Android Development Series (vii): Storing files in SDcard

In general our mobile app default storage space is the memory of the phone, but for larger files such as video, audio, we can store it in SDcard:

Next, the code is implemented to store the files in SDcard (only the core code is implemented).

First, because we want to store in SDcard, we need to provide SDcard permissions:

To add permissions in Androidmanifest.xml:

<!--Create and delete file permissions in SDcard--><uses-permission android:name= "Android.permission.MOUNT_FORMAT_FILESYSTEMS"/ ><!--Write Data permissions to SDcard--><uses-permission android:name= "Android.permission.WRITE_EXTERNAL_STORAGE"/>

Then, add a method in the Fileservice.java:

public void Savetosdcard (String filename,string content) throws Exception{//environment.getexternalstoragedirectory ( ) function is to obtain the path of the SDcard file File = new file (environment.getexternalstoragedirectory (), filename);//Open the output stream FileOutputStream OutStream = new FileOutputStream (file);//write Content Outstream.write (Content.getbytes ()); Outstream.close ();}

The point is: environment.getexternalstoragedirectory () function

Finally, after clicking the "Save" button, we call the button's OnClick () method, which is added in this method:

New a Fileservice object, Getapplicationcontext () returns the context of the application, the life cycle is the entire application, and the application destroys it to destroy fileservice service = new Fileservice ( Getapplicationcontext ()); try {        //To determine if the sdcard exists, and can read and write,//environment.getexternalstoragestate () Gets the current state://environment.media_ Mounted represents the state of SDcard: Presence Sdcardif (Environment.getexternalstoragestate (). Equals (environment.media_mounted)) { Service.savetosdcard (filename, content); Call the Save () method to save the file Toast.maketext (Getapplicationcontext (), r.string.success, 1). Show (); Call a Toast to render a "save complete" message}else{toast.maketext (Getapplicationcontext (), R.string.sdcarderror, 1). Show ();// Call a Toast to render a "sdcard non-existent or write-protected" message}} catch (Exception e) {toast.maketext (Getapplicationcontext (), R.string.fail, 1). Show (); Call Toast object to render a "save failed" message E.printstacktrace ();}

Android Development Series (vii): Store files in SDcard