android 音乐播放器关于歌词的处理

         当我们制作音乐播放器中我觉得歌词的处理是比较难的一块， 对于音乐播放和媒体控制我们可以使用MediaPlayer来搞定，它提供了媒体控制的接口，使得我们对于媒体控制来说变得比较简单。但对于显示歌词来说就比较复杂了一点，例如让歌词一个字一个字高亮、快进时控制歌词处理或者倍速播放时歌词的处理等等， 这里我想介绍简单让一行歌词高亮显示, 等这行歌词唱完，让下一行歌词高亮显示。

1. 解析歌词文件

常见的歌词文件有：.lrc 和 .txt格式, 内容格式为：[00:02.59] 飘洋过海来看你

所以我们先要去解析歌词文件, 定义一个类去保存每行解析出来的数据。

public class Lyric {public String lricString;public int sleepTime;public int timePoint;}

我们对照着 "[00:02.59] 飘洋过海来看你" 来看, lrcString保存的是"飘洋过海来看你", sleepTime保存的是这句歌词播放时间, 就是下一句歌词开始播的时间减去本句歌词播放的时间,timePoint就是将 “[00:02.59]” 时间文本解析出来转换成的秒数。

现在我们开始解析歌词文件然后将数据保存到Lyrc中

public class LrcUtils {private static List<Lyric> lyricList;/** * 读取文件 */public static List<Lyric> readLRC(File f) {try {if (f == null || !f.exists()) {lyricList = null;} else {lyricList = new Vector<Lyric>();InputStream is = new BufferedInputStream(new FileInputStream(f));BufferedReader br = new BufferedReader(new InputStreamReader(is, getCharset(f)));String strTemp = "";while ((strTemp = br.readLine()) != null) {strTemp = <span style="font-family:Arial, Helvetica, sans-serif;font-size:10px;">processLRC</span>(strTemp);}br.close();is.close();// 对歌词进行排序Collections.sort(lyricList, new Sort());// 计算每行歌词的停留时间for (int i = 0; i < lyricList.size(); i++) {Lyrc one = lyricList.get(i);if (i + 1 < lyricList.size()) {Lyric two = lyricList.get(i + 1);one.sleepTime = two.timePoint - one.timePoint;}}}} catch (Exception e) {e.printStackTrace();}return lyricList;}/** * 处理一行内容 */private static String processLRC(String text) {try {int pos1 = text.indexOf("[");int pos2 = text.indexOf("]");if (pos1 >= 0 && pos2 != -1) {Long time[] = new Long[getPossiblyTagCount(text)];time[0] = timeToLong(text.substring(pos1 + 1, pos2));if (time[0] == -1)return "";String strLineRemaining = text;int i = 1;while (pos1 >= 0 && pos2 != -1) {strLineRemaining = strLineRemaining.substring(pos2 + 1);pos1 = strLineRemaining.indexOf("[");pos2 = strLineRemaining.indexOf("]");if (pos2 != -1) {time[i] = timeToLong(strLineRemaining.substring(pos1 + 1, pos2));if (time[i] == -1)return ""; // LRCTexti++;}}Lyric tl = null;//防止有的歌词文件是这种格式：[00:01:23][00:03:02]重复歌词//就是歌词重复的放在一起，将多个时间戳放在一起，所以在解析完歌词需要排序一下。for (int j = 0; j < time.length; j++) {if (time[j] != null) {tl = new Lyric();tl.timePoint = time[j].intValue();tl.lricString = strLineRemaining;lyrcList.add(tl);}}return strLineRemaining;} elsereturn "";} catch (Exception e) {return "";}}        //获取一行中的时间标签的个数，为了防止将重复歌词放在一行上显示private static int getPossiblyTagCount(String Line) {String strCount1[] = Line.split("\\[");String strCount2[] = Line.split("\\]");if (strCount1.length == 0 && strCount2.length == 0)return 1;else if (strCount1.length > strCount2.length)return strCount1.length;elsereturn strCount2.length;}/** * 时间转换，将time格式时间转换成秒 */public static long timeToLong(String Time) {try {String[] s1 = Time.split(":");int min = Integer.parseInt(s1[0]);String[] s2 = s1[1].split("\\.");int sec = Integer.parseInt(s2[0]);int mill = 0;if (s2.length > 1)mill = Integer.parseInt(s2[1]);return min * 60 * 1000 + sec * 1000 + mill * 10;} catch (Exception e) {return -1;}}/** * 判断文件编码，防止文件解析成乱码 */public static String getCharset(File file) {String charset = "GBK";byte[] first3Bytes = new byte[3];try {boolean checked = false;BufferedInputStream bis = new BufferedInputStream(new FileInputStream(file));bis.mark(0);                       //一般读取前3个字节就可以判断文件的编码格式int read = bis.read(first3Bytes, 0, 3);if (read == -1)return charset;if (first3Bytes[0] == (byte) 0xFF && first3Bytes[1] == (byte) 0xFE) {charset = "UTF-16LE";checked = true;} else if (first3Bytes[0] == (byte) 0xFE&& first3Bytes[1] == (byte) 0xFF) {charset = "UTF-16BE";checked = true;} else if (first3Bytes[0] == (byte) 0xEF&& first3Bytes[1] == (byte) 0xBB&& first3Bytes[2] == (byte) 0xBF) {charset = "UTF-8";checked = true;}bis.reset();if (!checked) {int loc = 0;while ((read = bis.read()) != -1) {loc++;if (read >= 0xF0)break;if (0x80 <= read && read <= 0xBF)break;if (0xC0 <= read && read <= 0xDF) {read = bis.read();if (0x80 <= read && read <= 0xBF)continue;elsebreak;} else if (0xE0 <= read && read <= 0xEF) {read = bis.read();if (0x80 <= read && read <= 0xBF) {read = bis.read();if (0x80 <= read && read <= 0xBF) {charset = "UTF-8";break;} elsebreak;} elsebreak;}}}bis.close();} catch (Exception e) {e.printStackTrace();}return charset;}        //按照timePoint的大小进行升序排列private static class Sort implements Comparator<Lyrc> {public Sort() {}public int compare(Lyric tl1, Lyric tl2) {return sortUp(tl1, tl2);}private int sortUp(Lyric tl1, Lyric tl2) {if (tl1.timePoint < tl2.timePoint)return -1;else if (tl1.timePoint > tl2.timePoint)return 1;elsereturn 0;}}}

