Saw the sample - Coloring of tags and parameters looks good.
Current requirement is a basic one. So we need:
- Underlining of invalid tags (closing not matching opening)
- Automatic tag closing: As soon as a tag is typed, the closing tag is automatically inserted. Optionally, when a parameter is typed with a quotation mark, the closing quotation mark is automatically inserted.
- Pretty Print: The editor can convert any xml into properly formatted xml with cr/lf and indentation.