android:name= "Android.intent.category.LAUNCHER"/>
</intent-filter>

</activity>

</application>

</man

"Qianfeng-android-day01-" the foundation of the history and Environment of Android: