React JS onClick 이벤트 핸들러

React JS onClick 이벤트 핸들러

---

나는 가지고있다

var TestApp = React.createClass({
      getComponent: function(){
          console.log(this.props);
      },
      render: function(){
        return(
             <div>
             <ul>
                <li onClick={this.getComponent}>Component 1</li>
             </ul>
             </div>
        );
      }
});
React.renderComponent(<TestApp />, document.body);

클릭 한 목록 요소의 배경에 색을 지정하고 싶습니다. React에서 어떻게 할 수 있습니까?

같은 것

$('li').on('click', function(){
    $(this).css({'background-color': '#ccc'});
});

---

왜 안 되는가 :

onItemClick: function (event) {

    event.currentTarget.style.backgroundColor = '#ccc';

},

render: function() {
    return (
        <div>
            <ul>
                <li onClick={this.onItemClick}>Component 1</li>
            </ul>
        </div>
    );
}

그리고 그것에 대해 더 많은 반응을 보이고 싶다면 선택된 항목을 포함하는 React 구성 요소의 상태로 설정 한 다음 해당 상태를 참조하여 다음 내 항목의 색상을 결정할 수 있습니다 render.

onItemClick: function (event) {

    this.setState({ selectedItem: event.currentTarget.dataset.id });
    //where 'id' =  whatever suffix you give the data-* li attribute
},

render: function() {
    return (
        <div>
            <ul>
                <li onClick={this.onItemClick} data-id="1" className={this.state.selectedItem == 1 ? "on" : "off"}>Component 1</li>
                <li onClick={this.onItemClick} data-id="2" className={this.state.selectedItem == 2 ? "on" : "off"}>Component 2</li>
                <li onClick={this.onItemClick} data-id="3" className={this.state.selectedItem == 3 ? "on" : "off"}>Component 3</li>
            </ul>
        </div>
    );
},

물론 이러한 <li>s를 루프 에 넣고 싶을 것이며 li.on및 li.off스타일을 background-color.

---

내가 생각할 수있는 두 가지 방법은

var TestApp = React.createClass({
    getComponent: function(index) {
        $(this.getDOMNode()).find('li:nth-child(' + index + ')').css({
            'background-color': '#ccc'
        });
    },
    render: function() {
        return (
            <div>
              <ul>
                <li onClick={this.getComponent.bind(this, 1)}>Component 1</li>
                <li onClick={this.getComponent.bind(this, 2)}>Component 2</li>
                <li onClick={this.getComponent.bind(this, 3)}>Component 3</li>
              </ul>
            </div>
        );
    }
});
React.renderComponent(<TestApp /> , document.getElementById('soln1'));

이것은 제가 개인적으로 가장 좋아하는 것입니다.

var ListItem = React.createClass({
    getInitialState: function() {
        return {
            isSelected: false
        };
    },
    handleClick: function() {
        this.setState({
            isSelected: true
        })
    },
    render: function() {
        var isSelected = this.state.isSelected;
        var style = {
            'background-color': ''
        };
        if (isSelected) {
            style = {
                'background-color': '#ccc'
            };
        }
        return (
            <li onClick={this.handleClick} style={style}>{this.props.content}</li>
        );
    }
});

var TestApp2 = React.createClass({
    getComponent: function(index) {
        $(this.getDOMNode()).find('li:nth-child(' + index + ')').css({
            'background-color': '#ccc'
        });
    },
    render: function() {
        return (
            <div>
             <ul>
              <ListItem content="Component 1" />
              <ListItem content="Component 2" />
              <ListItem content="Component 3" />
             </ul>
            </div>
        );
    }
});
React.renderComponent(<TestApp2 /> , document.getElementById('soln2'));

여기 데모입니다

이게 도움이 되길 바란다.

---

다음은 es6 구문을 사용하여 질문 제목에 대답 하는 react onClick 이벤트 핸들러 를 정의하는 방법입니다.

import React, { Component } from 'react';

export default class Test extends Component {
  handleClick(e) {
    e.preventDefault()
    console.log(e.target)
  }

  render() {
    return (
      <a href='#' onClick={e => this.handleClick(e)}>click me</a>
    )
  }
}

---

ECMA2015를 사용하십시오. 화살표 기능은 "this"를 훨씬 더 직관적으로 만듭니다.

import React from 'react';


class TestApp extends React.Component {
   getComponent(e, index) {
       $(e.target).css({
           'background-color': '#ccc'
       });
   }
   render() {
       return (
           <div>
             <ul>
               <li onClick={(e) => this.getComponent(e, 1)}>Component 1</li>
               <li onClick={(e) => this.getComponent(e, 2)}>Component 2</li>
               <li onClick={(e) => this.getComponent(e, 3)}>Component 3</li>
             </ul>
           </div>
       );
   }
});
React.renderComponent(<TestApp /> , document.getElementById('soln1'));`

---

ES6를 사용하는 경우 다음은 몇 가지 간단한 예제 코드입니다.

import React from 'wherever_react_is';

class TestApp extends React.Component {

  getComponent(event) {
      console.log('li item clicked!');
      event.currentTarget.style.backgroundColor = '#ccc';
  }

  render() {
    return(
       <div>
         <ul>
            <li onClick={this.getComponent.bind(this)}>Component 1</li>
         </ul>
       </div>
    );
  }
}

export default TestApp;

ES6 클래스 본문에서 함수는 더 이상 'function'키워드를 필요로하지 않으며 쉼표로 구분할 필요가 없습니다. 원하는 경우 => 구문을 사용할 수도 있습니다.

