19강. 이벤트 state props 그리고 render 함수 class App extends Component{ constructor(props){ super(props); this.state = { // //읽기, 클릭 구분을 위한 mode mode:'welcome', subject:{title:"WEB", sub:"World wide Web!"}, welcome:{title:"welcome", desc:"Hello, React!"}, // contents:[ {id:1, title:'HTML', desc: 'HTML is ..'}, {id:2, title:'CSS', desc: 'CSS is ..'}, {id:3, title:'JS', desc: 'JS is ..'} ] } } //↑ props o..