Codeview highlighted

[CFdong]

When I click the codeview, the codes is no highlighted. What should I do to achieve it? Thanks!

<ReactSummernote
value={descriptionValueLong}
className="react-summernote"
codemirror={ // codemirror options
{ theme: 'monokai' }
}
options={{
toolbar: [
['style', ['style']],
['font', ['bold', 'underline', 'clear']],
['fontname', ['fontname']],
['color', ['color']],
['para', ['ul', 'ol', 'paragraph']],
['table', ['table']],
['insert', ['link', 'picture', 'video']],
['view', ['fullscreen', 'codeview', 'help']],
]
}}
onChange={descriptionChangeLong}
/>

[CFdong]