IntegralUI TreeListView User Guide - Lidor Systems

Selected nodes
Multiple selection
The control supports four different modes for node selection. They are controlled from the
SelectionMode property, which can have following values:
• None – there is no selection
• One – only one node can be selected
• MultiSimple – selection is performed with single mouse click
• MultiExtended – selection is perfomed with use of CTRL or SHIFT keys
In order to have multiple node selection, the SelectionMode must be set either to MultiSimple or
MultiExtended value.
Whenever there is a selection, nodes that are currently selected are stored in SelectedNodes
collection. This collection is very useful when you want to examine only nodes that are currently
selected.
Hover selection
In some cases you may want to allow nodes to be selected while mouse cursor hovers over them.
This functionality is built-in the code, and in order to allow it, just set the HoverSelection
property to True.
How to preserve selection
In some cases you may want to preserve the collection of selected nodes unchanged. For
example, there may be custom operation which will indirectly change the Selected state of the
node, and in this way the SelectedNodes collection. In order to prevent this from happening, we
have added a PreserveSelection property. With it you can preserve the current collection, run
your custom operation without side effects, and then set back this property to its original value.
For example:
[VB]
Private Sub button1_Click(ByVal sender As Object, ByVal e As EventArgs)
Me.treeListView1.PreserveSelection = True
Me.treeListView1.SelectedNodes.Clear()
Me.treeListView1.SelectedNode = Me.treeListView1.Nodes(1)
Me.treeListView1.PreserveSelection = False
End Sub
[C#]
private void button1_Click(object sender, EventArgs e)
{
this.treeListView1.PreserveSelection = true;
this.treeListView1.SelectedNodes.Clear();
this.treeListView1.SelectedNode = this.treeListView1.Nodes[1];
this.treeListView1.PreserveSelection = false;
}
In this example we have a TreeListView with some nodes in it. Whenever a button is clicked the
second node is selected. But along with this by calling the Clear method, we try to remove all
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