Common android music player operations

/* Variable Declaration */private ImageButton playBtn = null; // play and pause private ImageButton latestBtn = null; // The last private ImageButton nextButton = null; // The next private ImageButton forwardBtn = null; // fast forward to private ImageButton rewindBtn = null; // return private TextView playtime = null; // private TextView durationTime = null; // song time private SeekBar seekbar = null; // song progress private Handler handler = null; // used for the progress bar private Handler fHandler = null; // used for fast-forward private int currentPosition; // current playback position/* obtain the data transmitted from the list */@ Overrideprotected void onCreate (Bundle savedInstanceState) {super. onCreate (savedInstanceState); setContentView (R. layout. play); Intent intent = this. getIntent (); Bundle bundle = intent. getExtras (); _ ids = bundle. getIntArray ("_ ids"); // obtain the array position = bundle for saving the music file _ ID. getInt ("position"); // obtain the number of the music to be played, which indicates the number of the music to be played. // The code is incomplete, see the following code}/* initialization control */playtime = (TextView) findViewById (R. id. playtime); // display the played time durationTime = (TextView) findViewById (R. id. duration); // display the total time playBtn = (ImageButton) findViewById (R. id. playBtn); // the start and pause buttons latestBtn = (ImageButton) findViewById (R. id. latestBtn); // play the last button nextButton = (ImageButton) findViewById (R. id. nextBtn); // play the next button forwardBtn = (ImageButton) findViewById (R. id. forwardBtn); // rewindBtn = (ImageButton) findViewById (R. id. rewindBtn); // the return button seekbar = (SeekBar) findViewById (R. id. seekbar); // playback progress bar/* defines the callback function of each control */playBtn. setOnClickListener (new View. onClickListener () {// callback @ Overridepublic void onClick (View v) {if (mp. isPlaying () {// pause (); playBtn if playing is in progress. setBackgroundResource (R. drawable. play_selecor); // change the key status icon} else {// resume play () If no playback is available; playBtn. setBackgroundResource (R. drawable. pause_selecor); // change the button status icon }}); latestBtn. setOnClickListener (new View. onClickListener () {// callback @ Overridepublic void onClick (View v) {int num = _ ids when you click the "Last play" button. length; // get the number of music if (position = 0) {// if it is already the first, play the last position = num-1 ;} else {// otherwise, the previous position-= 1;} int pos = _ ids [position]; // get the _ IDsetup () of the music to be played (); // prepare for playing play (); // start playing}); nextButton. setOnClickListener (new View. onClickListener () {// when you click "play next", the callback @ Overridepublic void onClick (View v) {int num = _ ids. length; // obtain the number of music if (position = num-1) {// if it is the last one, play the first position = 0;} else {position + = 1; // otherwise, play the next one} int pos = _ ids [position]; // get the _ IDsetup () of the music to be played; // prepare for playing play (); // start playing}); forwardBtn. setOnTouchListener (new OnTouchListener () {// callback @ Overridepublic boolean onTouch (View v, MotionEvent event) {switch (event. getAction () {case MotionEvent. ACTION_DOWN: fHandler. post (forward); // use the handler object to update the progress bar mp. pause (); // when you click the quick forward button, the music is paused for break; case MotionEvent. ACTION_UP: fHandler. removeCallbacks (forward); mp. start (); // when the quickforward button is released, the playBtn will resume playing. setBackgroundResource (R. drawable. pause_selecor); break;} return false ;}}); rewindBtn. setOnTouchListener (new OnTouchListener () {// callback @ Overridepublic boolean onTouch (View v, MotionEvent event) {switch (event. getAction () {case MotionEvent. ACTION_DOWN: fHandler. post (rewind); mp. pause (); // when the quick return button is clicked, the break of the music is temporarily paused; case MotionEvent. ACTION_UP: fHandler. removeCallbacks (rewind); mp. start (); // when the quick return button is released, the playBtn of the music will be resumed for the moment. setBackgroundResource (R. drawable. pause_selecor); break;} return false ;}}); seekbar. setOnSeekBarChangeListener (new OnSeekBarChangeListener () {@ Overridepublic void onStopTrackingTouch (SeekBar seekBar) {mp. start (); // when you stop dragging the progress bar, the music starts to play.} @ Overridepublic void onStartTrackingTouch (SeekBar seekBar) {mp. pause (); // when you start dragging the progress bar, the music is paused.} @ Overridepublic void onProgressChanged (SeekBar seekBar, int progress, boolean fromUser) {if (fromUser) {mp. seekTo (progress); // when the progress bar value changes, the music player starts playing from the new position }}});