asked on

Delphi, TreeView

Hi i have one function for finding root and formshow procedure
i need much simpler Syntax

Dat.q(q)(q) is TadoDataset

function FindRootNode(ACaption: String; ATreeView: TTreeView): TTreeNode;
var LCount: Integer;
begin
result := nil;
LCount := 0;
while (LCount < ATreeView.Items.Count) and (result = nil) do
begin // and (ATreeView.Items.Item[LCount].Parent = nil)
if (ATreeView.Items.Item[LCount].Text = ACaption) then
begin
result := ATreeView.Items.Item[LCount];
end;
inc(LCount);
end;
end;

procedure TDomainObjectsOperatorLocations.FormShow(Sender: TObject);
var i,j:Integer;
LDestNode, ObjectNode, OperatorNode, LocationNode, DeviceNode: TTreeNode;
begin
inherited;
Dat.q.Close;
Dat.q.CommandText:= ' Select * from domains';
Dat.q.Open;
TreeView1.Items.Clear;
Dat.q.First;
i:=0;
while not Dat.q.Eof do
begin // +' '+Dat.q.FieldByName('NAME').AsString
TreeView1.Items.Add(nil,Dat.q.FieldByName('CODE').AsString); // +' '+Dat.q.FieldByName('NAME').AsString
LDestNode:= FindRootNode(Dat.q.FieldByName('CODE').AsString, TreeView1);
Dat.qq.Close;
Dat.qq.CommandText:= 'Select objects.code, objects.name, objects.domaincode, domains.name as domainname';
Dat.qq.CommandText:= Dat.qq.CommandText + ' from objects left join domains on objects.domaincode=domains.code';
Dat.qq.CommandText:= Dat.qq.CommandText + ' where objects.domaincode='+QuotedStr(Dat.q.FieldByName('CODE').AsString);
Dat.qq.Open;
//objects
if Dat.qq.RecordCount > 0 then
begin
TreeView1.Items.AddChild(LDestNode, 'Objects');
Dat.qq.First;
i:=0;
while not Dat.qq.eof do
begin
ObjectNode:=FindRootNode('Objects', TreeView1); // +' '+Dat.qq.FieldByName('NAME').AsString
TreeView1.Items.AddChild(ObjectNode, Dat.qq.FieldByName('CODE').AsString);
//locations
Dat.qqq.Close;
Dat.qqq.CommandText:= 'Select * from vlocations where objectCode='+QuotedStr(Dat.qq.FieldByName('CODE').AsString);
Dat.qqq.Open;
if Dat.qqq.RecordCount > 0 then
begin // +' '+Dat.qq.FieldByName('NAME').AsString
ObjectNode:= FindRootNode(Dat.qq.FieldByName('CODE').AsString, TreeView1);
TreeView1.Items.AddChild(ObjectNode, 'Locations');
j:=0;
while not Dat.qqq.eof do
begin
LocationNode:= FindRootNode('Locations', TreeView1); // +' '+Dat.qqq.FieldByName('NAME').AsString
TreeView1.Items.AddChild(LocationNode, Dat.qqq.FieldByName('CODE').AsString);
j:=j+1;
if j>3 then
Break;
Dat.qqq.Next;
end;
end;

//devices
Dat.qqq.Close;
Dat.qqq.CommandText:= 'Select * from vDevices where objectCode='+QuotedStr(Dat.qq.FieldByName('CODE').AsString);
Dat.qqq.Open;
if Dat.qqq.RecordCount > 0 then
begin // +' '+Dat.qq.FieldByName('NAME').AsString
DeviceNode:= FindRootNode(Dat.qq.FieldByName('CODE').AsString, TreeView1);
TreeView1.Items.AddChild(DeviceNode, 'Devices');
j:=0;
while not Dat.qqq.eof do
begin
LocationNode:= FindRootNode('Devices', TreeView1);
TreeView1.Items.AddChild(LocationNode, Dat.qqq.FieldByName('CODE').AsString);
j:=j+1;
if j>3 then
Break;
Dat.qqq.Next;
end;
end;

i:=i+1;
if i > 3 then
Break;
Dat.qq.Next;
end;
end;
//operators
Dat.qq.Close;
Dat.qq.CommandText:= 'Select * from vOperators where DomainCOde ='+QuotedStr(Dat.q.FieldByName('CODE').AsString);
Dat.qq.Open;
if Dat.qq.RecordCount > 0 then
begin
TreeView1.Items.AddChild(LDestNode, 'Operators');
Dat.qq.First;
i:=0;
while not Dat.qq.eof do
begin
OperatorNode:=FindRootNode('Operators', TreeView1); // +' '+Dat.qq.FieldByName('NAME').AsString
TreeView1.Items.AddChild(OperatorNode, Dat.qq.FieldByName('CODE').AsString);
i:=i+1;
if i > 3 then
Break;
Dat.qq.Next;
end;
end;
Dat.Q.Next;
end;
end;

