[SOLVED]tshelltreeview how to fully expand the tree

[petevick]

I'm just looking at the TShellTreeView control for possible use in a project. The first thing I've come across is that there doesn't seem to be a property to expand the tree as you would see in Linux Nemo for example. There is an AutoExpand property but that is for when a user clicks on a node.
There must be some way to expand the tree, but even Google has let me down.

[balazsszekely]

I'm just looking at the TShellTreeView control for possible use in a project. The first thing I've come across is that there doesn't seem to be a property to expand the tree as you would see in Linux Nemo for example. There is an AutoExpand property but that is for when a user clicks on a node.
There must be some way to expand the tree, but even Google has let me down.

Did you try FullExpand/FullCollapse?

[petevick]

Did you try FullExpand/FullCollapse?

I've just tried FullExpand but I'm obviously not using it correctly as the program hangs. added it in both the form Activate and Create procedures, hangs in both, no compile errors.

[balazsszekely]

Did you try FullExpand/FullCollapse?

I've just tried FullExpand but I'm obviously not using it correctly as the program hangs. added it in both the form Activate and Create procedures, hangs in both, no compile errors.

If the tree structure is big, full expand will take time. If you wish to expand only level x nodes, you can try something like this:

Code: Pascal  [Select][+][-]

1. var
2.   I: Integer;
3.   Len: Integer;
4.   NodeToExpand: array of TTreeNode;
5. begin
6.   NodeToExpand := nil;
7.   for I := 0 to ShellTreeView1.Items.Count - 1 do
8.   begin
9.     if ShellTreeView1.Items.Item[I].Level = 1 then
10.     begin
11.       Len := Length(NodeToExpand);
12.       SetLength(NodeToExpand, Len + 1);
13.       NodeToExpand[Len] := ShellTreeView1.Items.Item[I];
14.     end;
15.   end;
16.   for I := Low(NodeToExpand) to High(NodeToExpand) do
17.     NodeToExpand[I].Expand(False);  
18. end;

In the above example the level is 1, but you can change it according to your needs.

[petevick]

[
If the tree structure is big, full expand will take time. If you wish to expand only level x nodes, you can try something like this:

Code: Pascal  [Select][+][-]

1. var
2.   I: Integer;
3.   Len: Integer;
4.   NodeToExpand: array of TTreeNode;
5. begin
6.   NodeToExpand := nil;
7.   for I := 0 to ShellTreeView1.Items.Count - 1 do
8.   begin
9.     if ShellTreeView1.Items.Item[I].Level = 1 then
10.     begin
11.       Len := Length(NodeToExpand);
12.       SetLength(NodeToExpand, Len + 1);
13.       NodeToExpand[Len] := ShellTreeView1.Items.Item[I];
14.     end;
15.   end;
16.   for I := Low(NodeToExpand) to High(NodeToExpand) do
17.     NodeToExpand[I].Expand(False);  
18. end;

In the above example the level is 1, but you can change it according to your needs.

Thanks for that, it's exactly what I was looking for 

[balazsszekely]

@petevick

Thanks for that, it's exactly what I was looking for 

You are welcome! You can speed up things with beginupdate/endupdate. See attached project form more details.