android自定义控件－－渐变进度条

　效果图如下：　

　实现代码：

import android.content.Context;

import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.LinearGradient;
import android.graphics.Paint;
import android.graphics.RectF;
import android.graphics.Shader;
import android.util.AttributeSet;
import android.view.View;

/**
 * Created by dawn on 2017/12/7.
 *
 * 自定义渐变进度条
 */

public class ProgressView extends View{

    public ProgressView(Context context) {
        super(context);
    }

    /**渐变颜色*/
    private static final int[] SECTION_COLORS = {0xff123b9d,0xff4e9bce,0xff85f4fb};
    /**进度条最大值*/
    private float maxCount;
    /**进度条当前值*/
    private float currentCount;
    /**画笔*/
    private Paint mPaint;
    private int mWidth,mHeight;//设置宽度和高度
    public ProgressView(Context context, AttributeSet attrs,
                              int defStyleAttr) {
        super(context, attrs, defStyleAttr);
    }
    public ProgressView(Context context, AttributeSet attrs) {
        super(context, attrs);
    }

    @Override
    protected void onDraw(Canvas canvas) {
        super.onDraw(canvas);

        mPaint = new Paint();
        mPaint.setAntiAlias(true);
        int round = mHeight/2;
        //蓝色边框
        //绘制阴影效果
        int beginP=dipToPx(0);
        mPaint = new Paint(Paint.ANTI_ALIAS_FLAG);
        mPaint.setColor(0xff00a3d5);
        mPaint.setStyle(Paint.Style.FILL);
        mPaint.setShadowLayer(100, 0, 0,Color.WHITE);
        RectF rectBg = new RectF(beginP, beginP, mWidth, mHeight);
        canvas.drawRoundRect(rectBg, round, round, mPaint);
        //深蓝色边框
        mPaint.setColor(Color.rgb(7, 38, 85));
        RectF rectBg1 = new RectF(beginP+2, beginP+2, mWidth-2, mHeight-2);
        canvas.drawRoundRect(rectBg1, round, round, mPaint);
        mPaint.setColor(0xff072655);
        RectF rectBlackBg = new RectF(beginP+4, beginP+4, mWidth-4, mHeight-4);
        canvas.drawRoundRect(rectBlackBg, round, round, mPaint);

        float section = currentCount/maxCount;
        RectF rectProgressBg = new RectF(beginP+3, beginP+3, (mWidth-3)*section, mHeight-3);
        if(section <= 1.0f/3.0f){
            if(section != 0.0f){
                mPaint.setColor(SECTION_COLORS[0]);
            }else{
                mPaint.setColor(Color.TRANSPARENT);
            }
        }else{
            int count = (section <= 1.0f/3.0f*2 ) ? 2 : 3;
            int[] colors = new int[count];
            System.arraycopy(SECTION_COLORS, 0, colors, 0, count);
            float[] positions = new float[count];
            if(count == 2){
                positions[0] = 0.0f;
                positions[1] = 1.0f-positions[0];
            }else{
                positions[0] = 0.0f;
                positions[1] = (maxCount/3)/currentCount;
                positions[2] = 1.0f-positions[0]*2;
            }
            positions[positions.length-1] = 1.0f;
            //线性渲染
            LinearGradient shader = new LinearGradient(3, 3, (mWidth-3)*section, mHeight-3, colors,null, Shader.TileMode.MIRROR);
            mPaint.setShader(shader);
        }
        canvas.drawRoundRect(rectProgressBg, round, round, mPaint);
    }

    /**
     * dp转换成像素
     * @param dip
     * @return
     */
    private int dipToPx(int dip) {
        float scale = getContext().getResources().getDisplayMetrics().density;
        return (int) (dip * scale + 0.5f * (dip >= 0 ? 1 : -1));
    }

    /***
     * 设置最大的进度值
     * @param maxCount
     */
    public void setMaxCount(float maxCount) {
        this.maxCount = maxCount;
    }

    /***
     * 设置当前的进度值
     * @param currentCount
     */
    public void setCurrentCount(float currentCount) {
        this.currentCount = currentCount > maxCount ? maxCount : currentCount;
        invalidate();
    }

    /**
     * UNSPECIFIED 父容器没有对当前View有任何限制，当前View可以任意取尺寸
     * EXACTLY 当前的尺寸就是当前View应该取的尺寸
     * AT_MOST 当前尺寸是当前View能取的最大尺寸
     * @param widthMeasureSpec
     * @param heightMeasureSpec
     */
    @Override
    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
        int widthSpecMode = MeasureSpec.getMode(widthMeasureSpec);
        int widthSpecSize = MeasureSpec.getSize(widthMeasureSpec);
        int heightSpecMode = MeasureSpec.getMode(heightMeasureSpec);
        int heightSpecSize = MeasureSpec.getSize(heightMeasureSpec);
        if (widthSpecMode == MeasureSpec.EXACTLY || widthSpecMode == MeasureSpec.AT_MOST) {
            mWidth = widthSpecSize;
        } else {
            mWidth = 0;
        }
        if (heightSpecMode == MeasureSpec.AT_MOST || heightSpecMode == MeasureSpec.UNSPECIFIED) {
            mHeight = dipToPx(25);
        } else {
            mHeight = heightSpecSize;
        }
        setMeasuredDimension(mWidth, mHeight);
    }

}

问题：

　　效果图还有一层阴影，我怎么改都实现不了。若有人知道，劳烦告诉我一声，谢谢。