### 基本用法

``` html
<u-dropdown>
    <template #title><u-text text="下拉菜单"></u-text></template>
    <u-dropdown-item text="选项一"></u-dropdown-item>
    <u-dropdown-item text="选项二"></u-dropdown-item>
    <u-dropdown-item text="选项三"></u-dropdown-item>
</u-dropdown>
```

## 按钮样式

``` html
<u-dropdown type="primary">
    <template #title><u-text text="下拉按钮"></u-text></template>
    <u-dropdown-item text="选项一"></u-dropdown-item>
    <u-dropdown-item text="选项二"></u-dropdown-item>
    <u-dropdown-item text="选项三"></u-dropdown-item>
</u-dropdown>
```
