TAdvTreeView FindNodeByTextAndColumn return NULL

VCL TMS VCL UI Pack
1

Hi, i'm trying to Find a Node on my Tree using FindNodeByTextAndColumn but couldn't find any node.
My C++ code:

TAdvTreeViewNode *pn,*pn2;
pn = Tree->AddNode();
pn->Text[0] = "Something";
pn2 = Tree->FindNodeByTextAndColumn("Something", 0, true, true);

pn2 is always NULL. Any suggestions?

Thanks

2

When are you executing this code? Can you try wrapping the code with Tree->BeginUpdate(); Tree->EndUpdate(); and then afterwards call Tree->FindNodeByTextAndColumn?

3

Good morning,
the code was already wrapped between Tree->BeginUpdate() and Tree->EndUpdate(), sorry for didn't mention it, so after your answer i tried to do the opposite: i removed those instructions and now works fine. I don't know if this is intended but thank you for the hint.

4

Hmm that's strange, EndUpdate triggers node structure recalculation so it should then allow the method to return the value correctly. But the code needs to be like:

TAdvTreeViewNode *pn,*pn2;
Tree->BeginUpdate();
pn = Tree->AddNode();
pn->Text[0] = "Something";
Tree->EndUpdate();
pn2 = Tree->FindNodeByTextAndColumn("Something", 0, true, true);
5

Modified the code as you suggested. Works well. So the error was that FindNodeByTextAndColumn was inside BeginUpdate() - EndUpdate(), and if i have understood correctly at that time the node structure didn't existed before EndUpdate().

6

That's correct. When adding nodes, the node structure gets updated. If you don't use BeginUpdate & EndUpdate, then that's fine, but it will affect loading performance when you are adding more and more nodes. Therefore, we bundle all node updates into a single call. Of course, only after EndUpdate is called, the node structure is complete and you can start a search.