Thx, I need simpler solution for this

Geert G

wouldn't it to be easier to let the database do all the work ?
if you have 1 query with the level, the parent id, the caption and optional info

it's just a straight forward running through the query and adding nodes or child nodes
this is a sample with an oracle table

create table test (id number, parent_id number, caption varchar2(200), info varchar2(200));

insert into test (id, parent_id, caption, info) values (1, null, 'Node 1', '');
insert into test (id, parent_id, caption, info) values (2, null, 'Node 2', '');
insert into test (id, parent_id, caption, info) values (3, null, 'Node 3', '');
insert into test (id, parent_id, caption, info) values (4, null, 'Node 4', '');
insert into test (id, parent_id, caption, info) values (5, null, 'Node 5', '');
insert into test (id, parent_id, caption, info) values (6, 1, 'Node 1.1', '');
insert into test (id, parent_id, caption, info) values (7, 1, 'Node 1.2', '');
insert into test (id, parent_id, caption, info) values (8, 2, 'Node 2.1', '');
insert into test (id, parent_id, caption, info) values (9, 4, 'Node 4.1', '');
insert into test (id, parent_id, caption, info) values (10, 5, 'Node 5.1', '');
insert into test (id, parent_id, caption, info) values (11, 8, 'Node 2.1.1', '');
insert into test (id, parent_id, caption, info) values (12, 8, 'Node 2.1.2', '');
insert into test (id, parent_id, caption, info) values (13, 11, 'Node 2.1.1.1', '');
insert into test (id, parent_id, caption, info) values (14, 9, 'Node 4.1.1', '');
insert into test (id, parent_id, caption, info) values (15, 9, 'Node 4.1.2', '');
insert into test (id, parent_id, caption, info) values (16, 10, 'Node 5.1.1', '');
insert into test (id, parent_id, caption, info) values (17, 10, 'Node 5.1.2', '');
insert into test (id, parent_id, caption, info) values (18, 16, 'Node 5.1.1.1', '');
 

select level, id, parent_id, caption, info
from test
start with parent_id is null
connect by prior id = parent_id

Open in new window

the output looks like this, oracle database sorts this automatically

LEVEL,ID,PARENT_ID,CAPTION,INFO
1,1,,Node 1,
2,6,1,Node 1.1,
2,7,1,Node 1.2,
1,2,,Node 2,
2,8,2,Node 2.1,
3,11,8,Node 2.1.1,
4,13,11,Node 2.1.1.1,
3,12,8,Node 2.1.2,
1,3,,Node 3,
1,4,,Node 4,
2,9,4,Node 4.1,
3,14,9,Node 4.1.1,
3,15,9,Node 4.1.2,
1,5,,Node 5,
2,10,5,Node 5.1,
3,16,10,Node 5.1.1,
4,18,16,Node 5.1.1.1,
3,17,10,Node 5.1.2,

Open in new window

why not use a stack to push/pop parentnodes while you build the tree ?
i'll build a test with a tree view

SOLUTION

Geert G

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hrvica5

ASKER

some exception pop upped

Thx
exception.jpg

Geert G

is your data sorted correctly ?

hrvica5

ASKER

I used yours, for example
exc.jpg

Geert G

that data isn't sorted correctly
i guess you're not using oracle ?

no point in using my sample with a stack if the data isn't sorted

hrvica5

ASKER

i'm using mssql.

i'll try to sort correctly.

thx

Geert G

always best to add mssql when you need a query made for that environment

i don't have an mssql at my fingertips for testing

hrvica5

ASKER

Hi i sorted,

Thank you very much you helped me like always.
but for my needs i need to make some procedure / view and sort that way my tables

Thx, Hrvica
sort.jpg

ASKER CERTIFIED SOLUTION

Sinisa Vuk

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hrvica5

ASKER

Sory I tried now with more datas and i get wrong values
I put in attach how my tabel is sorted
and jpeg how it looks in treview

thx
sort.xls
TreeView.jpg

Sinisa Vuk

No need to use parentid anymore. I modified example to use your string parentNode notation. Then oder of sql is going:

select code, node, parentNode form table order by parentNode, node;

procedure FindRootNode(RootNode: TTreeNode; FindIdStr: AnsiString; var node: TTreeNode);
var
  i: Integer;
  sNodeStr: AnsiString;
begin
  if Assigned(RootNode) then
  begin
    sNodeStr := String(PAnsiChar(RootNode.Data));
    if sNodeStr = FindIdStr then
    begin
      node := RootNode;
      Exit;
    end;

    for i := 1 to RootNode.Count do
    begin
      sNodeStr := String(PAnsiChar(RootNode.Item[i-1].Data));
      if sNodeStr = FindIdStr then
      begin
        node := RootNode.Item[i-1];
        Break;
      end
      else
        FindRootNode(RootNode.Item[i-1], FindIdStr, node);

      if Assigned(node) then Break;
    end;
  end;
end;

procedure TForm1.BitBtn1Click(Sender: TObject);
var
  Node, rootNode: TTreeNode;
  parentId, nodeId: AnsiString;
  ptr: PAnsiChar;
begin
  data.First; //sort by parentid, id

