Android 手机影音 开发过程记录（六）

前一篇已经将音乐播放及切换的相关逻辑弄好了，今天主要理一下剩余的部分，包含：

1. 自己定义通知栏的布局及逻辑处理

2. 滚动歌词的绘制

3. 歌词解析

效果图

通知栏

自己定义布局：

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal"
android:id="@+id/layout_notification"
android:padding="10dp" >

<ImageView
android:layout_width="40dp"
android:layout_height="40dp"
android:background="@mipmap/ic_launcher" />

<LinearLayout
android:layout_width="0dp"
android:layout_height="40dp"
android:layout_weight="1"
android:layout_marginLeft="10dp"
android:orientation="vertical" >

<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:singleLine="true"
android:text="标题"
android:id="@+id/tv_notification_title"
android:textColor="@color/white"
android:textSize="17sp" />

<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:singleLine="true"
android:text="艺术家"
android:id="@+id/tv_notification_content"
android:textColor="@color/gray_white"
android:textSize="14sp" />
</LinearLayout>

<LinearLayout android:layout_width="0dp"
android:layout_weight="1"
android:gravity="center"
android:orientation="horizontal"
android:layout_height="40dp">

<ImageView android:layout_width="30dp"
android:layout_height="30dp"
android:layout_marginRight="20dp"
android:id="@+id/btn_notification_pre"
android:background="@mipmap/icon_notification_pre"/>

<ImageView android:layout_width="30dp"
android:layout_height="30dp"
android:id="@+id/btn_notification_next"
android:background="@mipmap/icon_notification_next"/>

</LinearLayout>

</LinearLayout>

通知栏的相关逻辑：

下一首

上一首

进入播放页

/**
* 发送自己定义布局的通知
*/
private void sendNotification() {
Notification.Builder builder = new Notification.Builder(AudioPlayerService.this);
builder.setOngoing(true)
.setSmallIcon(R.mipmap.notification_music_playing)
.setTicker("正在播放:" + StringUtil.formatAudioName(audioList.get(currentPosition).getTitle()))
.setWhen(System.currentTimeMillis())
.setContent(getRemoteViews());

startForeground(1, builder.build());
}

private RemoteViews getRemoteViews() {
RemoteViews remoteViews = new RemoteViews(getPackageName(),
R.layout.layout_music_notification);
remoteViews.setTextViewText(R.id.tv_notification_title, StringUtil.formatAudioName(audioList.get(currentPosition).getTitle()));
remoteViews.setTextViewText(R.id.tv_notification_content, audioList.get(currentPosition).getArtist());

remoteViews.setOnClickPendingIntent(R.id.btn_notification_pre, getPrePendingIntent());
remoteViews.setOnClickPendingIntent(R.id.btn_notification_next, getNextPendingIntent());
remoteViews.setOnClickPendingIntent(R.id.layout_notification, getContentPendingIntent());

return remoteViews;
}

private PendingIntent getPrePendingIntent() {
Intent intent = new Intent(AudioPlayerService.this, AudioPlayerService.class);
intent.putExtra("viewAction", ACTION_NOTIFICATION_PRE);
intent.putExtra("isFromNotification", true);
PendingIntent pendingIntent = PendingIntent.getService(AudioPlayerService.this, 1, intent, PendingIntent.FLAG_UPDATE_CURRENT);
return pendingIntent;
}

private PendingIntent getNextPendingIntent() {
Intent intent = new Intent(AudioPlayerService.this, AudioPlayerService.class);
intent.putExtra("viewAction", ACTION_NOTIFICATION_NEXT);
intent.putExtra("isFromNotification", true);
PendingIntent pendingIntent = PendingIntent.getService(AudioPlayerService.this, 2, intent, PendingIntent.FLAG_UPDATE_CURRENT);
return pendingIntent;
}

private PendingIntent getContentPendingIntent() {
Intent intent = new Intent(AudioPlayerService.this, AudioPlayerActivity.class);
Bundle bundle = new Bundle();
bundle.putInt("viewAction", ACTION_NOTIFICATION_LAYOUT);
bundle.putBoolean("isFromNotification", true);
intent.putExtras(bundle);
PendingIntent pendingIntent = PendingIntent.getActivity(AudioPlayerService.this, 3, intent, PendingIntent.FLAG_UPDATE_CURRENT);
return pendingIntent;
}

