Implementation for a SearchField class
BaseApiCompat implementation for compatibility to the old
`getSearchFields()` implementation
Move different types of searchfields to subclasses
Add "advanced" property to search fields
Starting to implement new SearchField UI
Continuing to implement new SearchField UI
Add "order" as a search field constant to OpacApi
Sort search fields correctly in BaseApiCompat implementation
Implement Dropdown search fields and run getSearchFields()
asynchronously
Make loadQuery() work again
Make BaseApiCompat's getSearchFields faster when Metadata is already
loaded
Remove unused loadMetaData things in SearchFragment
Add ProgressBar when loading search fields
Don't show advanced search fields when they aren't selected in settings
rewrite clear() function
Re-enable barcode scanning with new SearchFields implementation
Remove unused imports
Rename "manageVisibility" to "buildSearchForm" because we don't manage
visibilities there anymore ;)
Make BaseApiCompat sort the fields correctly
Support half-width search fields