javascript-React：setState无法获得预期的结果(不起作用？)

我的项目是Cordova React(es6).
我在使用setState()时遇到一些问题.

传递给状态的数据不为空.
但是,将数据传递给状态时,我收到的结果状态为空.

我项目的env(package.json)：

{
  "name": "MYAPP",
  "version": "1.0.0",
  "description": "this is front of simula's app",
  "main": "gulpfile.js",
  "scripts": {
    "test": "echo \"Error: no test specified\" && exit 1",
    "build": "browserify ./www/jsx/app.jsx -t babelify -o ./www/js/app.js"
  },
  "author": "maki",
  "license": "ISC",
  "dependencies": {
    "babel-preset-es2015": "^6.13.2",
    "browserify": "^13.1.0",
    "gulp": "^3.9.1",
    "history": "^4.2.0",
    "material-design-icons": "^2.2.3",
    "material-ui": "^0.15.4",
    "rd3": "^0.7.2",
    "react": "^15.3.0",
    "react-d3": "^0.4.0",
    "react-dom": "^15.3.1",
    "react-motion": "^0.4.4",
    "react-router": "^2.7.0",
    "react-swipeable-views": "^0.7.0",
    "react-tap-event-plugin": "^1.0.0",
    "vinyl-source-stream": "^1.1.0"
  },
  "devDependencies": {
    "babel-cli": "^6.11.4",
    "babel-plugin-transform-class-properties": "^6.11.5",
    "babel-preset-react": "^6.11.1",
    "babel-preset-stage-1": "^6.13.0",
    "babelify": "^7.3.0",
    "gulp-sass": "^2.3.2",
    "jquery": "^3.1.0"
  }
}

而我的代码：

export default class SomeCard extends React.Component {
  constructor(){
    super();

    this.state = {
      data_source: []
    }
  }

  componentDidMount(){
    const {name, data} = this.props.data;
    if(name == 'AAA'){
      let values_a = data.map((tmp_data) =>{
        let date = new Date(tmp_data.date);
        return {
          x: date,
          open: tmp_data.open,
          high: tmp_data.high,
          low: tmp_data.low,
          close: tmp_data.close
        };
      });
      let final_tmp_data = [
        {
          name: name,
          values: values_a
        }
      ];
      console.log(final_tmp_data);  //NOT EMPTY
      this.setState({data_source: final_tmp_data});
      console.log(data_source);     //NOT EMPTY
    }else if(name == 'BBB'){
      let values_b = data.map((tmp_data) => {
        let date = new Date(tmp_data.date);
        let tmp_date = date.getFullYear();
        return {
          "x": String(tmp_date),
          "y": tmp_data.value
        };
      });
      let final_cash_data = [
        {
          "name": name,
          "values": values_b
        }
      ];
      console.log(final_cash_data);          //NOT EMPTY
      this.setState({data_source: final_cash_data});
      console.log(this.state.data_source);   //EMPTY!!!!!!!!
    }
  .....
}

我该怎么办？？？

解决方法:

React setState()是异步操作,因此在您的代码中调用结果后,它不会立即传递结果.如果添加console.log(this.state.data_source),则可以访问更新后的状态.在render()方法中,此方法仅在this.setState()完成时调用.

看看React文档：https://facebook.github.io/react/docs/component-api.html#setstate

setState() does not immediately mutate this.state but creates a pending state transition. Accessing this.state after calling this method can potentially return the existing value.
There is no guarantee of synchronous operation of calls to setState and calls may be batched for performance gains.

setState() will always trigger a re-render unless conditional rendering logic is implemented in shouldComponentUpdate().