c# winform : node expand and collapse in TreeView - c#

Is method that do it to be extended by icon in front of node without clicking node only?

If you can get a reference to a TreeNode object, you can call the following methods:
treeNode.Expand()
treeNode.Collapse()
These will expand and collapse any given node, assuming you want to do so programmatically rather than requiring the user to click the node.

Related

How to make child node of a treeview control to make panel control visible

how to write a click event for a child node of a tree view control...
if i click the child node a static panel should be visible.
As far as I know , the only way is to programatically tell which node is selected (retrieve the appropriate node via the e.Node parameter), then fire the corresponding functionality.
This code can be placed within TreeView.AfterSelect event.

Refresh a treeview and expand last selected node

In my application i copy a certain pdf file to the selected node, after this i want the treeview to refresh and show me the added file.
The refresh is working but it won't expand the last selected node.
How can i do a refresh but still keep the last selected node expanded, so the user can see that the pdf file is added to the folder.
The AfterSelect on the TreeView have a parameter TreeViewEventArgs e. e.Node will return the selected node. eg:
e.Node.Expand();
or
e.Node.ExpandAll();
Should you wish to expand all the nodes in the treeview. You can use the same method to expand the
I assume that you know which node you have copied it too. Use the same method to expand the node you've copied too.

Empty expandable treenode in C#

I want to create an expandable empty treenode in C#, i.e. a treenode which is empty and has the [+] sign beside it. The reason is because initially it is empty, but once a node is clicked, I want to populate it with many child nodes.
The only problem I am facing is that empty treenodes aren't expandable, so I don't know what to do. Is there a way to solve this problem, or are there any workarounds?
You have to redraw the tree itself, or create an empty node and simply remove it when the parent node is expanded.
Personally, I'd go for option b). I've done this before, a while ago and thanks to the events raised by the TreeView it pretty easy to accomplish.
You can give the empty node a value like 'Loading...' so it gives some feedback to the user as well. :)
Add a dummy child node, and remove it when you expand.
Have a look at Josh Smiths excellent tutorial on treeviews. It allows lazy loading of child tree nodes by having a dummy node that is removed upon expansion.

select a node in treeview programmatically in windows application

i have load a tree view. i want to Traverse treeview node and expand & select a node. Expand is working fine. but select a node is not working.
private void Traverse(TreeNodeCollection nodes, string findtext)
{
foreach (TreeNode node in nodes)
{
if (node.Text.ToString().Trim() == findtext)
{
node.Expand();
node.TreeView.SelectedNode = node.NextNode;
//tvwStructureTree.SelectedNode = this.tvwStructureTree.Nodes[node.Index];
//Select a node in Treeview tvwStructureTree But not working
tvwStructureTree.SelectedNode = node;
node.TreeView.Focus();
}
Traverse(node.Nodes, findtext);
}
}
Its in windows application.
Not quite sure what's your issue is. TreeView.SelectedNode Property is the correct property.
When you set this property, the specified node is scrolled into view
and any parent nodes are expanded so that the specified node is
visible.
When the parent node or any ancestor node of the selected node is
collapsed either programmatically or through user action, the
collapsed node becomes the selected node.
Make sure that the node.TreeView is the correct TreeView instance.
node.TreeView.SelectedNode = node.NextNode;
TreeView.HideSelection Property is another property that might useful for you.
When this property is set to false, selected nodes in the TreeView
control remain highlighted in a different color than the current
selection color when the TreeView control loses focus. You can use
this property to keep items that are selected by the user visible when
the user clicks a different control on the form or moves to a
different window.
I had a similar issue. My form's ctor is given the test of a node to select.Finding the correct node was not a problem, but the tree didn't show the node as selected, since the tree control didn't have focus. merely had to use Form.ActiveControl = myTreecontrol; before setting myTreecontrol.SelectedNode
I tested exactly your own code and worked fine, both find and selection the node!
without any particular property setting for my treeview!
by the way I am using .Net 3.5 and VS 2008

Select or Click event for a TreeView Child node

I have a treeview control in asp.net. It has multiple parents nodes and under each parent node, there are multiple child nodes. When I select a parent node (click on it) a TreeView event called TreeView1_SelectedNodeChanged is triggered. I can write custom code based on requirements. What I am looking for is "On Select" or "On Click" for a Child node. I do not see any events for a child tree node. How do I do this? Although I can write code for Parent node click, I dont see anything for child node click or select.
When you add the child node you can set the SelectAction:
child.SelectAction = TreeNodeSelectAction.Select
That should do it.

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