圆角矩形的比例条

public class RatioBar extends View {
    private float mMaxRatio = 0.8f;
    private float mMinRatio = 0.2f;
    private final RectF mRectF = new RectF();
    private final Paint mPaint = new Paint(Paint.ANTI_ALIAS_FLAG);
    private int mSplitWidth = 10;
    private int mRiseColor, mFallColor;

    private int mRise, mFall;


    public RatioBar(@NonNull Context context) {
        this(context, null);
    }

    public RatioBar(@NonNull Context context, @Nullable AttributeSet attrs) {
        this(context, attrs, 0);
    }

    public RatioBar(@NonNull Context context, @Nullable AttributeSet attrs, int defStyleAttr) {
        super(context, attrs, defStyleAttr);
        init(context, attrs);
    }

    private void init(Context context, AttributeSet attrs) {
        mRiseColor = getColor(xxx);
        mFallColor = getColor(xxx);
    }

    @SuppressLint("EMDrawAllocation")
    @Override
    protected void onDraw(Canvas canvas) {
        RectF rectF = mRectF;
        Paint paint = mPaint;

        int paddingLeft = getPaddingLeft();
        int paddingTop = getPaddingTop();
        int paddingRight = getPaddingRight();
        int paddingBottom = getPaddingBottom();

        int startX = paddingLeft;
        int startY = paddingTop;

        int width = getWidth() - paddingLeft - paddingRight;
        int height = getHeight() - paddingTop - paddingBottom;
        // 约定最小宽高比3:1
        if (width < height * 3) {
            startY = (height - width / 3) / 2 + paddingTop;
            height = width / 3;
        }
        int radius = height / 2;
        int ratioStart = radius;
        int ratioEnd = width - radius;
        int splitWidth = mSplitWidth;
        int ratioWidth;

        int rise = mRise;
        int fall = mFall;
        int total = rise + fall;
        if (rise == 0 || fall == 0) {
            
            Path path = new Path();
            path.moveTo(startX + ratioStart, startY);
            path.lineTo(startX + ratioEnd, startY);
            rectF.set(startX + ratioEnd - radius, startY, startX + ratioEnd + radius, startY + height);
            path.arcTo(rectF, -90, 180, false);
            path.lineTo(startX + ratioStart, startY + height);
            rectF.set(startX, startY, startX + height, startY + height);
            path.arcTo(rectF, 90, 180, false);
            path.close();
            paint.setStyle(Paint.Style.FILL);
            if (fall == 0) {
                paint.setColor(mRiseColor);
            } else {
                paint.setColor(mFallColor);
            }
            canvas.drawPath(path, paint);
        } else {
           
            int triangleWidth = radius;// 中间斜着的三角的宽度
            ratioWidth = ratioEnd - ratioStart - splitWidth - triangleWidth;//比例条的宽度

            float fixRiseRatio = Math.max(mMinRatio, Math.min(mMaxRatio, rise / (float) total));
            int riseWidth = (int) (ratioWidth * fixRiseRatio);
            int fallWidth = ratioWidth - riseWidth;

            Path path = new Path();
            path.moveTo(startX + ratioStart, startY);
            path.lineTo(startX + ratioStart + riseWidth + triangleWidth, startY);
            path.lineTo(startX + ratioStart + riseWidth, startY + height);
            path.lineTo(startX + ratioStart, startY + height);
            rectF.set(startX, startY, startX + height, startY + height);
            path.arcTo(rectF, 90, 180, false);
            path.close();
            paint.setStyle(Paint.Style.FILL);
            paint.setColor(mRiseColor);
            canvas.drawPath(path, paint);

            path = new Path();
            path.moveTo(startX + ratioEnd, startY + height);
            path.lineTo(startX + ratioEnd - fallWidth - triangleWidth, startY + height);
            path.lineTo(startX + ratioEnd - fallWidth, startY);
            path.lineTo(startX + ratioEnd, startY);
            rectF.set(startX + ratioEnd - radius, startY, startX + ratioEnd + radius, startY + height);
            path.arcTo(rectF, -90, 180, false);
            path.close();
            paint.setStyle(Paint.Style.FILL);
            paint.setColor(mFallColor);
            canvas.drawPath(path, paint);
        }
    }
    public void setSplitWidth(int splitWidth) {
        mSplitWidth = splitWidth;
    }

    /**
     * 给展示的比例设置一个最大最小的限制
     * @param maxRatio
     * @param minRatio
     */
    public void setRatioLimit(float minRatio, float maxRatio) {
        if (maxRatio <= minRatio) {
            return;
        }
        mMaxRatio = Math.max(0, Math.min(maxRatio, 1));
        mMinRatio = Math.max(0, Math.min(minRatio, 1));
    }
    public void setData(int rise, int fall) {
        this.mRise = rise;
        this.mFall = fall;

        postInvalidate();
    }
}