void SetCustomCss()
{
var mainDocument = Widget.MainFrameDocument ?? Widget.MainFrame.DomDocument;
var head = mainDocument?.DocumentElement?.GetElementsByTagName("head")? [0];
if (head == null)
{
customCssNode = null;
return;
}
// reuse node reference only if the document did not change and still contains the injected node
if (customCssNode != null && !head.ChildNodes.Contains(customCssNode))
{
customCssNode = null;
}
if (!string.IsNullOrEmpty(CustomCss))
{
if (customCssNode == null)
{
customCssNode = mainDocument.CreateElement("style");
customCssNode.SetAttribute("type", "text/css");
if (head.ChildNodes.Count > 0)
{
head.InsertBefore(customCssNode, head.FirstChild);
}
else
{
head.AppendChild(customCssNode);
}
}
if (customCssNode.FirstChild != null)
{
customCssNode.ReplaceChild(mainDocument.CreateTextNode(customCss), customCssNode.FirstChild);
}
else
{
customCssNode.AppendChild(mainDocument.CreateTextNode(customCss));
}
}
else if (customCssNode != null)
{
if (head.ChildNodes.Contains(customCssNode) == true)
{
head.RemoveChild(customCssNode);
}
customCssNode.Dispose();
customCssNode = null;
}
}