[Solved] - My First Class - Access violation when setting private var

[Wilko500]

My first (failed) attempt at understanding and creating a class having read the Class documentation. My code compiles but on running in Lazarus IDE fails on any attempt to reference a private var, a Sigsegv error, when running without IDE Access Violation error. Please can someone tell me where I am going wrong.

My Class Unit

Code: Pascal  [Select][+][-]

1. unit ClsChartSettings;
2.  
3. {$mode objfpc}{$H+}
4.  
5. interface
6.  
7. Type
8.     TChSet = Class
9. Private
10.     PageHt:    Single;   //Private var to hold Page Height
11.  
12. Procedure SetHt(PgHt: Single);  //Private proc to set Page Height
13.  
14. Public
15.  
16. constructor Create(ChId : String);
17. Property PageH: Single Read PageHt Write SetHt;   //Public property read from private var
18.                                                   //Write with proc SetHt
19. End;
20.  
21. implementation
22. uses
23.     Classes, SysUtils, Dialogs;
24.  
25. constructor TChSet.Create(ChId: String);
26. //Initialise class variable
27. begin
28. PageHt:=0;
29. ShowMessage('Class Created ' + ChId);
30. End;
31.  
32. Procedure TChSet.SetHt(PgHt: Single);
33. //This proc to set private var
34. Begin
35. PageHt:=PgHt;
36. End;
37.  
38. end.
39.  

My Test program

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.   ClsChartSettings;
10.  
11. type
12.  
13.   { TForm1 }
14.  
15.   TForm1 = class(TForm)
16.     Button1: TButton;
17.     Edit1: TEdit;
18.     Edit2: TEdit;
19.     Edit3: TEdit;
20.     Edit4: TEdit;
21.     Label1: TLabel;
22.     Label2: TLabel;
23.     Label3: TLabel;
24.     Label4: TLabel;
25.     Label5: TLabel;
26.     procedure Button1Click(Sender: TObject);
27.   private
28.  
29.   public
30.  
31.   end;
32.  
33. var
34.   Form1: TForm1;
35.  
36. implementation
37.  
38. {$R *.lfm}
39.  
40. { TForm1 }
41.  
42. procedure TForm1.Button1Click(Sender: TObject);
43. var
44.   x:      TChSet;
45. begin
46.   x.Create('Test');
47.   x.PageH:=297;
48.   ShowMessage(x.PageH.ToString);
49. end;
50.  
51. end.
52.  

[Blaazen]

Code: Pascal  [Select][+][-]

1. var
2.   x:      TChSet;
3. begin
4.   x:=TChSet.Create('Test');

[dseligo]

And put this at the end:

Code: Pascal  [Select][+][-]

1. x.Free;

[Wilko500]

Well that was easy.  Thanks.  I should have spotted that but evidently couldn't see for looking . Thanks also for noting the need for x.Free. I was aware but lazy coding while focussed on the error.