[code] add comment

Runtime/Theme/AxisTheme.cs

@@ -122,7 +122,10 @@ namespace XCharts.Runtime
             get { return m_TickColor; }
             set { if (PropertyUtil.SetColor(ref m_TickColor, value)) SetVerticesDirty(); }
         }
-
+        /// <summary>
+        /// the colors of split area.
+        /// |坐标轴分隔区域的颜色。
+        /// </summary>
         public List<Color32> splitAreaColors
         {
             get { return m_SplitAreaColors; }

Runtime/Theme/SerieTheme.cs

@@ -27,18 +27,38 @@ namespace XCharts.Runtime
             get { return m_LineWidth; }
             set { if (PropertyUtil.SetStruct(ref m_LineWidth, value)) SetVerticesDirty(); }
         }
+        /// <summary>
+        /// the symbol size of line serie.
+        /// |折线图的Symbol大小。
+        /// </summary>
         public float lineSymbolSize
         {
             get { return m_LineSymbolSize; }
             set { if (PropertyUtil.SetStruct(ref m_LineSymbolSize, value)) SetVerticesDirty(); }
         }
+        /// <summary>
+        /// the selected symbol size of line serie.
+        /// |折线图Symbol在被选中状态时的大小。
+        /// </summary>
         public float lineSymbolSelectedSize { get { return lineSymbolSize * selectedRate; } }
+        /// <summary>
+        /// the symbol size of scatter serie.
+        /// |散点图的Symbol大小。
+        /// </summary>
         public float scatterSymbolSize
         {
             get { return m_ScatterSymbolSize; }
             set { if (PropertyUtil.SetStruct(ref m_ScatterSymbolSize, value)) SetVerticesDirty(); }
         }
+        /// <summary>
+        /// the selected symbol size of scatter serie.
+        /// |散点图的Symbol在被选中状态时的大小。
+        /// </summary>
         public float scatterSymbolSelectedSize { get { return scatterSymbolSize * selectedRate; } }
+        /// <summary>
+        /// the rate of symbol size of line or scatter serie.
+        /// |折线图或散点图在被选中时的放大倍数。
+        /// </summary>
         public float selectedRate
         {
             get { return m_SelectedRate; }
@@ -46,7 +66,8 @@ namespace XCharts.Runtime
         }
 
         /// <summary>
-        /// 饼图鼠标移到高亮时的额外半径
+        /// the extra radius of pie when actived by tooltip.
+        /// |饼图鼠标移到高亮时的额外半径
         /// </summary>
         public float pieTooltipExtraRadius
         {
@@ -54,7 +75,8 @@ namespace XCharts.Runtime
             set { if (PropertyUtil.SetStruct(ref m_PieTooltipExtraRadius, value < 0 ? 0f : value)) SetVerticesDirty(); }
         }
         /// <summary>
-        /// 饼图选中时的中心点偏移
+        /// the center offset of pie if selected.
+        /// |饼图选中时的中心点偏移。
         /// </summary>
         public float pieSelectedOffset
         {

Runtime/Theme/ThemeStyle.cs

@@ -58,17 +58,23 @@ namespace XCharts.Runtime
         {
             get { return sharedTheme.themeType; }
         }
+        /// <summary>
+        /// theme name.
+        /// |主题名字。
+        /// </summary>
         public string themeName
         {
             get { return sharedTheme.themeName; }
         }
-
+        /// <summary>
+        /// the asset of theme.
+        /// |主题配置。
+        /// </summary>
         public Theme sharedTheme
         {
             get { return m_SharedTheme; }
             set { m_SharedTheme = value; SetAllDirty(); }
         }
-
         /// <summary>
         /// the contrast color of chart.
         /// |对比色。
@@ -91,7 +97,7 @@ namespace XCharts.Runtime
         }
         /// <summary>
         /// Whether the background color is transparent. When true, the background color is not drawn.
-        /// ｜是否透明背景颜色。当设置为true时，不绘制背景颜色。
+        /// |是否透明背景颜色。当设置为true时，不绘制背景颜色。
         /// </summary>
         public bool transparentBackground
         {