Merge pull request #188 from chrox/scroll_text

add missing scrollbar widget

frontend/ui/widget/scrollbar.lua

@@ -0,0 +1,34 @@
+
+VerticalScrollBar = Widget:new{
+	enable = true,
+	low = 0,
+	high = 1,
+
+	width = 6,
+	height = 50,
+	bordersize = 1,
+	bordercolor = 15,
+	radius = 0,
+	rectcolor = 15,
+}
+
+function VerticalScrollBar:getSize()
+	return Geom:new{
+		w = self.width,
+		h = self.height
+	}
+end
+
+function VerticalScrollBar:set(low, high)
+	self.low = low > 0 and low or 0
+	self.high = high < 1 and high or 1
+end
+
+function VerticalScrollBar:paintTo(bb, x, y)
+	if not self.enable then return end
+	bb:paintBorder(x, y, self.width, self.height,
+				self.bordersize, self.bordercolor, self.radius)
+	bb:paintRect(x + self.bordersize, y + self.bordersize + self.low*self.height,
+				self.width - 2*self.bordersize,
+				self.height * (self.high - self.low), self.rectcolor)
+end