File file=newFile(Environment.getExternalStorageDirectory(), name);

                try{

                    FileOutputStream  fos=newFileOutputStream(file);

                    fos.write(content.getBytes());

                    fos.close();

                      Toast.makeText(getApplicationContext(),"保存成功", 200).show();

                 }catch(Exception e) {

                      Toast.makeText(getApplicationContext(),"保存失敗", 200).show();

                     e.printStackTrace();

                 }

File file = new File(Environment.getExternalStorageDirectory(), name);

             try {

                 FileInputStream fis= new FileInputStream(file);

                 BufferedReader br =new BufferedReader(new InputStreamReader(fis));

                 //讀取文檔的數(shù)據(jù)

                 String content =br.readLine();

                 //拆分字符串

                 String [] str =content.split("=");

              //顯示數(shù)據(jù)

                 if(!content.isEmpty()){

                    et_name.setText(str[0]);

                    et_password.setText(str[1]);

                 }

             } catch (Exception e) {       

                 e.printStackTrace();

             }    

          }

<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE”/>

<uses-permission android:name="android.permission.MOUNT_UNMOUNT_FILESYSTEMS"/>