Natively support entry icons in the List widget.

library/lua/gui/materials.lua

@@ -46,6 +46,7 @@ function MaterialDialog:init(info)
         widgets.List{
             view_id = 'list',
             frame = { l = 0, r = 0, t = 6, b = 2 },
+            icon_width = 2,
             on_submit = self:callback('onSubmitItem'),
         },
         widgets.EditField{
@@ -83,12 +84,12 @@ end
 
 function MaterialDialog:initBuiltinMode()
     local choices = {
-        { text = '  none', mat_type = -1, mat_index = -1 },
+        { text = 'none', mat_type = -1, mat_index = -1 },
-        { text = ARROW..' inorganic', key = 'CUSTOM_SHIFT_I',
+        { icon = ARROW, text = 'inorganic', key = 'CUSTOM_SHIFT_I',
           cb = self:callback('initInorganicMode') },
-        { text = ARROW..' creature', key = 'CUSTOM_SHIFT_C',
+        { icon = ARROW, text = 'creature', key = 'CUSTOM_SHIFT_C',
           cb = self:callback('initCreatureMode')},
-        { text = ARROW..' plant', key = 'CUSTOM_SHIFT_P',
+        { icon = ARROW, text = 'plant', key = 'CUSTOM_SHIFT_P',
           cb = self:callback('initPlantMode') },
     }
 
@@ -138,8 +139,8 @@ function MaterialDialog:addObjectChoice(choices, obj, name, typ, index)
         self:addMaterial(choices, obj.material[0], typ, index, true)
     else
         table.insert(choices, {
-            text = ARROW..' '..name, mat_type = typ, mat_index = index,
+            icon = ARROW, text = name, mat_type = typ, mat_index = index,
-            ctx = name, obj = obj, cb = self:callback('onSelectObj')
+            obj = obj, cb = self:callback('onSelectObj')
         })
     end
 end
@@ -147,7 +148,7 @@ end
 function MaterialDialog:onSelectObj(item)
     local choices = {}
     self:addMaterials(choices, item.obj.material, item.mat_type, item.mat_index)
-    self:pushContext(item.ctx, choices)
+    self:pushContext(item.text, choices)
 end
 
 function MaterialDialog:addMaterials(choices, vector, tid, index, maxid, field)
@@ -183,7 +184,7 @@ function MaterialDialog:addMaterial(choices, mat, typ, idx, pfix)
         key = mat.prefix
     end
     table.insert(choices, {
-        text = '  '..name,
+        text = name,
         search_key = key,
         material = mat,
         mat_type = typ, mat_index = idx

library/lua/gui/widgets.lua

@@ -222,6 +222,13 @@ function render_text(obj,dc,x0,y0,pen,dpen)
                 end
             end
 
+            if token.tile then
+                x = x + 1
+                if dc then
+                    dc:char(nil, token.tile)
+                end
+            end
+
             if token.text or token.key then
                 local text = getval(token.text) or ''
                 local keypen
@@ -356,6 +363,7 @@ List.ATTRS{
     on_submit = DEFAULT_NIL,
     row_height = 1,
     scroll_keys = STANDARDSCROLL,
+    icon_width = DEFAULT_NIL,
 }
 
 function List:init(info)
@@ -399,7 +407,7 @@ function List:getContentWidth()
         end
         width = math.max(width, roww)
     end
-    return width
+    return width + (self.icon_width or 0)
 end
 
 function List:getContentHeight()
@@ -449,6 +457,7 @@ function List:onRenderBody(dc)
     local choices = self.choices
     local top = self.page_top
     local iend = math.min(#choices, top+self.page_size-1)
+    local iw = self.icon_width
 
     for i = top,iend do
         local obj = choices[i]
@@ -465,7 +474,17 @@ function List:onRenderBody(dc)
         end
 
         local y = (i - top)*self.row_height
-        render_text(obj, dc, 0, y, cur_pen, cur_dpen)
+
+        if iw and obj.icon then
+            dc:seek(0, y)
+            if type(obj.icon) == 'table' then
+                dc:char(nil,obj.icon)
+            else
+                dc:string(obj.icon, obj.icon_pen or cur_pen)
+            end
+        end
+
+        render_text(obj, dc, iw or 0, y, cur_pen, cur_dpen)
 
         if obj.key then
             local keystr = gui.getKeyDisplay(obj.key)