  TreeView1.Items.BeginUpdate;
  try
    TreeView1.Items.Clear;

    while not data.Eof do
    begin
      parentId := data.FieldByName('parentNode').AsString;
      nodeId := data.FieldByName('node').AsString;

      rootNode := nil;
      FindRootNode(TreeView1.Items.GetFirstNode, parentId, rootNode);

      ptr := GetMemory(Length(nodeId)+1); //null termnated string
      ZeroMemory(ptr, Length(nodeId)+1);
      StrPCopy(ptr, nodeId);

      if Assigned(rootNode) then
        Node := TreeView1.Items.AddChildObject(rootNode, data.FieldByName('code').AsString, ptr)
      else
        Node := TreeView1.Items.AddObject(rootNode, data.FieldByName('code').AsString, ptr);

      data.Next;
    end;
  finally
    TreeView1.Items.EndUpdate;
  end;
end;

Open in new window

... on creating node I allocate memory for null terminated string and this memory should be released on delete node. So add OnDeletation event to TreeView:

procedure TForm1.TreeView1Deletion(Sender: TObject; Node: TTreeNode);
var
  ptr: Pointer;
begin
  ptr := Node.Data;
  if Assigned(ptr) then
  begin
    Node.Data := nil;
    FreeMemory(ptr);
    ptr := nil;
  end;
end;

Open in new window

hrvica5

ASKER

Thank you very much for soultions but I have 2 problems

TUC is ok,
but under first node BRE, it is not OK (treeview.jpg)

2. If I have 1000 rows it slow is slow (duration.jpg)

Thank you very much and sory
duration.jpg
TreeView.jpg

Sinisa Vuk

Ahhh. It is slow because of bad finding root node algorithm. Made some changes. Now I extract part of finding root to get top most root, then go deeper and find next root same way.

function GetLevelId(FindIdStr: AnsiString; iLevel: Integer): String;
var
  i, j: Integer;
begin
  Result := '';

  j := 0;
  for i:=1 to Length(FindIdStr) do
  begin
    if j<=iLevel then
    begin
      if FindIdStr[i] = '.' then
      begin
        Inc(j); //count points
      end
      else
        Result := FindIdStr[i] + Result;
    end
    else
      Break;
  end;
end;

procedure FindRootNode(RootNode: TTreeNodes; FindIdStr: AnsiString; iLevel: Integer;
  var node: TTreeNode);
var
  i: Integer;
  sNodeStr, FindIdRoot: AnsiString;
  bGoDeeper: Boolean;
begin
  if Assigned(RootNode) then
  begin
    //don't compare all nodes but use find first root logic
    FindIdRoot := GetLevelId(FindIdStr, iLevel); //get pre-root id
    bGoDeeper := Length(FindIdRoot) < Length(FindIdStr); //need to go deeper in tree

    //find first id for root and go deeper using this line
    for i := 1 to RootNode.Count do
    begin
      sNodeStr := String(PAnsiChar(RootNode.Item[i-1].Data));
      if sNodeStr = FindIdRoot then //compare to root
      begin
        if bGoDeeper then
        begin
          FindRootNode(TTreeNodes(RootNode.Item[i-1]), FindIdStr, iLevel+1, node); //go deeper to level+1
        end
        else
        begin
          node := RootNode.Item[i-1];
          Break;
        end;
      end;

      if Assigned(node) then Break;
    end;
  end;
end;

procedure TForm1.BitBtn1Click(Sender: TObject);
var
  Node, rootNode: TTreeNode;
  parentId, nodeId: AnsiString;
  ptr: PAnsiChar;
begin
  data.First; //sort by parentid, id

  TreeView1.Items.BeginUpdate;
  try
    TreeView1.Items.Clear;

    while not data.Eof do
    begin
      parentId := data.FieldByName('parentNode').AsString;
      nodeId := data.FieldByName('node').AsString;

      rootNode := nil;
      FindRootNode(TreeView1.Items, parentId, 0, rootNode); //always go from level 0

      ptr := GetMemory(Length(nodeId)+1); //null termnated string
      ZeroMemory(ptr, Length(nodeId)+1);
      StrPCopy(ptr, nodeId);

      if Assigned(rootNode) then
        Node := TreeView1.Items.AddChildObject(rootNode, data.FieldByName('code').AsString, ptr)
      else
        Node := TreeView1.Items.AddObject(rootNode, data.FieldByName('code').AsString, ptr);

      data.Next;
    end;
  finally
    TreeView1.Items.EndUpdate;
  end;
end;

procedure TForm1.TreeView1Deletion(Sender: TObject; Node: TTreeNode);
var
  ptr: Pointer;
begin
  ptr := Node.Data;
  if Assigned(ptr) then
  begin
    Node.Data := nil;
    FreeMemory(ptr);
    ptr := nil;
  end;
end;

Open in new window

fixed finding right node too.

Geert G

fwiw,
the whole point of sorting and the stack is that it's not necessary to look for any parent/sub/child node
there is no point in sorting (or using a stack) when you do the lookups and move around in the tree

so if lookups are done, don't sort the data
> sorting the data slows down retreiving the query

use either the sorting+stack
or the lookups

don't use both !

hrvica5

ASKER

Thank you very much