Lazarus

Programming => General => Topic started by: Jvan on August 18, 2020, 06:08:26 am

Title: StringGrid: How to avoid moving rows over/under some rows?
Post by: Jvan on August 18, 2020, 06:08:26 am

This is the situation:
I have a Grid with 9 rows, with "goRowMoving" property in True. But I need this constraint: rows that are from 1 to 5 can only be  moved among them, and rows that are from 6 to 9 can only be moved among them.

So, I have this code:

Code: Pascal  [Select][+][-]

1.  
2. procedure TForm1.StringGrid1ColRowMoved(Sender: TObject; IsColumn: Boolean;
3.   sIndex, tIndex: Integer);
4. begin
5.  
6.   if not(IsColumn) then begin  //Only rows
7.     if (sIndex <= 5) and (tIndex > 5) then
8.       //AVOID MOVING    
9.     else if (sIndex > 5) and (tIndex <= 5) then
10.       //AVOID MOVING
11.   end;
12.  
13.  
14. end;
15.  
16.  

But what code must I use to avoid moving the selected row (sIndex) in that cases?

Title: Re: StringGrid: How to avoid moving rows over/under some rows?
Post by: Handoko on August 18, 2020, 06:42:39 am

Can you tell us what program you are currently building?

You can use a TTimer to move user active cell to wherever you want, which also means to move them back if they try to access non-allowed location.

It's not exactly what you want but with some modification it should work, here is the discussion:
https://forum.lazarus.freepascal.org/index.php/topic,37286.msg250229.html (https://forum.lazarus.freepascal.org/index.php/topic,37286.msg250229.html)

Title: Re: StringGrid: How to avoid moving rows over/under some rows?
Post by: Jvan on August 18, 2020, 09:27:31 pm

Quote from: Handoko on August 18, 2020, 06:42:39 am

Can you tell us what program you are currently building?

You can use a TTimer to move user active cell to wherever you want, which also means to move them back if they try to access non-allowed location.

It's not exactly what you want but with some modification it should work, here is the discussion:
https://forum.lazarus.freepascal.org/index.php/topic,37286.msg250229.html (https://forum.lazarus.freepascal.org/index.php/topic,37286.msg250229.html)

An accounting software-

Title: Re: StringGrid: How to avoid moving rows over/under some rows?
Post by: winni on August 18, 2020, 09:37:01 pm

Hi!

Just filter out the possible combinations.
The illegal combinations are avoided.

Code: Pascal  [Select][+][-]

1.  
2. procedure TForm1.StringGrid1ColRowMoved(Sender: TObject; IsColumn: Boolean;
3.   sIndex, tIndex: Integer);
4. const set1 = [1..5];
5.          set2= [6 ..9];
6. begin
7.  
8.   if not(IsColumn) then
9.      begin  //Only rows
10.     if ((sIndex in Set1) and (tIndex in Set1) )
11.       OR
12.   ((sIndex in Set2) and (tIndex in Set2)) then
13.     begin
14.       // MOVE!!!
15.      end;
16.   end;
17.  
18. end;

Winni

Title: Re: StringGrid: How to avoid moving rows over/under some rows?
Post by: Blaazen on August 18, 2020, 09:45:55 pm

Winni: This won't help. The row is moved and then is triggered event. You cannot restrict the move from the event.

Title: Re: StringGrid: How to avoid moving rows over/under some rows?
Post by: Handoko on August 18, 2020, 09:49:25 pm

Quote from: Jvan on August 18, 2020, 09:27:31 pm

An accounting software-

That explains why you need a powerful grid. Maybe you can consider this:

http://www.scalabium.com/smdbgrid.htm

Unfortunately it is not for Lazarus.

Title: Re: StringGrid: How to avoid moving rows over/under some rows?
Post by: winni on August 18, 2020, 09:56:59 pm

Quote from: Blaazen on August 18, 2020, 09:45:55 pm

Winni: This won't help. The row is moved and then is triggered event. You cannot restrict the move from the event.

Thanx Blaazen!

Arghhh! I forgot that.

So you have to do it the hard way:
Whenever something changes in the Grid  make an Undo-Copy before the action.
If the row exchange is a unwanted make an Undo.
Sounds like a lot of work.

Winni

Title: Re: StringGrid: How to avoid moving rows over/under some rows?
Post by: Scoops on August 18, 2020, 10:03:44 pm

Depending on your data, why not use 2 stringgrids one with 5 rows the other with 4, even place them together to resemble only one grid ? I did this once and it works ok, but like i said it depends on your data.
read you first 5 lines then 4 etc etc. just looping through your data to split between stringgrids.

