[Solved] Colors in a DBGrid [Yes Really]

[madref]

Is it possible to have color columns in a DBGrid?
In my example where the 'X' is?

[Handoko]

I haven't tried but I think it is possible. Because TDBGrid has OnPrepareCanvas event, which can be used to change its color when painting.

See my example on TStringGrid here, maybe you can adapt it to TDBGrid:
http://forum.lazarus.freepascal.org/index.php/topic,37181.msg249361.html#msg249361

[wp]

Is it possible to have color columns in a DBGrid?
In my example where the 'X' is?

I don't understand: You want to colorize individual columns, but the 'X's are in individual cells.

For the entire columns you can adjust the Color property of each TColumn. For the individual cells you should follow Handoko's post and use the OnPrepareCanvas event in which you can specify any Canvas properties dependant on data values.

[madref]

When i try to use this

Code: Pascal  [Select][+][-]

1. procedure TForm_Wedstrijden_Overzicht.DBGrid_WedstrijdenPrepareCanvas(
2.   sender: TObject; DataCol: Integer; Column: TColumn; AState: TGridDrawState);
3. begin
4.  
5.  
6. end;    

I get an internal error 200611031


What is that???


[Found out why !!!]
i was doing this in another unit and it's completely 100% Delphi but not Lazarus.

Code: Pascal  [Select][+][-]

1. function SingleQuotedStr (St: String) : String;
2. begin
3.   SingleQuotedStr := Chr(39)+ St + Chr(39);
4. end;    // SingleQuotedStr  

and it should be:

Code: Pascal  [Select][+][-]

1. function SingleQuotedStr (St: String) : String;
2. begin
3.   Result := Chr(39)+ St + Chr(39);
4. end;    // SingleQuotedStr  

[Handoko]

Can you provide the whole compilable code for us to test? If you're not willing to publicize the project, you can write a sample project that show the error.

I put this code below on my test project, I didn't get the problem like yours:

Code: Pascal  [Select][+][-]

1. procedure TfrmProduk.DBGrid1PrepareCanvas(sender: TObject; DataCol: Integer;
2.   Column: TColumn; AState: TGridDrawState);
3. begin
4.   //
5. end;

[madref]

Hmmm..... this is really strange.


I have made a skeleton version of my database so i could put it up here so that you all can try and solve my problem.
But while doing so i found the solution myself with the following code:

Code: Pascal  [Select][+][-]

1. procedure TForm_Wedstrijden_Overzicht.DBGrid_WedstrijdenPrepareCanvas(
2.   sender: TObject; DataCol: Integer; Column: TColumn; AState: TGridDrawState);
3. begin
4.   // Highlight selected column's header with green
5.     if (DataCol = 12) then
6.       if Column.Field.AsString = 'x' then
7.       (sender as TDBGrid).Canvas.Brush.Color := clGreen;
8. end;
9.  

Now i am putting it in my original database and now i get this stupid error.
And the error doesn't point to my unit/form that i am using but to a helping unit

[madref]

Even stanger....
I deleted my Lib-directory, recompiled everything and now its working

[Handoko]

Glad to hear your issue has been solved.

Me too ever had problems that the code didn't work as it should be, simply deleting the lib folder and recompiling solved it.

[madref]

I have put this back to [Unsolved] because i want to know if it is also possible to give colors to individual ROWS in a DBGrid?

[Handoko]

I haven't tested it on TDBGrid, but int TStringGrid it is possible:

Code: Pascal  [Select][+][-]

1. procedure TMainForm.StringGrid1PrepareCanvas(sender: TObject; aCol,
2.   aRow: Integer; aState: TGridDrawState);
3. begin
4.   if not(Sender = StringGrid1) then Exit;
5.   if (aRow = 2) then StringGrid1.Canvas.Brush.Color := clYellow;
6. end;

[madref]

Yes but DBGrid has no aRow.

Code: Pascal  [Select][+][-]

1. procedure TForm_Wedstrijden_Overzicht.DBGrid_WedstrijdenPrepareCanvas(
2.   sender: TObject; DataCol: Integer; Column: TColumn; AState: TGridDrawState);

[paweld]

Code: Pascal  [Select][+][-]

1. procedure TForm_Wedstrijden_Overzicht.DBGrid_WedstrijdenPrepareCanvas(
2.   sender: TObject; DataCol: Integer; Column: TColumn; AState: TGridDrawState);
3. begin
4.   //For every third row
5.   if (Sender as TDBGrid).Datasource.Dataset.RecNo mod 3=0 then
6.   (Sender as TDBGrid).Canvas.Brush.Color:=clYellow;
7.   //When 'x' value in 5 data field
8.   if (Sender as TDBGrid).Datasource.Dataset.Fields[5].AsString='x' then
9.   begin
10.     (Sender as TDBGrid).Canvas.Font.Style:=[fsBold];
11.     (Sender as TDBGrid).Canvas.Brush.Color:=clGreen;
12.   end;
13. end;
14.  

[madref]

But what if i want to have 3 rows of white and then 3 rows of yellow and then 3 rows of white, etc, etc?

[wp]

Hey come on. Use your brain! Look at paweld's solution. Suppose you have a series of number 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, ... Which math operation is needed to group these numbers by 3?

[madref]

Yes but my brains are not working properly to get a solution 


My brains knows the solution but i can't program it
it something like this
if mod 3 = 0 then change colour overtime