tibia-client/modules/core_lib/widgets/uiscrollarea.lua

UIScrollArea = extends(UIWidget)

-- public functions
function UIScrollArea.create()
  local scrollarea = UIScrollArea.internalCreate()
  scrollarea:setClipping(true)
  scrollarea.inverted = false
  return scrollarea
end

function UIScrollArea:onStyleApply(styleName, styleNode)
  for name,value in pairs(styleNode) do
    if name == 'vertical-scrollbar' then
      addEvent(function()
        self:setVerticalScrollBar(self:getParent():getChildById(value))
      end)
    elseif name == 'horizontal-scrollbar' then
      addEvent(function()
        self:setHorizontalScrollBar(self:getParent():getChildById(value))
      end)
    elseif name == 'inverted-scroll' then
      self:setInverted(value)
    end
  end
end

function UIScrollArea:updateScrollBars()
  local offset = { x = 0, y = 0 }
  local scrollheight = math.max(self:getChildrenRect().height - self:getClippingRect().height, 0)
  local scrollwidth = math.max(self:getChildrenRect().width - self:getClippingRect().width, 0)

  local scrollbar = self.verticalScrollBar
  if scrollbar then
    if self.inverted then
      scrollbar:setMinimum(-scrollheight)
      scrollbar:setMaximum(0)
    else
      scrollbar:setMinimum(0)
      scrollbar:setMaximum(scrollheight)
    end
  end

  local scrollbar = self.horizontalScrollBar
  if scrollbar then
    if self.inverted then
      scrollbar:setMinimum(-scrollwidth)
    else
      scrollbar:setMaximum(scrollwidth)
    end
  end
end

function UIScrollArea:setVerticalScrollBar(scrollbar)
  self.verticalScrollBar = scrollbar
  self.verticalScrollBar.onValueChange = function(scrollbar, value)
    local virtualOffset = self:getVirtualOffset()
    virtualOffset.y = value
    self:setVirtualOffset(virtualOffset)
  end
  self:updateScrollBars()
end

function UIScrollArea:setHorizontalScrollBar(scrollbar)
  self.horizontalScrollBar = scrollbar
  self:updateScrollBars()
end

function UIScrollArea:setInverted(inverted)
  self.inverted = inverted
end

function UIScrollArea:onLayoutUpdate()
  self:updateScrollBars()
end

function UIScrollArea:onMouseWheel(mousePos, mouseWheel)
  if self.verticalScrollBar then
    if mouseWheel == MouseWheelUp then
      self.verticalScrollBar:decrement()
    else
      self.verticalScrollBar:increment()
    end
  end
  return true
end