/*发送通知的方法应该在音乐准备完毕和開始播放的时候调用*/

private OnPreparedListener onPreparedListener = new OnPreparedListener() {
@Override
public void onPrepared(MediaPlayer mp) {
mediaPlayer.start();
notifyPrepared();
sendNotification();
}
};
public void start() {
if (mediaPlayer != null) {
mediaPlayer.start();
}
sendNotification();
}

//音乐准备暂停时移除通知
public void pause() {
if (mediaPlayer != null) {
mediaPlayer.pause();
}
stopForeground(true);//移除通知
}

歌词绘制

思路：自己定义LyricView继承TextView。覆盖onSizeChanged(),onDraw()方法。

绘制一行居中文本

/**
* 绘制水平居中的歌词文本
*
* @param canvas  画布
* @param text    文本
* @param y       竖直方向的y坐标
* @param isLight 是否高亮
*/
private void drawCenterHorizontalText(Canvas canvas, String text, float y, boolean isLight) {
paint.setColor(isLight ?

LYRCI_HIGHLIGHT_COLOR : LYRIC_DEFAULT_COLOR);
paint.setTextSize(isLight ?
getResources().getDimension(R.dimen.lyric_highlight_textsize)
: getResources().getDimension(R.dimen.lyric_default_textsize));
float x = width / 2 - paint.measureText(text) / 2;
canvas.drawText(text, x, y, paint);
}

绘制多行歌词

/**
* 绘制全部的歌词
*
* @param canvas 画布
*/
private void drawLyricList(Canvas canvas) {
Lyric lightLyric = lyricList.get(lightLyricIndex);

//1.首先将高亮行的歌词绘制出来，作为一个參照物
float lightLyricY = height / 2 + getTextHeight(lightLyric.getContent()) / 2;
drawCenterHorizontalText(canvas, lightLyric.getContent(), lightLyricY, true);
//2.遍历高亮行之前的歌词，并绘制出来
for (int pre = 0; pre < lightLyricIndex; pre++) {
Lyric lyric = lyricList.get(pre);
float y = lightLyricY - (lightLyricIndex - pre) * LYRIC_ROW_HEIGHT;
drawCenterHorizontalText(canvas, lyric.getContent(), y, false);
}
//3.遍历高亮行之后的歌词，并绘制出来
for (int next = lightLyricIndex + 1; next < lyricList.size(); next++) {
Lyric lyric = lyricList.get(next);
float y = lightLyricY + (next - lightLyricIndex) * LYRIC_ROW_HEIGHT;
drawCenterHorizontalText(canvas, lyric.getContent(), y, false);
}

}

/**
* 获取文本的高度
*
* @param text 文本
* @return 文本的高度
*/
private float getTextHeight(String text) {
Rect bounds = new Rect();
paint.getTextBounds(text, 0, text.length(), bounds);
return bounds.height();
}

滚动歌词

/**
* 滚动歌词
*/
public void roll(long currentPosition,long audioDuration){
this.currentPosition = currentPosition;
this.audioDuration = audioDuration;
//1. 依据歌词播放的position。计算出高亮行的索引lightLyricIndex
if(lyricList.size() != 0){
//1.依据当前歌曲播放的位置去计算lightLyricIndex
caculateLightLyricIndex();
}

//2. 拿到新的lightLyricIndex之后，更新view
invalidate();
}

/**
* 计算高亮歌词的索引值
* 仅仅要当前音乐的position大于当前行的startPoint。
* 而且小于下一行的startPoint，就是高亮行
*/
private void caculateLightLyricIndex() {
for (int i = 0; i < lyricList.size(); i++) {
long startPoint = lyricList.get(i).getStartPoint();
if(i == lyricList.size() - 1){//最后一行
if(currentPosition > startPoint){
lightLyricIndex = i;
}
}else{//不是最后一行
Lyric next = lyricList.get(i + 1);
if(currentPosition > startPoint && currentPosition < next.getStartPoint()){
lightLyricIndex = i;
}
}

