Merge pull request #256 from adamharrison/FixTabDragging

Allows you to drag nodes around splits.

data/core/rootview.lua

@@ -129,14 +129,14 @@ function Node:split(dir, view, locked, resizable)
   return self.b
 end
 
-
+function Node:remove_view(root, view)
-function Node:close_view(root, view)
-  local new_active_view = view == self.active_view
-  local do_close = function()
   if #self.views > 1 then
     local idx = self:get_view_idx(view)
+    if idx < self.tab_offset then
+      self.tab_offset = self.tab_offset - 1
+    end
     table.remove(self.views, idx)
-      if new_active_view then
+    if self.active_view == view then
       self:set_active_view(self.views[idx] or self.views[#self.views])
     end
   else
@@ -160,6 +160,11 @@ function Node:close_view(root, view)
   end
   core.last_active_view = nil
 end
+
+function Node:close_view(root, view)
+  local do_close = function()
+    self:remove_view(root, view)
+  end
   view:try_close(do_close)
 end
 
@@ -169,13 +174,13 @@ function Node:close_active_view(root)
 end
 
 
-function Node:add_view(view)
+function Node:add_view(view, idx)
   assert(self.type == "leaf", "Tried to add view to non-leaf node")
   assert(not self.locked, "Tried to add view to locked node")
   if self.views[1] and self.views[1]:is(EmptyView) then
     table.remove(self.views)
   end
-  table.insert(self.views, view)
+  table.insert(self.views, idx or (#self.views + 1), view)
   self:set_active_view(view)
 end
 
@@ -749,7 +754,7 @@ function RootView:on_mouse_pressed(button, x, y, clicks)
     if button == "middle" or node.hovered_close == idx then
       node:close_view(self.root_node, node.views[idx])
     else
-      self.dragged_node = idx
+      self.dragged_node = { node, idx }
       node:set_active_view(node.views[idx])
     end
   else
@@ -816,14 +821,26 @@ function RootView:on_mouse_moved(x, y, dx, dy)
     end
   elseif tab_index then
     core.request_cursor("arrow")
-    if self.dragged_node and self.dragged_node ~= tab_index then
+  elseif node then
-      local tab = node.views[self.dragged_node]
+    core.request_cursor(node.active_view.cursor)
-      table.remove(node.views, self.dragged_node)
+  end
-      table.insert(node.views, tab_index, tab)
+  if node and self.dragged_node and (self.dragged_node[1] ~= node or (tab_index and self.dragged_node[2] ~= tab_index))
-      self.dragged_node = tab_index
+    and node.type == "leaf" and #node.views > 0 and node.views[1]:is(DocView) then 
+      local tab = self.dragged_node[1].views[self.dragged_node[2]]
+      if self.dragged_node[1] ~= node then
+        for i, v in ipairs(node.views) do if v.doc == tab.doc then tab = nil break end end
+        if tab then
+          self.dragged_node[1]:remove_view(self.root_node, tab)
+          node:add_view(tab, tab_index)
+          self.root_node:update_layout()
+          self.dragged_node = { node, tab_index or #node.views }
+          core.redraw = true
         end
       else
-    core.request_cursor(node.active_view.cursor)
+        table.remove(self.dragged_node[1].views, self.dragged_node[2])
+        table.insert(node.views, tab_index, tab)
+        self.dragged_node = { node, tab_index }
+      end
   end
 end