TMemo gives stranges black area when using scrollbars

[rolandvh]

Hi,

I'm using free vision and I'm using a TMemo in a dialog window. I give the memo 2 scrollbars and a indicator as you can see in the code below:

Code: Pascal  [Select][+][-]

1. // Menu Discription
2.     R.Assign(3, 14, 48, 15);
3.     MemoHScrollBar := New(PScrollbar, Init(R));
4.     R.Assign(50, 7, 51, 14);
5.     MemoVScrollBar := New(PScrollbar, Init(R));
6.     Insert(MemoHScrollBar);
7.     Insert(MemoVScrollBar);
8.     R.Assign(48, 14, 51, 15);
9.     MemoIndicator := New(PIndicator, Init(R));
10.     Insert(MemoIndicator);
11.     R.Assign(3,7,50,14);
12.     PMemoMenuDescription:=New(PMemo,Init(R, MemoHScrollBar, MemoVScrollBar, MemoIndicator, 10000));
13.     PMemoMenuDescription^.Limit.X := 70;
14.     PMemoMenuDescription^.Limit.Y := 40;
15.     Insert(PMemoMenuDescription);
16.     R.Assign(3,6,32,7);
17.     Insert(New(PLabel, Init(R,'~D~iscription menu ', PMemoMenuDescription)));
18.  

When I type in the memo field and I get past the width of the field I get a strange black box and characters are repeated. Often I also get an error message after I close the application when this happens.  Error code 216 (general protection fault). I just can't see what I'm doing wrong. See the attachment.
This happens under windows 10 and linux
Thanks for any replies.

[rolandvh]

To make it all a little simpler to test I made a simple program. Could it be a bug in TMemo?

Code: Pascal  [Select][+][-]

1. program errormemo;
2. uses App, Menus, dialogs, drivers, views, objects, editors;
3. type
4.    TMyApp = OBJECT(TApplication)
5.         constructor init;
6.         procedure HandleEvent(var aEvent : TEvent); virtual;
7.         procedure MakeMemoDialog;
8.         procedure InitMenuBar; virtual;
9.    end;
10.  
11.  
12. var
13.         MyApp: TMyApp;
14. const cmMemoDialog = 1000;
15.  
16. constructor TMyApp.init;
17. begin
18.         inherited init;
19. end;
20.  
21. procedure TMyApp.InitMenuBar;
22. var R : TRect;
23. begin
24.        GetExtent(R);
25.         R.B.Y := R.A.Y + 1;
26.         MenuBar := New(PMenubar, Init(R, NewMenu(NewSubMenu('~M~emo test',  hcNoContext,
27.                                                  NewMenu(
28.                                                  NewItem('Test', 'F2', kbF2, cmMemoDialog, hcNoContext, nil)),nil))));
29. end;
30.  
31. procedure TMyApp.HandleEvent(var aEvent : TEvent);
32. begin
33.         inherited HandleEvent(aEvent);
34.         if aEvent.What = evCommand then begin
35.           case aEvent.Command of
36.             cmMemoDialog:
37.             begin
38.                 MakeMemoDialog;
39.             end
40.             else
41.             begin
42.                 Exit;
43.             end;
44.           end;
45.     end;
46.     ClearEvent(aEvent);
47.  
48. end;
49.  
50. procedure TMyApp.MakeMemoDialog;
51. var
52.     D: PDialog;
53.     R: TRect;
54.     rs: word;
55.     aVScrollBar : PScrollBar;
56.     aHScrollBar : PScrollBar;
57.     aIndicator : PIndicator;
58.     aMemo : PMemo;
59. begin
60.     GetExtent(R);
61.     R.A.X := R.A.X + 4;
62.     R.A.Y := R.A.Y + 1;
63.     R.B.X := R.B.X - 4;
64.     R.B.Y := R.B.Y - 4;
65.     D := New(PDialog, Init(R, 'Test memo'));
66.  
67.     R.A.X := 3;
68.     R.A.Y := 10;
69.     R.B.X := 60;
70.     R.B.Y := 11;
71.     aHScrollBar := New(PScrollbar, Init(R));
72.     D^.Insert(aHScrollBar);
73.  
74.     R.A.X := 60;
75.     R.A.Y := 3;
76.     R.B.X := 61;
77.     R.B.Y := 10;
78.     aVScrollBar := New(PScrollBar, Init(R));
79.     D^.Insert(aVScrollBar);
80.  
81.     R.A.X := 61;
82.     R.A.Y := 7;
83.     R.B.X := 64;
84.     R.B.Y := 8;
85.     aIndicator := New(PIndicator, Init(R));
86.     D^.Insert(aIndicator);
87.  
88.     R.A.X := 3;
89.     R.A.Y := 3;
90.     R.B.X := 60;
91.     R.B.Y := 10;
92.     aMemo := New(PMemo, Init(R, aHScrollBar, aVScrollBar, aIndicator, 10000));
93.     aMemo^.Limit.X := 70;
94.     aMemo^.Limit.Y := 40;
95.     D^.Insert(aMemo);
96.  
97.  
98.     rs := Desktop^.ExecView(D);
99.     Dispose(D, Done);
100.  
101. end;
102.  
103. begin
104.   MyApp.Init;
105.   MyApp.Run;
106.   MyApp.Done;
107. end.
108.  

[TRon]

Hi rolandvh,

please be so kind to edit your first two posts and enclose your code with code tags, see: https://wiki.freepascal.org/Forum#Use_code_tags

edit: thank you   

edit2: and i am able to confirm (not that i have any knowledge code-wise on fv)

[rolandvh]

Thank you for your reply.  Could be a bug then. Would be nice if someone could confirm this with the right knowledge of fv. But maybe I should report it in the bugtracker anyway.