Android the next day (the composition structure of the project)

1:SRC Folder Analysis:

HelloWorld
----src (source folder)
Mainactivity: Main interface class
----Gen (automatically generated source folder)
R.java: Corresponding res folder
The following three internal classes are also included
-----drawble: Corresponding picture resources
-----Layout: Layouts
-----Strings: String Constants

/**
*mainactivity
* Application of the main interface class
* Main interface: Click the app icon to start the interface
* Inherit one of the four components activity
*/
public class Mainactivity extends Activity {

/**
* Method of rewriting
* OnCreate: Called automatically when the current class object is created (automatically called by the system)----callback method
* Callback method: Not our own call, is the system under certain conditions of automatic invocation, the basic start with On, OnXXX ()
* These methods we do not need to call, generally just go to rewrite the method
*/
@Override
protected void OnCreate (Bundle savedinstancestate) {
Call the parent class to do some default initialization work
Super.oncreate (savedinstancestate);
Set content view: Sets the content view to display for the window
Specifies the variable that the layout file corresponds to in R, and the load layout file is eventually displayed in a new window
The R class corresponds to the res file, and the class contains some static constants
Setcontentview (R.layout.activity_main);
}
}

2:bin folder

Apply the compiled file location (compile: Run Android aplication)

1). APK----contains the app's. apk files and other files-----The APK file does not contain the jar package, because the phone contains the relevant jar package

2): Classes.dex: Files generated after multiple. class files are compressed and packaged

3:libs file

Third-party jar package storage Path

4:res folder (Resource folder)

DRAWBLE--XX: Picture Folder
In order to adapt to different resolutions of the mobile phone
Layout: Layouts file for interface
Functions similar to HTML
Values: Constants Folder
String.xml: Contains a fixed string that is referenced in the layout: @String/name

Android the next day (the composition structure of the project)