реагировать состояние переключения
this.setState(prevState => ({
iover: prevState.iover === 'hide' ? 'show' : 'hide'
}));
Elegant Eagle
this.setState(prevState => ({
iover: prevState.iover === 'hide' ? 'show' : 'hide'
}));
this.setState(prevState => ({
check: !prevState.check
}));this.setState(prevState => ({
iover: !prevState.iover
}));