How to eliminate variables “panel1, panel2, panel3 .. etc.” in Delphi?

2
votes

i have this type 

type
 TMain = class(TForm)

 panel1: Tpanel;
 panel2: Tpanel;
 panel3: Tpanel;
 panel4: Tpanel;
 panel5: Tpanel;
 panel6: Tpanel;
 panel7: Tpanel;
 panel8: Tpanel;
 ......
 panel45: Tpanel;

 label1: TLabel;
 label2: TLabel;
 label3: TLabel;
 label4: TLabel;
 label5: TLabel;
 label6: TLabel;
 label7: TLabel;
 ...........
 label109: TLabel;

How can i call this components in one line... inside the Type?

Thank you ...

UpDate....

Base from the anwser i get and accepted it works great when i have all this components and make the actions like a button1.click from the main form...

But i use to make the actions from units... so

When i click a button i great a procedure DoMaths(Sender: TObject);

procedure Tform1.DoMaths(Sender: TObject);
  begin
    if TButton1(Sender).hint := 'Make the standard Package' then
      do_Maths_standard_package;
  end;

the do_Maths_standard_package is in unit ComplexMaths.

is the procedure do_Maths_standard_package form unit ComplexMaths it calls some components form Form1... like Form1.label1 etc...

So when i call the RegisterClass(TLabel) and erase the Tlabel from the type it gives an error that it cant find the Label1...

Please can someone help me so not to do the hole program from the start...

Thank you again...

3
delphioptimizationdelphi-7
I suggest you to transform the update part in a new question... – Fabricio Araujo
I make a flag for this Fabricio with comment to moderators if i can do it in a new question or update the existed one no awnser yet... so wait and see... – azrael11

3 Answers

7
votes

You can delete the name of a TPanel or TLabel then it only exists in the Controls List not in the Type declaration of the form. You either need to leave one Label and one panel or add: 

initialization
  RegisterClass(TPanel);
  RegisterClass(Tlabel);
end.

at the end of the form.

This makes forms with a lot of controls much neater.

5
votes

Use the TForm.Controls array:

var
  i: Integer;
  Pnl: TPanel;
begin
  for i := 0 to ControlCount - 1 do
    if Controls[i] is TPanel then
    begin
      Pnl := TPanel(Controls[i]);
      Pnl.Caption := 'This is panel ' + IntToStr(i);
    end;
end;

Delphi automatically creates two lists for each TWinControl:

  • Controls contains a list of all TControl items the control contains.

  • Components is a list of all the TComponents on a control.

Note that all Controls are Components, but not all Components are Controls; that's why there are two lists. (A TDataSet, for instance, is in the Components list, but not in the Controls list; a TEdit, on the other hand, will be in both.)

You can use the same technique to iterate through the components on a panel or other container as well - TPanel has both Control and Component arrays, for instance.

If what you actually want is to reduce the number of items inside the type declaration itself, create them at runtime instead - Delphi will automatically add them to the arrays based on the Owner and Parent:

procedure TForm1.FormCreate(Sender: TObject);
var
  i: Integer;
  Panel: TPanel;
  Label: TLabel;
begin
  for i := 0 to 10 do
  begin
    Panel := TPanel.Create(Self);  // Set who frees it
    Panel.Parent := Self;   // Set display surface
    Panel.Align := alTop;
    Panel.Name := Format('Panel%d', [i]); // Not necessary
    Panel.Caption := Panel.Name;  

    // Add a label on each panel, just for fun.
    Label := TLabel.Create(Panel); // Panel will free label
    Label.Parent := Panel;         // Label will show on panel
    Label.Top := 10;
    Label.Left := 10;
    Label.Name := Format('Label%d', [i]);
    Label.Caption := Label.Caption;   // Not necessary
  end;
end;

Note that creating them yourself is not an "optimization", as it just shifts the loading from the VCL doing it to you doing it yourself. It will reduce the size of the .dfm file, but won't speed up your code or loadtime any, and it means you can't visually lay out the form as well. (It's also much harder to maintain your code, because your controls have meaningless names. It's much easier to know what LastNameEdit or EditLastName is than Edit1 when you read the code 6 months from now.)

2
votes

You can use arrays:

panels : array[1..45] of TPanel;

This would allow you to create an array of your controls, and access and use them by index.