自定义进度条

一、先上效果图

效果图

二、思路

 1、绘制底色（灰色）
 2、绘制进度（蓝色）
 3、绘制最大的进度（纯蓝色）

三、实现

1）绘制底色

 RectF rf = new RectF(0, 0, mWidth, mHeight);
 /*绘制圆角矩形，背景色为画笔颜色*/
 mPaint.setColor(Color.rgb(220, 220, 220));
 canvas.drawRoundRect(rf, round, round, mPaint);
 /*设置progress内部是灰色*/
 mPaint.setColor(Color.rgb(242, 241, 246));
 RectF rectBlackBg = new RectF(3, 3, mWidth - 3, mHeight - 3);
 canvas.drawRoundRect(rectBlackBg, round, round, mPaint);

2）绘制进度

isMax 判断是否为最大的进度

  //设置进度条进度及颜色
    float section = currentCount / maxCount;
    RectF rectProgressBg = new RectF(0, 0, mWidth * section, mHeight);
    if (section != 0.0f) {
        if (isMax){
            mPaint.setColor(Color.rgb(75, 199, 247));
            canvas.drawRoundRect(rectProgressBg, round, round, mPaint);
        }else {
            RectF s1 = new RectF(0, 0, mWidth * section, mHeight);
            mPaint.setColor(Color.rgb(83, 202, 247));
            canvas.drawRoundRect(s1, round, round, mPaint);
            RectF s2 = new RectF(3, 3, mWidth * section-3, mHeight-3);
            mPaint.setColor(Color.rgb(210, 232, 245));
            canvas.drawRoundRect(s2, round, round, mPaint);
        }
    } else {
        mPaint.setColor(Color.TRANSPARENT);
        canvas.drawRoundRect(rectProgressBg, round, round, mPaint);
    }

3）ProgressView完整代码

public class ProgressView extends View {
    /**
     * 进度条最大值
     */
    private float maxCount;
    /**
     * 进度条当前值
     */
    private float currentCount;
    /**
     * 画笔
     */
    private Paint mPaint;
    /**
     * 设置为最大项
     **/
    private boolean isMax;

    private int mWidth, mHeight;

    public ProgressView(Context context, AttributeSet attrs, int defStyle) {
        super(context, attrs, defStyle);
        // TODO Auto-generated constructor stub
    }

    public ProgressView(Context context, AttributeSet attrs) {
        super(context, attrs);
        // TODO Auto-generated constructor stub
    }

    public ProgressView(Context context) {
        super(context);
        // TODO Auto-generated constructor stub
    }

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

    /***
     * 设置为最大项
     */
    public void setIsMax(boolean b) {
        this.isMax = b;
    }
    

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

    @Override
    protected void onDraw(Canvas canvas) {
        // TODO Auto-generated method stub
        super.onDraw(canvas);

        mPaint = new Paint();
        //设置抗锯齿效果
        mPaint.setAntiAlias(true);
        //设置画笔颜色
        mPaint.setColor(Color.BLACK);
        int round = mHeight / 2;

        RectF rf = new RectF(0, 0, mWidth, mHeight);
        /*绘制圆角矩形，背景色为画笔颜色*/
        mPaint.setColor(Color.rgb(220, 220, 220));
        canvas.drawRoundRect(rf, round, round, mPaint);
        /*设置progress内部是灰色*/
        mPaint.setColor(Color.rgb(242, 241, 246));
        RectF rectBlackBg = new RectF(3, 3, mWidth - 3, mHeight - 3);
        canvas.drawRoundRect(rectBlackBg, round, round, mPaint);
        //设置进度条进度及颜色
        float section = currentCount / maxCount;
        RectF rectProgressBg = new RectF(0, 0, mWidth * section, mHeight);


        if (section != 0.0f) {
            if (isMax){
                mPaint.setColor(Color.rgb(75, 199, 247));
                canvas.drawRoundRect(rectProgressBg, round, round, mPaint);
            }else {
                RectF s1 = new RectF(0, 0, mWidth * section, mHeight);
                mPaint.setColor(Color.rgb(83, 202, 247));
                canvas.drawRoundRect(s1, round, round, mPaint);
                RectF s2 = new RectF(3, 3, mWidth * section-3, mHeight-3);
                mPaint.setColor(Color.rgb(210, 232, 245));
                canvas.drawRoundRect(s2, round, round, mPaint);
            }
        } else {
            mPaint.setColor(Color.TRANSPARENT);
            canvas.drawRoundRect(rectProgressBg, round, round, mPaint);
        }

    }
    
    private int dipToPx(int dip) {
        float scale = getContext().getResources().getDisplayMetrics().density;
        return (int) (dip * scale + 0.5f * (dip >= 0 ? 1 : -1));
    }

    @Override
    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
        // TODO Auto-generated method stub
        super.onMeasure(widthMeasureSpec, heightMeasureSpec);
        int widthSpecMode = MeasureSpec.getMode(widthMeasureSpec);
        int heightSpecMode = MeasureSpec.getMode(heightMeasureSpec);
        int widthSpecSize = MeasureSpec.getSize(widthMeasureSpec);
        int heightSpecSize = MeasureSpec.getSize(heightMeasureSpec);
        //MeasureSpec.EXACTLY，精确尺寸
        if (widthSpecMode == MeasureSpec.EXACTLY || widthSpecMode == MeasureSpec.AT_MOST) {
            mWidth = widthSpecSize;
        } else {
            mWidth = 0;
        }
        //MeasureSpec.AT_MOST，最大尺寸，只要不超过父控件允许的最大尺寸即可，MeasureSpec.UNSPECIFIED未指定尺寸
        if (heightSpecMode == MeasureSpec.AT_MOST || heightSpecMode == MeasureSpec.UNSPECIFIED) {
            mHeight = dipToPx(20);
        } else {
            mHeight = heightSpecSize;
        }
        //设置控件实际大小
        setMeasuredDimension(mWidth, mHeight);


    }

}

如有意见和建议，及时沟通。