lib/motion-kit/helpers/tree_layout.rb in motion-kit-0.13.0 vs lib/motion-kit/helpers/tree_layout.rb in motion-kit-0.14.0

@@ -285,9 +285,115 @@
         element = element.view
       end
       element
     end
 
+    # Search for a sibling: the next sibling that has the given id
+    def next(element_id)
+      self.next(element_id, from: target)
+    end
+
+    def next(element_id, from: from_view)
+      unless is_parent_layout?
+        return parent_layout.next(element_id, from: from_view)
+      end
+      search = @elements[element_id]
+      if search.nil? || search.empty?
+        return nil
+      end
+
+      if from_view.is_a?(NSString)
+        from_view = self.get(from_view)
+      end
+
+      if from_view.is_a?(ConstraintsTarget)
+        from_view = from_view.view
+      end
+
+      searching = false
+      found = nil
+      MotionKit.siblings(from_view).each do |sibling|
+        if sibling == from_view
+          searching = true
+        elsif searching && search.include?(sibling)
+          found = sibling
+          break
+        end
+      end
+      return found
+    end
+
+    # Search for a sibling: the previous sibling that has the given id
+    def prev(element_id)
+      prev(element_id, from: target)
+    end
+
+    def prev(element_id, from: from_view)
+      unless is_parent_layout?
+        return parent_layout.prev(element_id, from: from_view)
+      end
+
+      search = @elements[element_id]
+      if search.nil? || search.empty?
+        return nil
+      end
+
+      if from_view.is_a?(NSString)
+        from_view = self.get(from_view)
+      end
+
+      if from_view.is_a?(ConstraintsTarget)
+        from_view = from_view.view
+      end
+
+      found = nil
+      MotionKit.siblings(from_view).each do |sibling|
+        if sibling == from_view
+          break
+        elsif search.include?(sibling)
+          # keep searching; prev should find the *closest* matching view
+          found = sibling
+        end
+      end
+      return found
+    end
+
+    # This searches for the "nearest" view with a given id.  First, all child
+    # views are checked.  Then the search goes up to the parent view, and its
+    # child views are checked.  This means *any* view that is in the parent
+    # view's hierarchy is considered closer than a view in a grandparent's
+    # hierarchy.  This is a "depth-first" search, so any subview that contains
+    # a view with the element id
+    #
+    # A--B--C--D*   Starting at D, E is closer than F, because D&E are siblings.
+    #  \  \  \-E    But F, G and H are closer than A or I, because they share a
+    #   \  \-F--G   closer *parent* (B).  The logic is, "B" is a container, and
+    #    \-I  \-H   all views in that container are in a closer family.
+    def nearest(element_id)
+      nearest(element_id, from: target)
+    end
+
+    def nearest(element_id, from: from_view)
+      unless is_parent_layout?
+        return parent_layout.nearest(element_id, from: from_view)
+      end
+
+      search = @elements[element_id]
+      if search.nil? || search.empty?
+        return nil
+      end
+
+      if from_view.is_a?(NSString)
+        from_view = self.get(from_view)
+      end
+
+      if from_view.is_a?(ConstraintsTarget)
+        from_view = from_view.view
+      end
+
+      MotionKit.nearest(from_view) { |test_view| search.include?(test_view) }
+    end
+
     # Removes a view (or several with the same name) from the hierarchy
     # and forgets it entirely.  Returns the views that were removed.
     def remove(element_id)
       unless is_parent_layout?
         return parent_layout.remove(element_id)