Merge "Make scroll bars more noticeable on round screens."

    private static final int MAX_SCROLLBAR_ANGLE_SWIPE = 16;

    private static final int MIN_SCROLLBAR_ANGLE_SWIPE = 6;

    private static final float WIDTH_PERCENTAGE = 0.02f;

    private static final int DEFAULT_THUMB_COLOR = 0x4CFFFFFF;

    private static final int DEFAULT_TRACK_COLOR = 0x26FFFFFF;

    private static final int DEFAULT_THUMB_COLOR = 0xFFE8EAED;

    private static final int DEFAULT_TRACK_COLOR = 0x4CFFFFFF;

    private final Paint mThumbPaint = new Paint();

    private final Paint mTrackPaint = new Paint();

    private final RectF mRect = new RectF();

    private final View mParent;

    private final int mMaskThickness;

    public RoundScrollbarRenderer(View parent) {

        // Paints for the round scrollbar.

        mTrackPaint.setStyle(Paint.Style.STROKE);

        mParent = parent;

        // Fetch the resource indicating the thickness of CircularDisplayMask, rounding in the same

        // way WindowManagerService.showCircularMask does. The scroll bar is inset by this amount so

        // that it doesn't get clipped.

        mMaskThickness = parent.getContext().getResources().getDimensionPixelSize(

                com.android.internal.R.dimen.circular_display_mask_thickness);

    }

    public void drawRoundScrollbars(Canvas canvas, float alpha, Rect bounds) {

        startAngle = clamp(startAngle, -SCROLLBAR_ANGLE_RANGE / 2,

                SCROLLBAR_ANGLE_RANGE / 2 - sweepAngle);

        // Draw the track and the scroll bar.

        // Draw the track and the thumb.

        float inset = thumbWidth / 2 + mMaskThickness;

        mRect.set(

                bounds.left - thumbWidth / 2,

                bounds.top,

                bounds.right - thumbWidth / 2,

                bounds.bottom);

                bounds.left + inset,

                bounds.top + inset,

                bounds.right - inset,

                bounds.bottom - inset);

        canvas.drawArc(mRect, -SCROLLBAR_ANGLE_RANGE / 2, SCROLLBAR_ANGLE_RANGE, false,

                mTrackPaint);

        canvas.drawArc(mRect, startAngle, sweepAngle, false, mThumbPaint);