how to play multiple video from sdcard

I have done coding to play video from sdcard ... it run fine but when i increased the number of videos it wil not work ... 

 File SDCardRoot = Environment.getExternalStorageDirectory();
                        File file = null;
                      
                        file = new File(SDCardRoot,"video.m4v");
                        
                        FileInputStream fileInputStream = new FileInputStream(file);
                        mMediaPlayer.setDataSource(fileInputStream.getFD());         
                        fileInputStream.close();

but i want to play multiple video but ....

it is not working ...

Thanks in advance...