垂直进度条，thumb左侧显示不全

[chensenhua]

<style name="eq_seek_bar">
    <item name="android:layout_width">0dp</item>
    <item name="android:layout_height">match_parent</item>
    <item name="android:layout_weight">1</item>
    <item name="rsb_mode">single</item>
    <item name="rsb_min">-8</item>
    <item name="rsb_max">8</item>
    <item name="android:paddingTop">0dp</item>
    <item name="rsb_progress_radius">5dp</item>
    <item name="rsb_progress_height">4dp</item>
    <item name="rsb_thumb_width">24dp</item>
    <item name="rsb_thumb_height">24dp</item>

    <item name="rsb_progress_default_color">#ffe8e8e8</item>
    <item name="rsb_progress_color">@color/main_color_blue</item>

</style>

[chensenhua]

SeekBar 中的onDrawThumb(Canvas canvas)
canvas.drawBitmap(thumbBitmap, 0, rangeSeekBar.getProgressTop() + (rangeSeekBar.getProgressHeight() - scaleThumbHeight) / 2f, null);
的rangeSeekBar.getProgressHeight() 导致了thumb左偏移了，这里不应该把这个高度纳入计算，progress和thumd是层叠而不是并列的关系