openseadragon_helper.rb in blacklight-gallery-4.0.0

- old
+ new

@@ -1,7 +1,24 @@
 module Blacklight
   module OpenseadragonHelper
+    # Somewhat arbitrary number; the only important thing is that
+    # it is bigger than the number of embedded viewers on a page
+    ID_COUNTER_MAX = (2**20) - 1
+
+    # Mint a (sufficiently) unique identifier, so we can associate
+    # the expand/collapse control with labels
+    def self.mint_id
+      @id_counter = ((@id_counter || 0) + 1) % ID_COUNTER_MAX
+
+      # We convert the ID to hex for markup compactness
+      @id_counter.to_s(16)
+    end
+
     def osd_container_class
       "col-md-6"
     end
+
+    def osd_html_id_prefix
+      "osd-#{Blacklight::OpenseadragonHelper.mint_id}".to_param
+    end
   end
-end
\ No newline at end of file
+end