TreeView Question

[Michael C]

Hi all,

Quick question about the TreeView control. I'm using code like this to
determine the currently clicked TreeNode in the TreeView.

private void MyTreeView_MouseDown(object sender,
System.Windows.Forms.MouseEventArgs e)
{
currentNode = MyTreeView.GetNodeAt(e.X, e.Y);
}

The problem I have is, if you click on whitespace to the right of a
TreeNode, it returns the TreeNode to the left. I would like it to return a
null value if you click on whitespace to the right of the TreeNode; as you
receive a null value if you click on whitespace at the bottom of the
TreeView. Anyone know how I can accomplish this?

Thanks,
Michael C., MCDBA

 

[Morten Wennevik]

Hi Michael,

I suppose you can test if the click is within the left -> left + width of the TreeNode using TreeNode.Bounds.
However, in my test I could only get bounds from the root and the first generation, any deeper generation had no bounds.

 

[Michael C]

Thanks Morten,

I was working along similar lines and I think I came up with something.
Here's what I have:

private void MyTreeView_MouseDown(object sender,
System.Windows.Forms.MouseEventArgs e)
{
// Convert Mouse X, Y coords to a TreeNode
currentNode = MyTreeView.GetNodeAt(e.X, e.Y);
// If currentNode is not null and the mouse point is within the
bounds
// of currentNode, we are clicking directly over the TreeNode
// otherwise, if currentNode is null, or the mouse point is outside
the
// bounds of currentNode, we are not directly over the TreeNode
if (currentNode != null && currentNode.Bounds.Contains(e.X, e.Y))
InNode = true;
else

InNode = false;
}

The only issue I'm having now is a simple display issue. When I right-click
on the whitespace to the right of a TreeNode, I don't want the TreeNode to
be highlighted. I'm not sure how to stop it from being highlighted if it's
not clicked directly on. I'm thinking I have to intercept another event,
but not sure which one. Any ideas?

Thanks,
Michael C., MCDBA

Hi Michael,

I suppose you can test if the click is within the left -> left + width of

the TreeNode using TreeNode.Bounds.

However, in my test I could only get bounds from the root and the first

generation, any deeper generation had no bounds.

 

[Chris R. Timmons]

Hi all,

Quick question about the TreeView control. I'm using code like
this to determine the currently clicked TreeNode in the
TreeView.

private void MyTreeView_MouseDown(object sender,
System.Windows.Forms.MouseEventArgs e)
{
currentNode = MyTreeView.GetNodeAt(e.X, e.Y);
}

The problem I have is, if you click on whitespace to the right
of a TreeNode, it returns the TreeNode to the left. I would
like it to return a null value if you click on whitespace to the
right of the TreeNode; as you receive a null value if you click
on whitespace at the bottom of the TreeView. Anyone know how I
can accomplish this?

Michael,

..Net doesn't expose all of the native TreeView capability. There's a
way to send a HIT_TEST_INFO message to a TreeView and find out
exactly where the mouse click occurred. I have a small C# library of
utility routines on my web site at:

http://www.crtimmonsinc.com/Frontend/Desktop/DesktopDefault.aspx?tabi
d=1017

or

http://tinyurl.com/4evd6

It includes a subclass of System.Windows.Forms.TreeView that exposes
a GetHitTestInfoAt method, plus an example program showing how it's
used.