Desktop React component with state-based modal

gistfile1.js

const editSubjects = Symbol('editSubjectStateCollection');
class BookViewListDesktop extends React.Component{
    constructor(){
        super();
        this.state = {
            booksSubjectsModalShown: false,
            editSubjectsFor: [],
            subjectsAdding: [],
            subjectsRemoving: []
        };
    }
    closeEditBooksSubjectsModal(){
        this.setState({ booksSubjectsModalShown: false });
    }
    singleBookSubjectsModal(book){
        this.setState({
            booksSubjectsModalShown: true,
            editSubjectsFor: [book],
            subjectsAdding: [],
            subjectsRemoving: []
        });
    }
    multiBookSubjectsModal(){
        this.setState({
            booksSubjectsModalShown: true,
            editSubjectsFor: this.props.bookList.filter(b => b.selected),
            subjectsAdding: [],
            subjectsRemoving: []
        });
    }
    toggleAddSubjectPending(subject, toggledOn){
        this[editSubjects](subject, toggledOn, 'subjectsAdding');
    }
    toggleRemoveSubjectPending(subject, toggledOn){
        this[editSubjects](subject, toggledOn, 'subjectsRemoving');
    }
    [editSubjects](subject, toggledOn, stateName){
        let updated = this.state[stateName].concat();
        if (toggledOn){
            updated.push(subject);
        } else {
            updated = updated.filter(s => s._id !== subject._id);
        }
        this.setState({ [stateName]: updated });
    }
}