I have a View which lists books (nodes). They are sorted by alphabetical order (Title). Good. They are linked to taxonomies (categories). I could sort by taxonomy to group books of the similar theme together, and a second sort by title. Good.
Now the problem. My client want to list both taxonomies (categories) names and title books together, so we have the following beautiful omellete of data (imagine that the lists which are book titles beggining with prefix "-" are hidden after you click on the taxonomy they belong):
Antologies (category) - Interesting antology (book) *hidden until you click Antologies* - More interesting antology (book) *hidden til you click Antologies* Book about everything the meaning of life (book) *visible* Cooking books (category) - A guide on cooking data (book) *hidden til you click Cooking books* - How to cook an alien (book) *hidden til you click Cooking books* Course of the pyramid (book) *visible* Decameron (book) *visible*
Nonetheless to say, I am completely at lost here. I have considered to use an extra field data to the content (node = book) to set an alias, which is the category. Then order by alias and to achieve the " - " indentation, use some hook code to identify the taxonomy.