同事写的圆角Layout处理，因为CardView处理有闪白屏和圆角毛边现象

        <declare-styleable name="RoundFrameLayout">
            <attr name="Round" format="dimension" />
        </declare-styleable>

    public class RoundFrameLayout extends FrameLayout {
    private final Path mPath;
    private final Paint mPaint;
    private final RectF mRectF;
    private final boolean isClipBackground;
    private float mRadius;

    @Keep
    public RoundFrameLayout(@NonNull Context context, @Nullable AttributeSet attrs) {
        super(context, attrs, 0);

        isClipBackground = true;

        mPath = new Path();
        mPaint = new Paint(Paint.ANTI_ALIAS_FLAG);
        mRectF = new RectF();

        mPaint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.DST_IN));

        TypedArray array = context.obtainStyledAttributes(attrs,
                R.styleable.RoundFrameLayout, 0, 0);
        mRadius = array.getDimension(R.styleable.RoundFrameLayout_Round, 50f);
        array.recycle();
    }

    public void setRadius(float radius) {
        mRadius = radius;
        postInvalidate();
    }

    @Keep
    @Override
    protected void onSizeChanged(int w, int h, int oldw, int oldh) {
        super.onSizeChanged(w, h, oldw, oldh);
        mRectF.set(0, 0, w, h);
    }

    @Keep
    @Override
    public void draw(Canvas canvas) {
        super.draw(canvas);
        if (Build.VERSION.SDK_INT >= P) {
            draw28(canvas);
        } else {
            draw27(canvas);
        }
    }

    @Keep
    @Override
    protected void dispatchDraw(Canvas canvas) {
        if (Build.VERSION.SDK_INT >= P) {
            dispatchDraw28(canvas);
        } else {
            dispatchDraw27(canvas);
        }
    }

    private void draw27(Canvas canvas) {
        if (isClipBackground) {
            canvas.saveLayer(mRectF, null, Canvas.ALL_SAVE_FLAG);
            super.draw(canvas);
            canvas.drawPath(genPath(), mPaint);
            canvas.restore();
        } else {
            super.draw(canvas);
        }
    }

    private void draw28(Canvas canvas) {
        if (isClipBackground) {
            canvas.save();
            canvas.clipPath(genPath());
            super.draw(canvas);
            canvas.restore();
        } else {
            super.draw(canvas);
        }
    }

    private void dispatchDraw27(Canvas canvas) {
        canvas.saveLayer(mRectF, null, Canvas.ALL_SAVE_FLAG);
        super.dispatchDraw(canvas);
        canvas.drawPath(genPath(), mPaint);
        canvas.restore();
    }

    private void dispatchDraw28(Canvas canvas) {
        canvas.save();
        canvas.clipPath(genPath());
        super.dispatchDraw(canvas);
        canvas.restore();
    }

    private Path genPath() {
        mPath.reset();
        mPath.addRoundRect(mRectF, mRadius, mRadius, Path.Direction.CW);
        return mPath;
    }

}