Iterate over top two levels of Treeview nodes?

Taytoo

Have a Treeview with 3 levels, is there a simple way to iterate in a single loop over the top two levels:

Node 1
-> Node 2
--> Node 3
Node 4
Node 5
-> Node 6
--> Node 7

Need to loop over Nodes: 1, 2, 4, 5, 6

JonB

for node0 in topLevelNodes:
    doSomething(node0)
    for node1 in node0.children:
        doSomething(node1)

Taytoo

@JonB That's what I'm doing currently. Was hoping there was a better way to get nodes of n-levels as a singular list and iterate over them.

kshegunov

@Taytoo said in Iterate over top two levels of Treeview nodes?:

@JonB That's what I'm doing currently. Was hoping there was a better way to get nodes of n-levels as a singular list and iterate over them.

It is possible by using a different representation of the tree. It is not immediately straightforward though. Typically trees can be 'linearized' by keeping a left:right traversal index (the so-called "nested set model").

JonB

@Taytoo said in Iterate over top two levels of Treeview nodes?:

Was hoping there was a better way to get nodes of n-levels as a singular list and iterate over them.

There is, but that is not what you asked for. You wrote:

is there a simple way to iterate in a single loop over the top two levels

My answer would not scale for n-levels. Nor would it be right for "visit every node which is not a leaf". One would probably do either of those recursively. And it would not be a "single loop", which I now notice but did not before, if that is what is vital to you. So you have to state exactly what it is you are looking for.