Merge "Update specs for scrollbar" into main

import static java.lang.Math.sin;

import android.content.res.Resources;

import android.graphics.Canvas;

import android.graphics.Color;

import android.graphics.Paint;

    // The range of the scrollbar position represented as an angle in degrees.

    private static final float SCROLLBAR_ANGLE_RANGE = 28.8f;

    private static final float MAX_SCROLLBAR_ANGLE_SWIPE = 26.3f; // 90%

    private static final float MIN_SCROLLBAR_ANGLE_SWIPE = 3.1f; // 10%

    private static final float THUMB_WIDTH_DP = 4f;

    private static final float MAX_SCROLLBAR_ANGLE_SWIPE = 0.7f * SCROLLBAR_ANGLE_RANGE;

    private static final float MIN_SCROLLBAR_ANGLE_SWIPE = 0.3f * SCROLLBAR_ANGLE_RANGE;

    private static final float GAP_BETWEEN_TRACK_AND_THUMB_DP = 3f;

    private static final float OUTER_PADDING_DP = 2f;

    private static final int DEFAULT_THUMB_COLOR = 0xFFFFFFFF;

    private static final int DEFAULT_TRACK_COLOR = 0x4CFFFFFF;

    private final RectF mRect = new RectF();

    private final View mParent;

    private final float mInset;

    private final float mGapBetweenThumbAndTrackPx;

    private final boolean mUseRefactoredRoundScrollbar;

    private float mPreviousMaxScroll = 0;

    private float mMaxScrollDiff = 0;

    private float mPreviousCurrentScroll = 0;

    private float mCurrentScrollDiff = 0;

    private float mThumbStrokeWidthAsDegrees = 0;

    private float mGapBetweenTrackAndThumbAsDegrees = 0;

    private boolean mDrawToLeft;

    private boolean mUseRefactoredRoundScrollbar;

    public RoundScrollbarRenderer(View parent) {

        // Paints for the round scrollbar.

        mParent = parent;

        Resources resources = parent.getContext().getResources();

        // 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.

        int maskThickness =

                parent.getContext()

                        .getResources()

                        .getDimensionPixelSize(

                resources.getDimensionPixelSize(

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

        float thumbWidth = dpToPx(THUMB_WIDTH_DP);

        float thumbWidth =

                resources.getDimensionPixelSize(com.android.internal.R.dimen.round_scrollbar_width);

        mGapBetweenThumbAndTrackPx = dpToPx(GAP_BETWEEN_TRACK_AND_THUMB_DP);

        mThumbPaint.setStrokeWidth(thumbWidth);

        mTrackPaint.setStrokeWidth(thumbWidth);

        mInset = thumbWidth / 2 + maskThickness;

        }

    }

    /** Returns true if horizontal bounds are updated */

    private void updateBounds(Rect bounds) {

        mRect.set(

                bounds.left + mInset,

                bounds.bottom - mInset);

        mThumbStrokeWidthAsDegrees =

                getVertexAngle((mRect.right - mRect.left) / 2f, mThumbPaint.getStrokeWidth() / 2f);

        mGapBetweenTrackAndThumbAsDegrees =

                getVertexAngle((mRect.right - mRect.left) / 2f, mGapBetweenThumbAndTrackPx);

    }

    private float computeSweepAngle(float scrollExtent, float maxScroll) {

                // The highest point of the top track on a vertical scale. Here the thumb width is

                // reduced to account for the arc formed by ROUND stroke style

                -SCROLLBAR_ANGLE_RANGE / 2f - mThumbStrokeWidthAsDegrees,

                // The lowest point of the top track on a vertical scale. Here the thumb width is

                // reduced twice to (a) account for the arc formed by ROUND stroke style (b) gap

                // between thumb and top track

                thumbStartAngle - mThumbStrokeWidthAsDegrees * 2,

                // The lowest point of the top track on a vertical scale. It's reduced by

                // (a) angular distance for the arc formed by ROUND stroke style

                // (b) gap between thumb and top track

                thumbStartAngle - mThumbStrokeWidthAsDegrees - mGapBetweenTrackAndThumbAsDegrees,

                alpha);

        // Draws the thumb

        drawArc(canvas, thumbStartAngle, thumbSweepAngle, mThumbPaint);

        // Draws the bottom arc

        drawTrack(

                canvas,

                // The highest point of the bottom track on a vertical scale. Here the thumb width

                // is added twice to (a) account for the arc formed by ROUND stroke style (b) gap

                // between thumb and bottom track

                (thumbStartAngle + thumbSweepAngle) + mThumbStrokeWidthAsDegrees * 2,

                // The highest point of the bottom track on a vertical scale. Following added to it

                // (a) angular distance for the arc formed by ROUND stroke style

                // (b) gap between thumb and top track

                (thumbStartAngle + thumbSweepAngle)

                        + mThumbStrokeWidthAsDegrees

                        + mGapBetweenTrackAndThumbAsDegrees,

                // The lowest point of the top track on a vertical scale. Here the thumb width is

                // added to account for the arc formed by ROUND stroke style

                SCROLLBAR_ANGLE_RANGE / 2f + mThumbStrokeWidthAsDegrees,

<?xml version="1.0" encoding="utf-8"?>

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  ~ Licensed under the Apache License, Version 2.0 (the "License");

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  -->

<resources>

    <!-- The width of the round scrollbar -->

    <dimen name="round_scrollbar_width">6dp</dimen>

</resources>

         aliasing effects). This is only used on circular displays. -->

    <dimen name="circular_display_mask_thickness">1px</dimen>

    <!-- The width of the round scrollbar -->

    <dimen name="round_scrollbar_width">5dp</dimen>

    <dimen name="lock_pattern_dot_line_width">22dp</dimen>

    <dimen name="lock_pattern_dot_size">14dp</dimen>

    <dimen name="lock_pattern_dot_size_activated">30dp</dimen>

  <java-symbol type="dimen" name="accessibility_magnification_indicator_width" />

  <java-symbol type="dimen" name="circular_display_mask_thickness" />

  <java-symbol type="dimen" name="user_icon_size" />

  <java-symbol type="dimen" name="round_scrollbar_width" />

  <java-symbol type="string" name="add_account_button_label" />

  <java-symbol type="string" name="addToDictionary" />