Android Learning note 39--using raw resources

Raw Resources

There is no type file in Android that specifically provides administrative support, which is called the original resource. For example: sound resources ...

Android Raw Resource storage location:

The 1.res/raw,android SDK processes the original resources in the directory and generates a unique index in the R manifest

2./assets/, the resources under this directory are more thorough primitive resources. Android uses Assetmanager to manage raw resources in this directory

Note: The unique indexes generated by the original resource through the SDK are used in the same way as other resources are used. eg:r.raw.filename/@raw. FileName

Assetmanager is a manager class that specializes in managing raw resources under the/assets/directory, which provides the following common ways to access assets resources:

1.InputStream Open (String filename): Gets the input stream corresponding to the original resource according to the file name

2.AssetFileDescriptor openfd (String fileName): Obtaining the original resource according to the file name the Assetfiledescriptor.assetfiledescriptor represents a description of the original resource that the application can use to obtain the original resource.

Examples: How Res/raw and/assets/are used:

Operation Steps:

1. Put different audio files in raw and assets directories respectively

2. Start with code processing ....

Layout file = = "<linearlayout xmlns:android=" http://schemas.android.com/apk/res/android "xmlns:tools="/http Schemas.android.com/tools "android:layout_width=" match_parent "android:layout_height=" Match_parent "Android:gravi Ty= "Center_horizontal" android:orientation= "Horizontal" tools:context= ". Mainactivity "> <button android:id=" @+id/btnraw "android:layout_width=" Wrap_content "Android : layout_height= "wrap_content" android:text= "raw"/> <button android:id= "@+id/btnassets" Android Oid:layout_width= "Wrap_content" android:layout_height= "wrap_content" android:text= "assets"/> &lt ; Button android:id= "@+id/btnstop" android:layout_width= "wrap_content" android:layout_height= "Wrap_cont Ent "android:text=" Stop "/></linearlayout> code implementation = =" Package Com.example.myoriginalresources;import Java.io.I Oexception;import Android.media.mediaplayer;import android.os.bundle;import Android.App. Activity;import Android.content.res.assetfiledescriptor;import Android.content.res.assetmanager;import Android.view.menu;import Android.view.view;import Android.view.view.onclicklistener;import Android.widget.Button; public class Mainactivity extends activity{mediaplayer Mediaraw = null; MediaPlayer mediaassets = null, @Overrideprotected void OnCreate (Bundle savedinstancestate) {super.oncreate ( Savedinstancestate); Setcontentview (r.layout.activity_main); Mediaraw = Mediaplayer.create (this, R.RAW.RAWQ); Assetmanager am = getassets (); try{//gets the assetfiledescriptorassetfiledescriptor afd = AM.OPENFD ("Assets.mp3") corresponding to the specified file; Mediaassets = new MediaPlayer ();//use MediaPlayer to load the specified MP3 file Mediaassets.setdatasource (afd.getfiledescriptor ()); Mediaassets.prepare ();} catch (IOException e) {e.printstacktrace ();} Button Btnraw = (button) This.findviewbyid (R.id.btnraw); Button btnassets = (button) This.findviewbyid (r.id.btnassets); Button Btnstop = (button) This.findviewbyid (r.id.btnstop); Btnraw.setonclicklistener (new ButtonClick ()); Btnassets.setonclicklistener (new ButtonClick ()); Btnstop.setonclicklistener (new ButtonClick ());} Class ButtonClick implements onclicklistener{@Overridepublic void OnClick (View v) {switch (V.getid ()) {case R.id.btnraw: Mediaraw.start (); break;case R.id.btnassets:mediaassets.start (); break;case r.id.btnstop:mediaassets.stop (); Mediaraw.stop (); finish (); break;}}} @Overridepublic boolean Oncreateoptionsmenu (Menu menu) {//Inflate the menu; This adds items to the action Bar if it is pre Sent.getmenuinflater (). Inflate (R.menu.main, menu); return true;}}

　　

Android Learning note 39--using raw resources