다음은 동적으로 생성 된 요소가있는 예입니다.

import React from 'wherever_react_is';

class TestApp extends React.Component {

constructor(props) {
  super(props);

  this.state = {
    data: [
      {name: 'Name 1', id: 123},
      {name: 'Name 2', id: 456}
    ]
  }
}

  getComponent(event) {
      console.log('li item clicked!');
      event.currentTarget.style.backgroundColor = '#ccc';
  }

  render() {        
       <div>
         <ul>
         {this.state.data.map(d => {
           return(
              <li key={d.id} onClick={this.getComponent.bind(this)}>{d.name}</li>
           )}
         )}
         </ul>
       </div>
    );
  }
}

export default TestApp;

동적으로 생성 된 각 요소에는 고유 한 참조 '키'가 있어야합니다.

또한 이벤트가 아닌 실제 데이터 개체를 onClick 함수에 전달하려면이를 바인딩에 전달해야합니다. 예를 들면 :

새로운 onClick 기능 :

getComponent(object) {
    console.log(object.name);
}

데이터 개체 전달 :

{this.state.data.map(d => {
    return(
      <li key={d.id} onClick={this.getComponent.bind(this, d)}>{d.name}</li>
    )}
)}

---

와 이벤트 처리 요소에 반응하는 DOM 요소의 이벤트를 처리하는 매우 유사하다. 몇 가지 구문 차이가 있습니다.

• React 이벤트는 소문자가 아닌 camelCase를 사용하여 이름이 지정됩니다.
• With JSX you pass a function as the event handler, rather than a string.

So as mentioned in React documentation, they quite similar to normal HTML when it comes to Event Handling, but event names in React using camelcase, because they are not really HTML, they are JavaScript, also, you pass the function while we passing function call in a string format for HTML, they are different, but the concepts are pretty similar...

Look at the example below, pay attention to the way event get passed to the function:

function ActionLink() {
  function handleClick(e) {
    e.preventDefault();
    console.log('The link was clicked.');
  }

  return (
    <a href="#" onClick={handleClick}>
      Click me
    </a>
  );
}

---

import React from 'react';

class MyComponent extends React.Component {

  getComponent(event) {
      event.target.style.backgroundColor = '#ccc';
      
      // or you can write
      //arguments[0].target.style.backgroundColor = '#ccc';
  }

  render() {
    return(
       <div>
         <ul>
            <li onClick={this.getComponent.bind(this)}>Component 1</li>
         </ul>
       </div>
    );
  }
}

export { MyComponent };  // use this to be possible in future imports with {} like: import {MyComponent} from './MyComponent'
export default MyComponent;

---

You can make use of the React.createClone method. Create your element, than create a clone of it. During the clone's creation, you can inject props. Inject an onClick : method prop like this

{ onClick : () => this.changeColor(originalElement, index) }

the changeColor method will set the state with the duplicate, allowing you sto set the color in the process.

render()
  {
    return(
      <ul>

        {this.state.items.map((val, ind) => {
          let item = <li key={ind}>{val}</li>;
          let props = { 
            onClick: () => this.Click(item, ind),
            key : ind,
            ind
          }
          let clone = React.cloneElement(item, props, [val]);
          return clone;
        })}

      </ul>
    )
  }

---

Please comment if you downvote. This is a non-standard (but not so uncommon) React pattern that doesn't use JSX, instead putting everything inline. Also, it's Coffeescript.

The 'React-way' to do this would be with the component's own state:

(c = console.log.bind console)

mock_items: [
    {
        name: 'item_a'
        uid: shortid()
    }
    {
        name: 'item_b'
        uid: shortid()
    }
    {
        name: 'item_c'
        uid: shortid()
    }
]
getInitialState: ->
    lighted_item: null
render: ->
    div null,
        ul null,
            for item, idx in @mock_items
                uid = item.uid
                li
                    key: uid
                    onClick: do (idx, uid) =>
                        (e) =>
                            # justf to illustrate these are bound in closure by the do lambda,
                            c idx
                            c uid
                            @setState
                                lighted_item: uid
                    style:
                        cursor: 'pointer'
                        background: do (uid) =>
                            c @state.lighted_item
                            c 'and uid', uid
                            if @state.lighted_item is uid then 'magenta' else 'chartreuse'
                        # background: 'chartreuse'
                    item.name

This example works -- I tested it locally. You can check out this example code exactly at my github. Originally the env was only local for my own whiteboard r&d purposes but I posted it to Github for this. It may get written over at some point but you can check out the commit from Sept 8, 2016 to see this.

More generally, if you want to see how this CS/no-JSX pattern for React works, check out some recent work here. It's possible I will have time to fully implement a POC for this app idea, the stack for which includes NodeJS, Primus, Redis, & React.

참고URL : https://stackoverflow.com/questions/28511207/react-js-onclick-event-handler