Resolve "Merge the best from 7.40 branch"

SabrehavenOTClient/modules/corelib/ui/uitextedit.lua

@@ -0,0 +1,78 @@
+function UITextEdit: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)
+    end
+  end
+end
+
+function UITextEdit:onMouseWheel(mousePos, mouseWheel)
+  if self.verticalScrollBar and self:isMultiline() then
+    if mouseWheel == MouseWheelUp then
+      self.verticalScrollBar:decrement()
+    else
+      self.verticalScrollBar:increment()
+    end
+    return true
+  elseif self.horizontalScrollBar then
+    if mouseWheel == MouseWheelUp then
+      self.horizontalScrollBar:increment()
+    else
+      self.horizontalScrollBar:decrement()
+    end
+    return true
+  end
+end
+
+function UITextEdit:onTextAreaUpdate(virtualOffset, virtualSize, totalSize)
+  self:updateScrollBars()
+end
+
+function UITextEdit:setVerticalScrollBar(scrollbar)
+  self.verticalScrollBar = scrollbar
+  self.verticalScrollBar.onValueChange = function(scrollbar, value)
+    local virtualOffset = self:getTextVirtualOffset()
+    virtualOffset.y = value
+    self:setTextVirtualOffset(virtualOffset)
+  end
+  self:updateScrollBars()
+end
+
+function UITextEdit:setHorizontalScrollBar(scrollbar)
+  self.horizontalScrollBar = scrollbar
+  self.horizontalScrollBar.onValueChange = function(scrollbar, value)
+    local virtualOffset = self:getTextVirtualOffset()
+    virtualOffset.x = value
+    self:setTextVirtualOffset(virtualOffset)
+  end
+  self:updateScrollBars()
+end
+
+function UITextEdit:updateScrollBars()
+  local scrollSize = self:getTextTotalSize()
+  local scrollWidth = math.max(scrollSize.width - self:getTextVirtualSize().width, 0)
+  local scrollHeight = math.max(scrollSize.height - self:getTextVirtualSize().height, 0)
+
+  local scrollbar = self.verticalScrollBar
+  if scrollbar then
+    scrollbar:setMinimum(0)
+    scrollbar:setMaximum(scrollHeight)
+    scrollbar:setValue(self:getTextVirtualOffset().y)
+  end
+
+  local scrollbar = self.horizontalScrollBar
+  if scrollbar then
+    scrollbar:setMinimum(0)
+    scrollbar:setMaximum(scrollWidth)
+    scrollbar:setValue(self:getTextVirtualOffset().x)
+  end
+
+end
+
+-- todo: ontext change, focus to cursor