asked on

RunTime Labels

I created an array of Labels at runtime.

LNames: TList;

procedure...
var L: TLabel; I: Integer;
begin
for I := 0 to 9 do
begin
L := TLabel.Create(Form1);
L.Parent := Scroll; // Scroll is a scrollbox
L.Top := 16;
L.Left := 60;
L.Caption := 'Name';
LNames.Add(L);
end;
end;

2 Questions...
Note: If I try to LNames.Clear I get a Access Violation.
I do destroy the list at Form1.Destroy

1)How do I get change the values of the labels?
-- LNames[0].Caption = 'Somthing else'; // wrong

2)How do I release any or all of the Label?
-- LNames[9].Free // wrong

Don

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nnbbb09

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h_mohsenian

dear d32coder,

this code has not error but i dont can help u or not?

procedure TForm1.Button1Click(Sender: TObject);
var L: TLabel; I: Integer;
begin
try
LNames := TList.Create;
LNames.Clear;
for I := 0 to 9 do
begin
L := TLabel.Create(Form1);
L.Parent := ScrollBar1; // Scroll is a scrollbox
L.Top := 16;
L.Left := 60;
L.Caption := 'Name';
LNames.Add(L);
end; // for

// for Caption u must use (LNames.Items[i]) but i dont know it exactly

LNames.Clear;

// just do all of ur needs here
// ..
// ..
finally
LNames.Destroy;
end;

end;

best regards
hamed

h_mohsenian

nnbbb09 code helped me:
TLabel(LNames[0]).caption := 'hamed' is true or at least
better than (LNames.Items[i]).

hamed

d32coder

ASKER

Lnames is declared as a Global and is created in Form.Create.

I'm trying your code now.

bbiab

d32coder

ASKER

I liked the TComponentList thing.

If we can change the question to that topic I'd appreciate it.

I'm trying this... CList is my TComponentList and is global. Created in Form.Create and Freed in Form.Destroy

procedure...
var L: TLabel;
begin
L := TLabel.Create(Form1);

L.Caption := 'a';
CList.Add(L);
L.Caption := 'b';
CList.Add(L);
end;

I know this is wrong because the pointers in the CList point to the same component...

My goal create as many Labels as needed at runtime (unknown number at design time but it could be as many as 100).

I need to be able to edit the properties of each label ..
TLabel(CList[a]).Caption := 'c';

...and to remove them all when needed.
for i := 0 to CList.Count -1 do Clist.Remove(CList.First);

Having said all of that...

Please show me how to declare L so that I can add multiple instances of it insterad of overwriting the previous instance with a second call to CList.Add...

Even Better.. CList.Add(TLabel.Create(form1)); ???
This is becoming more complicated so I'll up the points.

Thanks to all you for being so patient.

Don

d32coder

ASKER

I figured out the ComponentList but would have never explored it without your comment.

Thanks
Don