--- order: 99 debug: true title: zh-CN: 嵌套 en-US: Nest --- ## zh-CN 默认选中第一项。 ## en-US Default activate first tab. ```jsx import { Tabs, Select } from 'antd'; const { TabPane } = Tabs; const { Option } = Select; const positionList = ['left', 'right', 'top', 'bottom']; const list = new Array(20).fill().map((_, index) => index); class Demo extends React.Component { state = { parentPos: undefined, childPos: undefined, parentType: undefined, childType: undefined, }; render() { const { parentPos, childPos, parentType, childType } = this.state; return (