Title: Re: StringGrid: How to avoid moving rows over/under some rows?
Post by: Blaazen on August 18, 2020, 10:07:33 pm

If those moves should be done by mouse only, I would use OnMouseDown/Up events and manage it myself and by-pass built in row moving completly.

Title: Re: StringGrid: How to avoid moving rows over/under some rows?
Post by: Jvan on August 18, 2020, 10:16:19 pm

Well, my explanation is only an example. The grid could contain many groups of rows and that rows must be only exchanged between rows of the same group.

Title: Re: StringGrid: How to avoid moving rows over/under some rows?
Post by: winni on August 18, 2020, 10:17:06 pm

Hi!

I can enhance my source to switch the rows back:

Code: Pascal  [Select][+][-]

1. procedure TForm1.StringGrid1ColRowMoved(Sender: TObject; IsColumn: Boolean;
2.   sIndex, tIndex: Integer);
3. const set1 = [1..5];
4.          set2= [6 ..9];
5. begin
6.  
7.   if not(IsColumn) then
8.      begin  //Only rows
9.     if
10.    NOT (
11.     ((sIndex in Set1) and (tIndex in Set1) )
12.       OR
13.      ((sIndex in Set2) and (tIndex in Set2))
14.    )
15.   then
16.     begin
17.       StringGrid1.MoveColRow(false, tIndex,sIndex);
18.      end;
19.   end;
20.  
21. end;
22.  

Winni

Title: Re: StringGrid: How to avoid moving rows over/under some rows?
Post by: Jvan on August 18, 2020, 10:19:35 pm

What about the OnColRowExchanged event? How to exchange rows by code? I just thought I can exchange rows after the OnColRowMoved event.

Title: Re: StringGrid: How to avoid moving rows over/under some rows?
Post by: Blaazen on August 18, 2020, 10:24:34 pm

So managing Row moving by code is quite easy. It needs just two events (OnMouseDown/Up) and one global var.

Code: Pascal  [Select][+][-]

1. procedure TForm18.StringGrid1MouseDown(Sender: TObject; Button: TMouseButton; Shift: TShiftState; X, Y: Integer);
2. var aPt: TPoint;
3. begin
4.   aPt:=StringGrid1.MouseToCell(Point(X, Y));
5.   if aPt.X=0 then
6.     begin
7.       writeln('From', aPt.Y);
8.       ReadyRow:=aPt.Y;
9.     end else
10.     ReadyRow:=-1;
11. end;
12.  
13. procedure TForm18.StringGrid1MouseUp(Sender: TObject; Button: TMouseButton; Shift: TShiftState; X, Y: Integer);
14. var aPt: TPoint;
15. begin
16.   aPt:=StringGrid1.MouseToCell(Point(X, Y));
17.   if (aPt.X=0) and (ReadyRow>0) then
18.     begin
19.       writeln('To', aPt.Y);
20.       StringGrid1.MoveColRow(False, ReadyRow, aPt.Y);
21.     end;
22.   ReadyRow:=-1;
23. end;

With this, you can move rows by dragging on the leftmost column.

Title: Re: StringGrid: How to avoid moving rows over/under some rows?
Post by: Jvan on August 18, 2020, 10:29:46 pm

Quote from: winni on August 18, 2020, 10:17:06 pm

Hi!

I can enhance my source to switch the rows back:

Code: Pascal  [Select][+][-]

1. procedure TForm1.StringGrid1ColRowMoved(Sender: TObject; IsColumn: Boolean;
2.   sIndex, tIndex: Integer);
3. const set1 = [1..5];
4.          set2= [6 ..9];
5. begin
6.  
7.   if not(IsColumn) then
8.      begin  //Only rows
9.     if
10.    NOT (
11.     ((sIndex in Set1) and (tIndex in Set1) )
12.       OR
13.      ((sIndex in Set2) and (tIndex in Set2))
14.    )
15.   then
16.     begin
17.       StringGrid1.MoveColRow(false, tIndex,sIndex);
18.      end;
19.   end;
20.  
21. end;
22.  

Winni

I had the error of the image.

Title: Re: StringGrid: How to avoid moving rows over/under some rows?
Post by: Jvan on August 18, 2020, 10:59:33 pm

Quote from: Blaazen on August 18, 2020, 10:24:34 pm

So managing Row moving by code is quite easy. It needs just two events (OnMouseDown/Up) and one global var.

