diff --git a/lib/wibox/layout/align.lua b/lib/wibox/layout/align.lua
index 069f4674..258acb89 100644
--- a/lib/wibox/layout/align.lua
+++ b/lib/wibox/layout/align.lua
@@ -175,11 +175,9 @@ end
 -- This layout only accept three children, all others will be ignored
 -- @tparam table children A table composed of valid widgets
 function align:set_children(children)
-    if not children then return self:reset() end
-    self.first  = children[1]
-    self.second = children[2]
-    self.third  = children[3]
-    self:emit_signal("widget::layout_changed")
+    self:set_first(children[1])
+    self:set_second(children[2])
+    self:set_third(children[3])
 end
 
 --- Fit the align layout into the given space. The align layout will
diff --git a/lib/wibox/layout/constraint.lua b/lib/wibox/layout/constraint.lua
index 99177c1b..e355e5e4 100644
--- a/lib/wibox/layout/constraint.lua
+++ b/lib/wibox/layout/constraint.lua
@@ -54,8 +54,7 @@ end
 -- This layout only accept one children, all others will be ignored
 -- @tparam table children A table composed of valid widgets
 function constraint:set_children(children)
-    self.widget = children and children[1]
-    self:emit_signal("widget::layout_changed")
+    self:set_widget(children[1])
 end
 
 --- Set the strategy to use for the constraining. Valid values are 'max',
diff --git a/lib/wibox/layout/fixed.lua b/lib/wibox/layout/fixed.lua
index f2de84b8..ecc704dc 100644
--- a/lib/wibox/layout/fixed.lua
+++ b/lib/wibox/layout/fixed.lua
@@ -5,6 +5,7 @@
 -- @classmod wibox.layout.fixed
 ---------------------------------------------------------------------------
 
+local unpack = unpack or table.unpack -- luacheck: globals unpack (compatibility with Lua 5.1)
 local base  = require("wibox.widget.base")
 local table = table
 local pairs = pairs
@@ -110,9 +111,10 @@ end
 --- Replace the layout children
 -- @tparam table children A table composed of valid widgets
 function fixed:set_children(children)
-    if not children then return self:reset() end
-    self.widgets = children
-    self:emit_signal("widget::layout_changed")
+    self:reset()
+    if #children > 0 then
+        self:add(unpack(children))
+    end
 end
 
 --- Replace the first instance of `widget` in the layout with `widget2`
diff --git a/lib/wibox/layout/margin.lua b/lib/wibox/layout/margin.lua
index e7629a10..9a8a8b2c 100644
--- a/lib/wibox/layout/margin.lua
+++ b/lib/wibox/layout/margin.lua
@@ -82,8 +82,7 @@ end
 -- This layout only accept one children, all others will be ignored
 -- @tparam table children A table composed of valid widgets
 function margin:set_children(children)
-    self.widget = children and children[1]
-    self:emit_signal("widget::layout_changed")
+    self:set_widget(children[1])
 end
 
 --- Set all the margins to val.
diff --git a/lib/wibox/layout/mirror.lua b/lib/wibox/layout/mirror.lua
index 616bb153..9559d340 100644
--- a/lib/wibox/layout/mirror.lua
+++ b/lib/wibox/layout/mirror.lua
@@ -68,8 +68,7 @@ end
 -- This layout only accept one children, all others will be ignored
 -- @tparam table children A table composed of valid widgets
 function mirror:set_children(children)
-    self.widget = children and children[1]
-    self:emit_signal("widget::layout_changed")
+    self:set_widget(children[1])
 end
 
 --- Reset this layout. The widget will be removed and the axes reset.
diff --git a/lib/wibox/layout/rotate.lua b/lib/wibox/layout/rotate.lua
index 8de9ef7b..46e60b8e 100644
--- a/lib/wibox/layout/rotate.lua
+++ b/lib/wibox/layout/rotate.lua
@@ -76,8 +76,7 @@ end
 -- This layout only accept one children, all others will be ignored
 -- @tparam table children A table composed of valid widgets
 function rotate:set_children(children)
-    self.widget = children and children[1]
-    self:emit_signal("widget::layout_changed")
+    self:set_widget(children[1])
 end
 
 --- Reset this layout. The widget will be removed and the rotation reset.
diff --git a/lib/wibox/layout/scroll.lua b/lib/wibox/layout/scroll.lua
index 1af8f94e..850fee4b 100644
--- a/lib/wibox/layout/scroll.lua
+++ b/lib/wibox/layout/scroll.lua
@@ -267,8 +267,7 @@ end
 -- This layout only accept one children, all others will be ignored
 -- @tparam table children A table composed of valid widgets
 function scroll:set_children(children)
-    self.widget = children and children[1]
-    self:emit_signal("widget::layout_changed")
+    self:set_widget(children[1])
 end
 
 --- Specify the expand mode that is used for extra space.
diff --git a/lib/wibox/widget/background.lua b/lib/wibox/widget/background.lua
index 274d8024..7d547124 100644
--- a/lib/wibox/widget/background.lua
+++ b/lib/wibox/widget/background.lua
@@ -109,8 +109,7 @@ end
 -- This layout only accept one children, all others will be ignored
 -- @tparam table children A table composed of valid widgets
 function background:set_children(children)
-    self.widget = children and children[1]
-    self:emit_signal("widget::layout_changed")
+    self:set_widget(children[1])
 end
 
 --- Set the background to use