我们可以直接使用LrcUtils类, 导入到你的工程中，调用LrcUtils.readLRC(File);方法传入歌词文件就会返回解析的歌词数据. 

下面介绍LrcUtils类中的逻辑：

(1)首先从歌词文件中读取数据(按行读取, 在读取数据时调用方法getCharset获取文件的编码格式防止读取数据出现乱码), 每读取一行调用processLRC去将此行数据解析保存到Lyrc中.

(2)在processLRC中处理一行中多个时间戳的逻辑, 因为有的歌词文件为了方便把重复的歌词的时间放在一起。

(3)将获取的解析数据按照timePoint排序, 因为防止（2）中描述的情况，重复歌词的时间放在一起的问题，如果不排序的话，会导致歌词顺序乱套.

(4)计算每行歌词停留的时间

什么是为了防止重复歌词放在一行上？

歌词是这样的：

[02:17.62][00:27.46]为你我用了半年的积蓄[02:21.05][00:31.99]飘洋过海的来看你[02:24.81][00:35.60]为了这次相聚[02:27.59][00:38.16]我连见面时的呼吸都曾反复练习[02:33.48][00:43.79]言语从来没能将我的情谊表达千万分之一[02:40.91][00:51.47]为了这个遗憾[02:44.19][00:54.65]我在夜里想了又想不肯睡去[02:50.40][01:00.88]记忆它总是慢慢的积累[02:54.50][01:04.92]在我心中无法抹去[02:58.22][01:07.93]为了你的承诺[03:00.77][01:10.72]我在最绝望的时候都忍住不哭泣[03:08.46][01:17.06]陌生的城市啊！[03:12.81][01:22.20]熟悉的角落里[03:16.63][01:26.99]也曾彼此安慰[03:19.31][01:30.13]也曾相拥叹息[03:21.36][01:31.72]不管将会面对什么样的结局[03:58.95][03:25.36][01:35.83]在漫天风沙里 望着你远去[04:02.66][03:29.38][01:39.70]我竟悲伤的不能自己[04:06.82][03:34.02][01:43.83]多盼能送君千里[04:09.25][03:35.95][01:46.15]直到山穷水尽[04:11.46][03:38.51][01:58.96][01:48.44]一生和你相依

一句歌词前面多个时间tag.

