bigstark

// reset paint object and set color, style, alpha by step
private void resetPaint(int step) {
    paint.reset();

    paint.setAntiAlias(true);
    paint.setStyle(Paint.Style.FILL);
    paint.setColor(color);

    if (step < 3) {
        paint.setAlpha((int) (255 - (step + frame) * (255 - ALPHA_FINAL) / 3));

bigstark

// "positive" is increasing positively horizontally
private float[] getHorizontalCenter(int width, int height, boolean positive) {
    float x = (width - 2 * radius) * (positive ? frame : 1 - frame) + radius;
    float y = positive ? radius : height - radius;
    return new float[] {x, y};
}

// "negative" is increasing negatively vertically
private float[] getVerticalCenter(int width, int height, boolean negative) {
    float x = negative ? width - radius : radius;

bigstark

@Override
protected void onDraw(Canvas canvas) {
    super.onDraw(canvas);
    int width = getWidth();
    int height = getHeight();

    // o ㅡㅡ o
    //
    //
    // o     o

bigstark

public void start() {
    ValueAnimator animator = ValueAnimator.ofInt(0, 1);
    animator.addUpdateListener(new ValueAnimator.AnimatorUpdateListener() {
        @Override
        public void onAnimationUpdate(ValueAnimator animation) {
            frame = animation.getAnimatedFraction();
            postInvalidate();
        }
    });
    animator.setDuration(durationRotate);

bigstark

public void setRadius(int radius) {
    this.radius = radius;
    postInvalidate();
}


public void setColor(int color) {
    this.color = color;
    postInvalidate();
}

bigstark

@Override
protected void onDraw(Canvas canvas) {
    super.onDraw(canvas);
    int width = getWidth();
    int height = getHeight();

    float size = (width > height ? height : width) - tileMargin * 2;
    float tileSize = size / 3;

bigstark

// 참고로 안돌려보고 여기에서 대충 만든거라 컴파일 에러날 확률이 매우 높습니다.
override fun getItemOffsets(outRect: Rect, view: View, parent: RecyclerView, state: RecyclerView.State) {
    super.getItemOffsets(outRect, view, parent, state)
    outRect.setEmpty()

    val position = parent.getChildAdapterPosition(view).takeIf { it != RecyclerView.NO_POSITION } ?: run {
        return
    }

    val space = 20.dp

bigstark

// 참고로 안돌려보고 여기에서 대충 만든거라 컴파일 에러날 확률이 매우 높습니다.
override fun getItemOffsets(outRect: Rect, view: View, parent: RecyclerView, state: RecyclerView.State) {
    super.getItemOffsets(outRect, view, parent, state)
    outRect.setEmpty()

    val position = parent.getChildAdapterPosition(view).takeIf { it != RecyclerView.NO_POSITION } ?: run {
        return
    }

    val space = 20.dp