Code: Pascal  [Select][+][-]

1. procedure TForm18.StringGrid1MouseDown(Sender: TObject; Button: TMouseButton; Shift: TShiftState; X, Y: Integer);
2. var aPt: TPoint;
3. begin
4.   aPt:=StringGrid1.MouseToCell(Point(X, Y));
5.   if aPt.X=0 then
6.     begin
7.       writeln('From', aPt.Y);
8.       ReadyRow:=aPt.Y;
9.     end else
10.     ReadyRow:=-1;
11. end;
12.  
13. procedure TForm18.StringGrid1MouseUp(Sender: TObject; Button: TMouseButton; Shift: TShiftState; X, Y: Integer);
14. var aPt: TPoint;
15. begin
16.   aPt:=StringGrid1.MouseToCell(Point(X, Y));
17.   if (aPt.X=0) and (ReadyRow>0) then
18.     begin
19.       writeln('To', aPt.Y);
20.       StringGrid1.MoveColRow(False, ReadyRow, aPt.Y);
21.     end;
22.   ReadyRow:=-1;
23. end;

With this, you can move rows by dragging on the leftmost column.

The rows don't move with up/down keys and I have an error when clicking the row header.

Code: Pascal  [Select][+][-]

1.  
2. unit Unit1;
3.  
4. {$mode objfpc}{$H+}
5.  
6. interface
7.  
8. uses
9.   Classes, SysUtils, Forms, Controls, Graphics, Dialogs, Grids;
10.  
11. type
12.  
13.   { TForm1 }
14.  
15.   TForm1 = class(TForm)
16.     StringGrid1: TStringGrid;
17.     procedure StringGrid1MouseDown(Sender: TObject; Button: TMouseButton;
18.       Shift: TShiftState; X, Y: Integer);
19.     procedure StringGrid1MouseUp(Sender: TObject; Button: TMouseButton;
20.       Shift: TShiftState; X, Y: Integer);
21.   private
22.  
23.   public
24.  
25.   end;
26.  
27. var
28.   Form1: TForm1;
29.   ReadyRow: Integer;
30.  
31. implementation
32.  
33. {$R *.lfm}
34.  
35. { TForm1 }
36.  
37.  
38.  
39. procedure TForm1.StringGrid1MouseDown(Sender: TObject; Button: TMouseButton;
40.   Shift: TShiftState; X, Y: Integer);
41. var aPt: TPoint;
42. begin
43.   aPt:=StringGrid1.MouseToCell(Point(X, Y));
44.   if aPt.X=0 then
45.     begin
46.       writeln('From', aPt.Y);
47.       ReadyRow:=aPt.Y;
48.     end else
49.     ReadyRow:=-1;
50. end;
51.  
52. procedure TForm1.StringGrid1MouseUp(Sender: TObject; Button: TMouseButton;
53.   Shift: TShiftState; X, Y: Integer);
54. var aPt: TPoint;
55. begin
56.   aPt:=StringGrid1.MouseToCell(Point(X, Y));
57.   if (aPt.X=0) and (ReadyRow>0) then
58.     begin
59.       writeln('To', aPt.Y);
60.       StringGrid1.MoveColRow(False, ReadyRow, aPt.Y);
61.     end;
62.   ReadyRow:=-1;
63. end;
64.  
65. end.    
66.  

Title: Re: StringGrid: How to avoid moving rows over/under some rows?
Post by: Jvan on August 18, 2020, 11:21:23 pm

Finally, I did it.

Code: Pascal  [Select][+][-]

1. procedure TForm1.StringGrid1ColRowMoved(Sender: TObject; IsColumn: Boolean;
2.   sIndex, tIndex: Integer);
3. begin
4.   if not(IsColumn) and (StringGrid1.Tag = 0) then begin  //Only rows
5.     if (sIndex <= 5) and (tIndex > 5) then begin
6.       //AVOID MOVING
7.       StringGrid1.Tag := 1;
8.       ShowMessage('Error: La fila que desea mover no corresponde al grupo de su nuevo lugar.');
9.       StringGrid1.MoveColRow(false, tIndex, sIndex);
10.       StringGrid1.Tag := 0;
11.     end else if (sIndex > 5) and (tIndex <= 5) then begin
12.       //AVOID MOVING
13.       StringGrid1.Tag := 1;
14.       ShowMessage('Error: La fila que desea mover no corresponde al grupo de su nuevo lugar.');
15.       StringGrid1.MoveColRow(false, tIndex, sIndex);
16.       StringGrid1.Tag := 0;
17.     end;
18.   end;
19. end;
20.  
21.