Re: [fpc-pascal] TreeView and Nonrecursion

2010-09-02 Thread Bihar Anwar 
On September 2, 2010 5:14:50 PM, Juha Manninen wrote:



> If your input data contains a string which always
> identifies the parent node then you can map the 
> string -> "parent node" and find it later for adding
> a child node.
>
> Pseudo code again:
> ...
> ...
> If you don't have such ID then you must use recursion.

Thanks José and Juha, now I see the light. :-)


On September 2, 2010 8:11:53 PM, Flávio Etrusco wrote:

> When reading from registry and populating a treeview, a
> recursive function is the least of your worries regarding
> "performance" (or memory, if you're careful).

I'm a crash-phobia :-). Stack sizes are different among the OS platforms. A 
superdeep recursion will trigger a stack overflow exception.




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Re: [fpc-pascal] TreeView and Nonrecursion

2010-09-02 Thread Flávio Etrusco 
On Wed, Sep 1, 2010 at 6:20 PM, Bihar Anwar  wrote:
> On 2 September 2010 3:53:34 AM, Vannus wrote:
>
>> i probably shouldn't open my mouth, as i don't quite understand the
>> question...
>> however FRED from the game Freespace let you design missions using a
>> treeview.
>
> Just to make my question clear, for example, I can fill a TreeView control
> with particular Registry keys by enumerating registry keys recursively and
> put them in the TreeView control; then for performance reason, I attempt to
> use a nonrecursive/iterative approach to enumerate registry keys, but how
> can I fill the TreeView since a "tree" is naturally recursive? Is recursion
> is the only way to achive it?
>

When reading from registry and populating a treeview, a recursive
function is the least of your worries regarding "performance" (or
memory, if you're careful).

-Flávio
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Re: [fpc-pascal] TreeView and Nonrecursion

2010-09-02 Thread Juha Manninen (gmail) 
On Thursday 02 September 2010 00:47:23 José Mejuto wrote:
> You must know at which node a new node must be inserted...

If your input data contains a string which always identifies the parent node 
then you can map the string -> "parent node" and find it later for adding a 
child node.

Pseudo code again:

var
  ParentNode, Node: TNode;
  Map: TStringHashMap;
  ParentId, Id: string;
...
  //  get data from somewhere
  ParentId := ...
  Id := ...
  ParentNode := Map[ParentId];
  // This should make Node a root node if ParentNode = nil.
  Node := Tree.AddNode(ParentNode, Id);  // Pseudo syntax.
  Map[Id] := Node;   // Use as parent for following nodes.


If you don't have such ID then you must use recursion.

Juha
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Re[2]: [fpc-pascal] TreeView and Nonrecursion

2010-09-01 Thread José Mejuto 
Hello FPC-Pascal,

Wednesday, September 1, 2010, 11:20:57 PM, you wrote:

BA> Just to make my question clear, for example, I can fill a TreeView control 
with
BA> particular Registry keys by enumerating registry keys recursively and put 
them
BA> in the TreeView control; then for performance reason, I attempt to use a
BA> nonrecursive/iterative approach to enumerate registry keys, but how can I 
fill
BA> the TreeView since a "tree" is naturally recursive? Is recursion is the 
only way
BA> to achive it?

You must know at which node a new node must be inserted, but you can
write something like (pseudo code):

procedure FillConditional(var ParentNode: TNode);
var
  j: integer;
  l: TList;
  n: TNode;
begin
  l:=TList.Create;
  n:=nil;
  for j:=0 to  do begin //xxx is some kind of condition
n:=TNode.Create;
n.position:=j;
Tree.AddNode(ParentNode,n);
if j=10 then begin
  l.add(n); //Remember the node at position 10
end;
  end;
  for j:=0 to n.Count-1 do begin
n:=l.Items[j];
FillConditional(n);
  end;
  l.free;
end;

It is recursive, but first you add all sibliings and them you add each
new brach linearly.

-- 
Best regards,
 José

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Re: [fpc-pascal] TreeView and Nonrecursion

2010-09-01 Thread Bihar Anwar 
On 2 September 2010 3:53:34 AM, Vannus wrote:


> i probably shouldn't open my mouth, as i don't quite understand the  
>question... 
>
> however FRED from the game Freespace let you design missions  using a 
treeview.

Just to make my question clear, for example, I can fill a TreeView control with 
particular Registry keys by enumerating registry keys recursively and put them 
in the TreeView control; then for performance reason, I attempt to use a 
nonrecursive/iterative approach to enumerate registry keys, but how can I fill 
the TreeView since a "tree" is naturally recursive? Is recursion is the only 
way 
to achive it?



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Re: [fpc-pascal] TreeView and Nonrecursion

2010-09-01 Thread Vannus 
i probably shouldn't open my mouth, as i don't quite understand the
question... however FRED from the game Freespace let you design missions
using a treeview.

It involved following a tree like
|- when 'Enemy Cargo ship' is 'attacked'
| \- then 'enemy support ships' do 'jump in'
|- when 'Enemy Cargo ship' is 'destroyed'
| \- then 'mission successful'
|- etc...

or do you mean the other way around where the thinking paradigm fills in the
treeview?

- V

On 1 September 2010 21:40, Bihar Anwar  wrote:

> A Newbie question :-) Is it possible to fill TreeView (tree is naturally
> recursive) with a nonrecursive/iterative thinking paradigm? Are there some
> good
> examples regarding this matter in the Internet?
>
> I post this question in FPC mailing list because my question actually about
> filling a "tree" in general.
>
> Thanks in advance.
>
>
>
>
>
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[fpc-pascal] TreeView and Nonrecursion

2010-09-01 Thread Bihar Anwar 
A Newbie question :-) Is it possible to fill TreeView (tree is naturally 
recursive) with a nonrecursive/iterative thinking paradigm? Are there some good 
examples regarding this matter in the Internet?

I post this question in FPC mailing list because my question actually about 
filling a "tree" in general.

Thanks in advance.



  

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