Merge pull request #198 from chrox/page_button

add page up/down buttons in menus that have more than one pages

frontend/ui/widget/button.lua

@@ -1,10 +1,12 @@
+require "ui/widget/image"
 require "ui/widget/container"
 
 --[[
-a button widget
+a button widget that shows text or a icon and handles callback when tapped
 --]]
 Button = InputContainer:new{
 	text = nil, -- mandatory
+	icon = nil,
 	preselect = false,
 	callback = nil,
 	enabled = true,
@@ -19,15 +21,22 @@ Button = InputContainer:new{
 }
 
 function Button:init()
-	self.text_widget = TextWidget:new{
-		text = self.text,
-		bgcolor = 0.0,
-		fgcolor = self.enabled and 1.0 or 0.5,
-		face = Font:getFace(self.text_font_face, self.text_font_size)
-	}
-	local text_size = self.text_widget:getSize()
+	if self.text then
+		self.label_widget = TextWidget:new{
+			text = self.text,
+			bgcolor = 0.0,
+			fgcolor = self.enabled and 1.0 or 0.5,
+			face = Font:getFace(self.text_font_face, self.text_font_size)
+		}
+	else
+		self.label_widget = ImageWidget:new{
+			file = self.icon,
+			dim = self.enabled,
+		}
+	end
+	local widget_size = self.label_widget:getSize()
 	if self.width == nil then
-		self.width = text_size.w
+		self.width = widget_size.w
 	end
 	-- set FrameContainer content
 	self[1] = FrameContainer:new{
@@ -39,9 +48,9 @@ function Button:init()
 		CenterContainer:new{
 			dimen = Geom:new{
 				w = self.width,
-				h = text_size.h
+				h = widget_size.h
 			},
-			self.text_widget,
+			self.label_widget,
 		}
 	}
 	if self.preselect then
@@ -75,12 +84,48 @@ end
 
 function Button:enable()
 	self.enabled = true
-	self.text_widget.fgcolor = 1.0
+	if self.text then
+		self.label_widget.fgcolor = self.enabled and 1.0 or 0.5
+	else
+		self.label_widget.dim = not self.enabled
+	end
 end
 
 function Button:disable()
 	self.enabled = false
-	self.text_widget.fgcolor = 0.5
+	if self.text then
+		self.label_widget.fgcolor = self.enabled and 1.0 or 0.5
+	else
+		self.label_widget.dim = not self.enabled
+	end
+end
+
+function Button:enableDisable(enable)
+	if enable then
+		self:enable()
+	else
+		self:disable()
+	end
+end
+
+function Button:hide()
+	if self.icon then
+		self.label_widget.hide = true
+	end
+end
+
+function Button:show()
+	if self.icon then
+		self.label_widget.hide = false
+	end
+end
+
+function Button:showHide(show)
+	if show then
+		self:show()
+	else
+		self:hide()
+	end
 end
 
 function Button:onTapSelect()

frontend/ui/widget/image.lua

@@ -6,8 +6,10 @@ require "ui/image"
 ImageWidget shows an image from a file
 --]]
 ImageWidget = Widget:new{
-	invert = nil,
 	file = nil,
+	invert = nil,
+	dim = nil,
+	hide = nil,
 	_bb = nil
 }
 
@@ -34,10 +36,14 @@ function ImageWidget:paintTo(bb, x, y)
 		w = size.w,
 		h = size.h 
 	}
+	if self.hide then return end
 	bb:blitFrom(self._bb, x, y, 0, 0, size.w, size.h)
 	if self.invert then
 		bb:invertRect(x, y, size.w, size.h)
 	end
+	if self.dim then
+		bb:dimRect(x, y, size.w, size.h)
+	end
 end
 
 function ImageWidget:free()

frontend/ui/widget/menu.lua

@@ -1,6 +1,7 @@
 require "ui/widget/container"
 require "ui/widget/focusmanager"
 require "ui/widget/infomessage"
+require "ui/widget/button"
 require "ui/widget/text"
 require "ui/widget/group"
 require "ui/widget/span"
@@ -287,8 +288,27 @@ function Menu:init()
 	end
 	-- group for items
 	self.item_group = VerticalGroup:new{}
-		self.page_info = TextWidget:new{
-			face = self.fface,
+	-- group for page info
+	self.page_info_left_chev = Button:new{
+		icon = "resources/icons/appbar.chevron.left.png",
+		callback = function() self:onPrevPage() end,
+		bordersize = 0,
+	}
+	self.page_info_right_chev = Button:new{
+		icon = "resources/icons/appbar.chevron.right.png",
+		callback = function() self:onNextPage() end,
+		bordersize = 0,
+	}
+	self.page_info_left_chev:hide()
+	self.page_info_right_chev:hide()
+	self.page_info_text = TextWidget:new{
+		text = "",
+		face = self.fface,
+	}
+	self.page_info = HorizontalGroup:new{
+		self.page_info_left_chev,
+		self.page_info_text,
+		self.page_info_right_chev
 	}
 	-- group for menu layout
 	local content = VerticalGroup:new{
@@ -428,9 +448,13 @@ function Menu:updateItems(select_number)
 			self.item_group[select_number]:onFocus()
 		end
 		-- update page information
-		self.page_info.text = _("page ")..self.page.."/"..self.page_num
+		self.page_info_text.text = _("page ")..self.page.."/"..self.page_num
+		self.page_info_left_chev:showHide(self.page_num > 1)
+		self.page_info_right_chev:showHide(self.page_num > 1)
+		self.page_info_left_chev:enableDisable(self.page > 1)
+		self.page_info_right_chev:enableDisable(self.page < self.page_num)
 	else
-		self.page_info.text = _("no choices available")
+		self.page_info_text.text = _("no choices available")
 	end
 
 	-- FIXME: this is a dirty hack to clear previous menus
@@ -568,5 +592,3 @@ function Menu:onSwipe(arg, ges_ev)
 		self:onPrevPage()
 	end
 end
-
-