2. 编写自定义TextView 去显示歌词

       (1)继承TextView， 处理onDraw方法

        (2)歌词绘制，区分当前行与普通行， 将当前行绘制在控件中心。指定两种Paint，来绘制两种不同文本。

        (3)每隔一个时间段(就是Lyrc中的sleepTime字段)更新显示内容，向上滚动

public class LricView extends TextView {private List<Lyric> lyricList;// 标记当前行private int currentLine = 0;private Paint currentPaint;private Paint otherPaint;private int currentColor = Color.GREEN;private int currentTextSize = 18;private int otherColor = Color.BLACK;private int otherTextSize = 15;// 行间距private int lineSpace = 25;//当前歌词字体private Typeface currentTypeface = Typeface.DEFAULT_BOLD;//其他歌词字体private Typeface otherTypeface = Typeface.SERIF;private Handler handler = new Handler() {@Overridepublic void handleMessage(Message msg) {invalidate(); // 刷新,会再次调用onDraw方法super.handleMessage(msg);}};public LricView(Context context, AttributeSet attrs) {super(context, attrs);currentPaint = new Paint();otherPaint = new Paint();lyricList = LrcUtils.readLRC(new File("/data/local/tmp/123456.lrc"));currentPaint.setColor(currentColor);currentPaint.setTextSize(currentTextSize);currentPaint.setTextAlign(Align.CENTER); // 画在中间currentPaint.setTypeface(currentTypeface);otherPaint.setColor(otherColor);otherPaint.setTextSize(otherTextSize);otherPaint.setTextAlign(Align.CENTER);otherPaint.setTypeface(otherTypeface);}@Overrideprotected void onDraw(Canvas canvas) {if (lyricList != null && currentLine < lyricList.size()) {Lyric lyrc = null;//绘制播放过的歌词for (int i = currentLine - 1; i >= 0; i--) {lyric = lyricList.get(i);canvas.drawText(lyrc.lricString, getWidth() / 2,getHeight() / 2 + lineSpace * (i - currentLine), otherPaint);}lyric = lyrcList.get(currentLine);// 绘制正在播放的歌词canvas.drawText(lyrc.lricString, getWidth() / 2,getHeight() / 2, currentPaint);                        //绘制未播放的歌词for (int i = currentLine + 1; i < lyrcList.size(); i++) {lyric = lyricList.get(i);canvas.drawText(lyrc.lricString, getWidth() / 2,getHeight() / 2 + lineSpace * (i - currentLine), otherPaint);}lyric = lyricList.get(currentLine);handler.sendEmptyMessageDelayed(10, lyrc.sleepTime);currentLine++;} else {canvas.drawText("未找到歌词", getWidth() / 2,getHeight() / 2, currentPaint);}super.onDraw(canvas);}}

在自定义LricView中调用LrcUtils.readLRC方法传入歌词文件获取歌词信息，然后通过handler去控制多长时间进行绘制.  LricView 可以直接使用.

3. 使用LricView

<RelativeLayout 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"    tools:context=".MainActivity" >    <com.example.lrcdemo.LricView        android:layout_width="match_parent"        android:layout_height="match_parent" /></RelativeLayout>

在布局文件中直接使用即可.

最终实现结果:

自此歌词处理完成, 贴出的代码都是可以直接使用参考, 关于快进快退音乐和倍速播放，歌词的处理逻辑就是修改lyric中的SleepTime, 不过逻辑也挺绕的.  这个歌词处理逻辑是我在做音乐播放器时参考学习别的教程, 在这里整理出来给大家参考, 如果有任何问题可以留言.