past value from parent in reactjs

1class ParentComponent extends React.Component {
2
3    state = { language: '' }
4
5    handleLanguage = (langValue) => {
6        this.setState({language: langValue});
7    }
8
9    render() {
10         return (
11                <div className="col-sm-9">
12                    <SelectLanguage onSelectLanguage={this.handleLanguage} /> 
13                </div>
14        )
15     }
16}
17

1var json = require("json!../languages.json");
2var jsonArray = json.languages;
3
4export class SelectLanguage extends React.Component {
5    state = {
6            selectedCode: '',
7            selectedLanguage: jsonArray[0],
8        }
9
10    handleLangChange = () => {
11        var lang = this.dropdown.value;
12        this.props.onSelectLanguage(lang);            
13    }
14
15    render() {
16        return (
17            <div>
18                <DropdownList ref={(ref) => this.dropdown = ref}
19                    data={jsonArray} 
20                    valueField='lang' textField='lang'
21                    caseSensitive={false} 
22                    minLength={3}
23                    filter='contains'
24                    onChange={this.handleLangChange} />
25            </div>            
26        );
27    }
28}
29