Android歌词显示控件TextView自定义

 Java代码：MyLyricView1 

package com.itheima.videoplay.words;
import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.support.annotation.Nullable;
import android.util.AttributeSet;
import android.widget.TextView;
import java.util.ArrayList;

public class MyLyricView1 extends TextView {
    // 歌词类
    private ArrayList lyrics;
    private Paint paint;
    private Paint whitepaint;
    private int width;
    private int height;
//歌词列表中的索引，是第几句歌词
    private int index=6;
//  每行的高
    private float textHeight ;
// 当前歌词内容
    private String content;
// 时间戳
    private long timePoint;
// 休眠时间或者高亮显示的时间
    private long sleepTime;
    // 当前播放位置
    private float currentPositon;
    public ArrayList getLyrics() {
        return lyrics;
    }
    public void setLyrics(ArrayList lyrics) {
        this.lyrics = lyrics;
    }
    public MyLyricView1(Context context) {
        this(context,null);
    }
    public MyLyricView1(Context context, @Nullable AttributeSet attrs) {
        this(context, attrs,0);
    }
    public MyLyricView1(Context context, @Nullable AttributeSet attrs, int defStyleAttr) {
        super(context, attrs, defStyleAttr);
        initView(context);
    }
    @Override
    protected void onSizeChanged(int w, int h, int oldw, int oldh) {
        super.onSizeChanged(w, h, oldw, oldh);
        width = w;
        height = h;
    }
    public void setshowNextLyric(int currentPosition) {
//        this.currentPositon= currentPosition;
//        if(lyrics == null ||  lyrics.size() == 0 ){
//            return;
//        }
//        for (int i = 1; i < lyrics.size(); i++) {
//
//            if(currentPosition = lyrics.get(tempIndex).getTimePoint()){
//                    //当前正在播放的哪句歌词
//                    index = tempIndex;
//                    sleepTime = lyrics.get(index).getSleepTime();
//                    timePoint = lyrics.get(index).getTimePoint();
//                }
//
//            }
//        }
        currentPosition++;
        this.index=currentPosition;
        //重新绘制
        invalidate();//在主线程中
        //子线程
//        postInvalidate();
    }
    private void initView(Context context) {
        textHeight = DensityUtil.dip2px(context,18);//对应的像数
        //创建画笔 画中间内容
        paint = new Paint();
        paint.setColor(Color.GREEN);
        paint.setTextSize(DensityUtil.dip2px(context,16));
        paint.setAntiAlias(true);
        //设置居中对齐，画出来的内容会在View中居中
        paint.setTextAlign(Paint.Align.CENTER);
        // 画上下内容
        whitepaint = new Paint();
        whitepaint.setColor(Color.WHITE);
        whitepaint.setTextSize(DensityUtil.dip2px(context,16));
        whitepaint.setAntiAlias(true);
        //设置居中对齐
        whitepaint.setTextAlign(Paint.Align.CENTER);
  // 测试代码，假的歌词
        lyrics = new ArrayList();
        Lyric lyric = new Lyric();
        for (int i = 0; i 0 ){
            //1. 绘制歌词:绘制当前句
            String currentText = lyrics.get(index).getContent();
            canvas.drawText(currentText, width / 2, height / 2, paint);
            // 2. 绘制前面部分
            float tempY = height / 2;//Y轴的中间坐标
            for (int i = index - 1; i >= 0; i--) {
                //每一句歌词
                String preContent = lyrics.get(i).getContent();
                tempY = tempY - textHeight;
                if (tempY < 0) {
                    break;
                }
                
                canvas.drawText(preContent, width / 2, tempY, whitepaint);
            }
            // 3. 绘制后面部分
            tempY = height / 2;//Y轴的中间坐标
            for (int i = index + 1; i  height) {
                    break;
                }
                canvas.drawText(nextContent, width / 2, tempY, whitepaint);
            }
        }else{
            //没有歌词
            canvas.drawText("没有歌词", width / 2, height / 2, paint);
        }
    }
}

public class LyricActivity extends Activity {
    MyLyricView1 myLyricView1;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_lyric);
        myLyricView1 = findViewById(R.id.mylyriceview1);
    }
    int index=6;
    public void nextSentence(View veiw){
        myLyricView1.setshowNextLyric(index++);
    }
}