max_width in buttontable - prevent overlong text (#3145)

* max_width in buttontable - prevent overlong text

* fix max_width

frontend/ui/widget/buttontable.lua

@@ -1,12 +1,12 @@
+local Blitbuffer = require("ffi/blitbuffer")
+local Button = require("ui/widget/button")
+local Device = require("device")
+local FocusManager = require("ui/widget/focusmanager")
 local HorizontalGroup = require("ui/widget/horizontalgroup")
+local LineWidget = require("ui/widget/linewidget")
 local VerticalGroup = require("ui/widget/verticalgroup")
 local VerticalSpan = require("ui/widget/verticalspan")
-local FocusManager = require("ui/widget/focusmanager")
-local LineWidget = require("ui/widget/linewidget")
-local Blitbuffer = require("ffi/blitbuffer")
-local Button = require("ui/widget/button")
 local Geom = require("ui/geometry")
-local Device = require("device")
 local Screen = Device.screen
 
 local ButtonTable = FocusManager:new{
@@ -46,6 +46,7 @@ function ButtonTable:init()
                 enabled = btn_entry.enabled,
                 callback = btn_entry.callback,
                 width = (self.width - sizer_space)/column_cnt,
+                max_width = (self.width - sizer_space)/column_cnt - 2*self.sep_width - 2*self.padding,
                 bordersize = 0,
                 margin = 0,
                 padding = 0,