[new feature] NavBar: add border prop (#2143)

packages/nav-bar/en-US.md

@@ -53,6 +53,7 @@ export default {
 | right-text | Right Text | `String` | `''` |
 | left-arrow | Whether to show left arrow | `Boolean` | `false` |
 | fixed | Whether to fixed top | `Boolean` | `false` |
+| border | Whether to show bottom border | `Boolean` | `true` |
 | z-index | Z-index | `Number` | `1` |
 
 ### Slot

packages/nav-bar/index.vue

@@ -1,7 +1,6 @@
 <template>
   <div
-    class="van-hairline--bottom"
+    :class="[b({ fixed }), { 'van-hairline--bottom': border }]"
-    :class="b({ fixed })"
     :style="style"
   >
     <div
@@ -50,10 +49,14 @@ export default create({
 
   props: {
     title: String,
+    fixed: Boolean,
     leftText: String,
     rightText: String,
     leftArrow: Boolean,
-    fixed: Boolean,
+    border: {
+      type: Boolean,
+      default: true
+    },
     zIndex: {
       type: Number,
       default: 1

packages/nav-bar/zh-CN.md

@@ -54,6 +54,7 @@ export default {
 | right-text | 右侧文案 | `String` | `''` | - |
 | left-arrow | 是否显示左侧箭头 | `Boolean` | `false` | - |
 | fixed | 是否固定在顶部 | `Boolean` | `false` | - |
+| border | 是否显示下边框 | `Boolean` | `true` | 1.4.7 |
 | z-index | 元素 z-index | `Number` | `1` | - |
 
 ### Slot