saleor-dashboard/src/components/Tab/Tabs.tsx

import React from "react";

export interface TabsProps {
  children: (props: {
    changeTab: (index: number) => void;
    currentTab: number;
  }) => React.ReactNode;
}

interface TabsState {
  currentTab: number;
}

class Tabs extends React.Component<TabsProps, TabsState> {
  state: TabsState = {
    currentTab: 0,
  };

  changeTab = (index: number) => this.setState({ currentTab: index });

  render() {
    return this.props.children({
      changeTab: this.changeTab,
      currentTab: this.state.currentTab,
    });
  }
}

export default Tabs;