add status widget and attribute

luigi/attribute.lua

@@ -32,7 +32,7 @@ function Attribute.type (widget, value)
 end
 
 --[[--
-widget identifier.
+Widget identifier.
 
 Should contain a unique string identifying the widget, if present.
 
@@ -100,7 +100,7 @@ function Attribute.key (widget, value)
 end
 
 --[[--
-widget value.
+Widget value.
 
 Some widget types expect the value to be of a specific type and
 within a specific range. For example, `slider` and `progress`
@@ -118,7 +118,7 @@ function Attribute.value (widget, value)
 end
 
 --[[--
-widget style.
+Widget style.
 
 Should contain a string or array of strings identifying
 style rules to be applied to the widget. When resolving
@@ -140,6 +140,21 @@ function Attribute.style (widget, value)
     widget.reshape(widget.parent or widget)
 end
 
+--[[--
+Status message.
+
+Should contain a short, single-line string describing the
+purpose or state of the widget.
+
+This string will appear in any `status` type widgets
+in the same layout, or in the master layout if one exists.
+
+@attrib status
+--]]--
+function Attribute.status (widget, value)
+    widget.attributes.status = value
+end
+
 --[[--
 Scroll ability.
 

luigi/input.lua

@@ -227,7 +227,8 @@ function Input:handleWheelMove (layout, x, y)
     local root = layout.root
     local mx, my = Backend.getMousePosition()
     local widget = layout:getWidgetAt(mx, my)
-
+    local hit = true
+    
     if not widget then
         hit = nil
         widget = layout.root

luigi/layout.lua

@@ -255,19 +255,7 @@ function Layout:getWidgetAt (x, y, root)
     if root:isAt(x, y) then return root end
 end
 
--- Internal, called from Widget:new
---[[
-function Layout:addWidget (widget)
-    if widget.id then
-        self[widget.id] = widget
-    end
-    if widget.key then
-        self.accelerators[widget.key] = widget
-    end
-end
-]]
-
--- Add handlers for keyboard accelerators and tab focus
+-- Add handlers for keyboard accelerators, tab focus, and mouse wheel scroll
 function Layout:addDefaultHandlers ()
     self.accelerators = {}
 
@@ -331,6 +319,7 @@ function Layout:addDefaultHandlers ()
     end)
 
     self:onWheelMove(function (event)
+        if not event.hit then return end
         for widget in event.target:eachAncestor(true) do
             if widget.scroll then
                 if not widget.scrollY then
@@ -354,6 +343,14 @@ function Layout:addDefaultHandlers ()
         return false
     end) -- wheel move
 
+    self:onEnter(function (event)
+        local statusWidget = (self.master or self).statusWidget
+        if not statusWidget then return end
+
+        statusWidget.text = event.target.status
+        return false
+    end)
+
 end
 
 Event.injectBinders(Layout)

luigi/widget.lua

@@ -26,6 +26,7 @@ Widget.typeDecorators = {
     radio = require(ROOT .. 'widget.radio'),
     sash = require(ROOT .. 'widget.sash'),
     slider = require(ROOT .. 'widget.slider'),
+    status = require(ROOT .. 'widget.status'),
     stepper = require(ROOT .. 'widget.stepper'),
     text = require(ROOT .. 'widget.text'),
 }
@@ -59,7 +60,8 @@ local function metaIndex (self, property)
 
     -- cascading attributes
     -- TODO: custom accessors in attribute module?
-    if property == 'color' or property == 'font' or property == 'size' then
+    if property == 'color' or property == 'font' or property == 'size'
+    or property == 'status' then
         local value = self.parent and self.parent[property]
         if value ~= nil then return maybeCall(value, self) end
     end

luigi/widget/status.lua

@@ -0,0 +1,9 @@
+--[[--
+A status bar.
+
+@widget status
+--]]--
+
+return function (self)
+    self.layout.statusWidget = self
+end