[Improvement] Button: add text prop (#563)

docs/markdown/en-US/button.md

@@ -69,6 +69,7 @@ Use `tag` prop to custom button tag
 |-----------|-----------|-----------|-------------|-------------|
 | type | Type | `String` | `default` | `primary` `danger` |
 | size | Size | `String` | `normal` | `large` `small` `mini` |
+| text | Text | `String` | - | - |
 | tag | Tag | `String` | `button` | - |
 | native-type | Native Type Attribute | `String` | `''` | - |
 | disabled | Whether disable button | `Boolean` | `false` | - |

docs/markdown/zh-CN/button.md

@@ -73,8 +73,9 @@ Vue.use(Button);
 |-----------|-----------|-----------|-------------|-------------|
 | type | 按钮类型 | `String` | `default` | `primary` `danger` |
 | size | 按钮尺寸 | `String` | `normal` | `large` `small` `mini` |
+| text | 按钮文字 | `String` | - | - |
 | tag | 按钮标签 | `String` | `button` | 任意`HTML`标签 |
-| native-type | 按钮类型（原生） | `String` | `''` | - |
+| native-type | 按钮类型（原生） | `String` | - | - |
 | disabled | 是否禁用 | `Boolean` |  `false` | - |
 | loading | 是否显示为加载状态 | `Boolean` |  `false` | - |
 | block | 是否为块级元素 | `Boolean` |   `false` | - |

packages/button/index.vue

@@ -23,7 +23,7 @@
       :color="type === 'default' ? 'black' : 'white'"
     />
     <span class="van-button__text">
-      <slot />
+      <slot>{{ text }}</slot>
     </span>
   </component>
 </template>
@@ -35,6 +35,7 @@ export default create({
   name: 'van-button',
 
   props: {
+    text: String,
     block: Boolean,
     loading: Boolean,
     disabled: Boolean,

packages/dialog/dialog.vue

@@ -50,14 +50,11 @@ export default create({
     callback: Function,
     confirmButtonText: String,
     cancelButtonText: String,
+    showCancelButton: Boolean,
     showConfirmButton: {
       type: Boolean,
       default: true
     },
-    showCancelButton: {
-      type: Boolean,
-      default: false
-    },
     overlay: {
       type: Boolean,
       default: true