Make a part of text of a TLabeledEdit to keep "in sync" with another one's Text

[vico]

Hello!

I'm making this form: <image in attachment>

the "caminho" TLabeledEdit will be composed of the user home dir + whatever is in "nome_pasta" TLabelEdit Text property.

The unit associated with the form:

Code: Pascal  [Select][+][-]

1. unit u_novo_projeto;
2.  
3. {$mode ObjFPC}{$H+}
4.  
5. interface
6.  
7. uses
8.   Classes, SysUtils, Forms, Controls, Graphics, Dialogs, ExtCtrls, StdCtrls;
9.  
10. type
11.  
12.   { Tf_novo_projeto }
13.  
14.   Tf_novo_projeto = class(TForm)
15.     btn_explorar: TButton;
16.     btn_cancelar: TButton;
17.     btn_ok: TButton;
18.     caminho: TLabeledEdit;
19.     dlg_pasta_projeto: TSelectDirectoryDialog;
20.     titulo: TLabeledEdit;
21.     nome_pasta: TLabeledEdit;
22.     procedure btn_cancelarClick(Sender: TObject);
23.     procedure btn_explorarClick(Sender: TObject);
24.     procedure FormCreate(Sender: TObject);
25.     procedure nome_pastaKeyPress(Sender: TObject; var Key: char);
26.   private
27.  
28.   public
29.  
30.   end;
31.  
32. var
33.   f_novo_projeto: Tf_novo_projeto;
34.  
35. implementation
36.  
37. {$R *.lfm}
38.  
39. { Tf_novo_projeto }
40.  
41. procedure Tf_novo_projeto.btn_cancelarClick(Sender: TObject);
42. begin
43.   f_novo_projeto.Close;
44. end;
45.  
46. procedure Tf_novo_projeto.btn_explorarClick(Sender: TObject);
47. begin
48.   if dlg_pasta_projeto.Execute then
49.     caminho.Text := dlg_pasta_projeto.FileName + '\\' + nome_pasta.Text;
50. end;
51.  
52. procedure Tf_novo_projeto.FormCreate(Sender: TObject);
53. begin
54.   caminho.Text:=GetUserDir() + nome_pasta.Text;
55.   dlg_pasta_projeto.InitialDir:=GetUserDir();
56.   dlg_pasta_projeto.FileName:=GetUserDir();
57. end;
58.  
59. procedure Tf_novo_projeto.nome_pastaKeyPress(Sender: TObject; var Key: char);
60. begin
61.  
62. end;
63.  
64. end.
65.  

I want to know if is possible to, whenever the user changes the Text on "nome_pasta" (either adding more text, deleting, etc) to automatically "update" the Text of "caminho", replacing the earlier appended value of nome_pasta to the new contents (keeping the prefix, by default the home dir, intact)

[jamie]

use the OnChange Event that gets invoked each time you change something in the text.

to change the other control's appearance, you can use the OtherControl.Caption := ????

The caption property is what you need to use.

[cdbc]

Hi
What jamie said and remember that all components implement IObserved, but maybe that's overkill 
Regards Benny

[KodeZwerg]

Code: Pascal  [Select][+][-]

1. unit Unit1;
2.  
3. {$mode objfpc}{$H+}
4.  
5. interface
6.  
7. uses
8.   Classes , SysUtils , Forms , Controls , Graphics , Dialogs , StdCtrls;
9.  
10. type
11.  
12.   { TForm1 }
13.  
14.   TForm1 = class(TForm)
15.     Edit1: TEdit;
16.     Edit2: TEdit;
17.     procedure Edit1Change(Sender: TObject);
18.     procedure FormCreate(Sender: TObject);
19.   private
20.     Edit1Text: string;
21.     Edit2Text: string;
22.   public
23.  
24.   end;
25.  
26. var
27.   Form1: TForm1;
28.  
29. implementation
30.  
31. {$R *.lfm}
32.  
33. { TForm1 }
34.  
35. procedure TForm1.FormCreate(Sender: TObject);
36. begin
37.   // store original values
38.   Edit1Text := Edit1.Caption;
39.   Edit2Text := Edit2.Caption;
40. end;
41.  
42. procedure TForm1.Edit1Change(Sender: TObject);
43. begin
44.   // simple append any changes
45.   Edit1Text := Edit1.Caption;
46.   Edit2.Text := Edit2Text + Edit1Text;
47. end;
48.  
49. end.

[howardpc]

The attached project example uses a TLabeledEdit, so may be more immediately helpful.

Note that information retrieved by GetUserDir at program stsrt might well change thereafter without your knowing, because of what the user might do elsewhere. In other words don't rely on it always remaining as what you assume it to be.

[vico]

I was able to solve my problem with the OnChange event. Thank you so much!

BTW, here's the end result in the unit for information, since i'm working on the project on Github.