}
}

平滑滚动歌词

/**
* 绘制全部的歌词
*
* @param canvas 画布
*/
private void drawLyricList(Canvas canvas) {
Lyric lightLyric = lyricList.get(lightLyricIndex);
//平滑移动歌词
//1. 算出歌词的总的播放时间 即 下一行的startPoint - 当前的startPoint
int totalDuration;
if(lightLyricIndex==(lyricList.size()-1)){
//假设最后一行是高亮行，则拿歌曲总时间减去当前的startPoint
totalDuration = (int) (audioDuration - lightLyric.getStartPoint());
}else {
totalDuration = (int) (lyricList.get(lightLyricIndex+1).getStartPoint()-lightLyric.getStartPoint());
}
//2. 算出当前已经播放的秒数占总时间的百分比 currentAudioPosition - startPoint
float offsetPosition = (int) (currentPosition - lightLyric.getStartPoint());
float percent = offsetPosition/totalDuration;
//3. 依据百分比算出应该移动的距离 percent * LYRIC_ROW_HEIGHT
float dy = LYRIC_ROW_HEIGHT * percent;
canvas.translate(0, -dy);

//1.首先将高亮行的歌词绘制出来，作为一个參照物
float lightLyricY = height / 2 + getTextHeight(lightLyric.getContent()) / 2;
drawCenterHorizontalText(canvas, lightLyric.getContent(), lightLyricY, true);
//2.遍历高亮行之前的歌词。并绘制出来
for (int pre = 0; pre < lightLyricIndex; pre++) {
Lyric lyric = lyricList.get(pre);
float y = lightLyricY - (lightLyricIndex - pre) * LYRIC_ROW_HEIGHT;
drawCenterHorizontalText(canvas, lyric.getContent(), y, false);
}
//3.遍历高亮行之后的歌词，并绘制出来
for (int next = lightLyricIndex + 1; next < lyricList.size(); next++) {
Lyric lyric = lyricList.get(next);
float y = lightLyricY + (next - lightLyricIndex) * LYRIC_ROW_HEIGHT;
drawCenterHorizontalText(canvas, lyric.getContent(), y, false);
}

}

提供设置歌词的方法

public void setLyricList(ArrayList<Lyric> lyricList){
this.lyricList = lyricList;
if(this.lyricList==null){
hasNoLyric = true;
}
}

歌词解析

读取每一行歌词文本

解析每一行歌词

对歌词集合进行排序

/**
* 歌词解析的工具类
*/
public class LyricParser {
public static ArrayList<Lyric> parseLyricFromFile(File lyricFile){
if(lyricFile==null || !lyricFile.exists())return null;
ArrayList<Lyric> list = new ArrayList<Lyric>();

try {
//1.读取每一行歌词文本
BufferedReader reader = new BufferedReader(new InputStreamReader
(new FileInputStream(lyricFile),"utf-8"));
String line;
while((line=reader.readLine())!=null){
//2.解析每一行歌词
//[00:04.05][00:24.05][01:24.05]北京北京   -> split("\\]")
//[00:04.05   [00:24.05   [01:24.05       北京北京
String[] arr = line.split("\\]");
for (int i = 0; i < arr.length-1; i++) {
Lyric lyric = new Lyric();
lyric.setContent(arr[arr.length-1]);//设置歌词内容
lyric.setStartPoint(formatStartPoint(arr[i]));

list.add(lyric);
}
}
//3.对歌词集合进行排序
Collections.sort(list);//从小到大
} catch (Exception e) {
e.printStackTrace();
}

return list;
}

/**
* 将[00:04.05转long类型的时间
* @param str
* @return
*/
private static long formatStartPoint(String str){
str = str.substring(1);//00:04.05
//1.先以冒号切割
String[] arr1 = str.split("~i");//00    04.05
String[] arr2 = arr1[1].split("\\.");//04    05
int minute = Integer.parseInt(arr1[0]);//得到多少分钟
int second = Integer.parseInt(arr2[0]);//得到多少秒
int mills = Integer.parseInt(arr2[1]);//得到多少10毫秒
return mills*10 + second*1000 + minute*60*1000;
}

}

/**模拟歌词载入模块
* TODO：拿歌曲id去server请求相应的歌词文件
*/
public class LyricLoader {
//    private static final String LYRIC_DIR = Environment.getExternalStorageDirectory()+"/MIUI/music/lyric";
private static final String LYRIC_DIR = Environment.getExternalStorageDirectory()+"/test/audio";
public static File loadLyricFileByName(String audioName){
File file = new File(LYRIC_DIR,StringUtil.formatAudioName(audioName)+".lrc");
LogUtils.i(LYRIC_DIR);
if(!file.exists()){
file = new File(LYRIC_DIR,StringUtil.formatAudioName(audioName)+".txt");
}
return file;
}
}

好了。手机影音项目的整理就到这里。