Best way to expose an object in winform for editing? - winforms

Question

I have an object from a deserialized XML.
I want to visualize it and make it editable from the UI.
This seemed very easy in the beginning, but it's getting more confusing as I delve deeper into it.
My first approach was using a splitted panel:
- In the left, a TreeView.
- In the right, a ListView showing the value/object selected in the TreeView.
Te problem is that I don't know how to link everything (list and tree) with the object.
I populate the TreeView by going through each element in the object.
Edit: Is it possible to be implemented in CLR. I need to use some C++ code besides this.

Answer 1

So you have a TreeView object that shows TreeNodes, where every TreeNode show one System.Xml.XmlNode. The (sub-)Nodes of each TreeNode correspond with the Children of the XmlNode.
You'll have to decide what Text to display for the XmlNode, but that is a minor problem.
class XmlTreeNode : System.Windows.Forms.TreeNode
{
public XmlTreeNode(System.Xml.XmlNode xmlNode) : base()
{
this.XmlNode = xmlNode;
string textToDisplay = xmlNode.ToDisplayText();
this.Text = textToDisplay;
foreach (var childXmlNode in xmlNode.xmlNodeList.Cast<XmlNode>())
{
XmlTreeNode childNode = new XmlTreeNode(childXmlNode);
this.Nodes.Add(childNode);
}
}
public XmlNode XmlNode {get; private set;}
}
Of course an XmlNode does not have a method ToDisplayText(), so let's create an extension function for this. See extension methods demystified
static string ToDisplayText(this System.Xml.XmlNode xmlNode)
{
// TODO: what would you like to Display?
return xmlNode.Name;
}
Of course you want to be able to show these XmlTreeNodes in an XmlTreeNodeView:
class XmlTreeNodeView : System.Windows.Forms.TreeView
{
// default constructor: constructs empty XmlTreeNodeView:
public XmlTreeNodeView() : base() {}
// constructor fills the XmlTreeNodeView with the XmlNodes:
public XmlTreeNodeView(IEnumerable<XmlNode> xmlNodes) : base()
{
foreach (XmlNode xmlNode in xmlNodes)
{
this.Nodes.Add(new XmlTreeNode(xmlNode));
}
}
And of course you want to be notified if one of the nodes is clicked
public class XmlTreeNodeEventArgs : EventArgs
{
public XmlNode XmlNode {get; set;}
}
And in your XmlTreeView class:
public event EventHandler<XmlTreeNodeEventArgs> XmlNodeClicked;
protected virtual void OnXmlNodeClicked(XmlNode node)
{
return XmlNodeClicked?.Invoke(new XmlTreeNodeEventArgs() {XmlNode = node});
}
protected override void OnAfterSelect (System.Windows.Forms.TreeViewEventArgs e)
{
// get the XmlTreeNode that was clicked:
XmlTreeNode node = (XmlTreeNode)e.Node;
this.OnXmlNodeClicked(node);
}
The nice thing is, that you have to do pretty stupid things to get other things than XmlNodes in your XmlTreeView.
If you really want to prevent that something different than an XmlNode is added, your XmlTreeView should not inherit from TreeView, but from UserControl. The UserControl should show a TreeView inside it. Although this method works, you'll have to copy all TreeView functionality that you want to expose. I'm not sure if the extra work weighs up to the cost of extra security that your XmlTreeView contains only XmlTreeNodes.