From 912ae93d1036b78578c2568e98bf691720193818 Mon Sep 17 00:00:00 2001
From: Bill Ferguson <wpferguson@gmail.com>
Date: Sun, 9 Aug 2020 01:56:48 -0400
Subject: [PATCH] Added check to ensure we are in lighttable view prior to
 callling darktable.register_lib.  If darktable was invoked in single image
 (darkroom) mode, then an event handler is registered to detect the change
 from darkroom mode to lighttable mode so that we can then call
 darktable.register_lib.

---
 tools/executable_manager.lua | 57 ++++++++++++++++++++++++------------
 1 file changed, 39 insertions(+), 18 deletions(-)

diff --git a/tools/executable_manager.lua b/tools/executable_manager.lua
index f45ecb6..2bbe392 100644
--- a/tools/executable_manager.lua
+++ b/tools/executable_manager.lua
@@ -40,6 +40,10 @@ local gettext = dt.gettext
 
 gettext.bindtextdomain("executable_manager",dt.configuration.config_dir.."/lua/locale/")
 
+local exec_man = {} -- our own namespace
+exec_man.module_installed = false
+exec_man.event_registered = false
+
 -- - - - - - - - - - - - - - - - - - - - - - - - - - - - 
 -- F U N C T I O N S
 -- - - - - - - - - - - - - - - - - - - - - - - - - - - - 
@@ -86,12 +90,30 @@ local function update_combobox_choices(combobox, choice_table, selected)
   combobox.value = selected
 end
 
+local function install_module()
+  if not exec_man.module_installed then
+    dt.register_lib(
+      "executable_manager",     -- Module name
+      "executable manager",     -- Visible name
+      true,                -- expandable
+      false,               -- resetable
+      {[dt.gui.views.lighttable] = {"DT_UI_CONTAINER_PANEL_LEFT_BOTTOM", 100}},   -- containers
+      dt.new_widget("box") -- widget
+      {
+        orientation = "vertical",
+        exec_man.selector,
+        exec_man.stack,
+      },
+      nil,-- view_enter
+      nil -- view_leave
+    )
+    exec_man.module_installed = true
+  end
+end
 -- - - - - - - - - - - - - - - - - - - - - - - - - - - - 
 -- M A I N   P R O G R A M
 -- - - - - - - - - - - - - - - - - - - - - - - - - - - - 
 
-local exec_man = {} -- our own namespace
-
 local DARKTABLERC = dt.configuration.config_dir .. PS .. "darktablerc"
 
 
@@ -187,19 +209,18 @@ update_combobox_choices(exec_man.selector, exec_table, 1)
 -- register the lib
 
 
-dt.register_lib(
-  "executable_manager",     -- Module name
-  "executable manager",     -- Visible name
-  true,                -- expandable
-  false,               -- resetable
-  {[dt.gui.views.lighttable] = {"DT_UI_CONTAINER_PANEL_LEFT_BOTTOM", 100}},   -- containers
-  dt.new_widget("box") -- widget
-  {
-    orientation = "vertical",
-    exec_man.selector,
-    exec_man.stack,
-  },
-  nil,-- view_enter
-  nil -- view_leave
-)
-
+if dt.gui.current_view().name == "lighttable" then
+  install_module()
+else
+  if not exec_man.event_registered then
+    dt.register_event(
+      "view-changed",
+      function(event, old_view, new_view)
+        if new_view.name == "lighttable" and old_view.name == "darkroom" then
+          install_module()
+         end
+      end
+    )
+    exec_man.event_registered = true
+  end
+end