Linking array and drawgrid

Can anyone tell me how to create an array of 10,10 integers in a separate class.  Fill this array with zeroes (0) and ones (1) alternately.  Putting a drawgrid on my form and have depending on the value in my array (in separate class) a circle with different colour (drawcell) in the cell of the drawgrid.

Thank you.
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denizcanConnect With a Mentor Commented:
There is two way of doing it...

One is using a array to mask...
 MyMask: array[1..10, 1..10] of Boolean;

  initiallly all values are False. To do this:
FillChar(MyMask, SizeOf(MyMask), 0);

  than you should set the value of MyMask[ACol, ARow] True when OnMouseClick accours; And Invalidate the DrawGrid to force it repaint.

Now in the DrawCell method, change this line:
  if (ACol > 0) and (ARow > 0) then
  if (ACol > 0) and (ARow > 0) and MyMask[ACol, ARow] then

The second way is to use a buffer array:

MyBuffer: array[1..10, 1..10] of Integer;

FillChar(MyBuffer, SizeOf(MyBuffer),$FF);

You should set the value of MyBuffer[ACol, ARow] to the original value MyArray[ACol, ARow], then Invalidate the grid..

That's all...

pmelkebekeAuthor Commented:
I'm a newbie, please be understanding with my problem.
You necessarily need to define a class for the array?  Or can you use it as a global variable, or as a member of your Form class?

To declare an array:

  MyArray: array[1..10, 1..10] of integer;

To fill the array:

var x :boolean;  i,j :integer;

x := false;
i := 1;
while (i<=10) do begin
  j := 1;
  while (j <=10) do begin
    MyArray[i,j] := ord(x);
    x := not x;
    j := j + 1;
  i := i + 1;

To do it in a separate class is not something a newbie should try to conquer...

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pmelkebekeAuthor Commented:
Ok the array is filled now, Thanks for that.  But ho do I link this to my drawgrid so I can view different colors depending on the values in the array.  Let's say if it's a 0 then make it a blue circle, if it's a 1 make it a red circle.
pmelkebekeAuthor Commented:
To be correct the array makes a part of a class.
for I := 1 to 10 do
  for J := 1 to 10 do
    MyArray[I, J] := (I + J) and 1;

seems smarter...

pmelkebeke, do you want to create a component that screens this array, or just want to show that array...

The former needs complicated steps, but letter is easy...

for letter:
I think you know how DrawGrids works. You should use it's DrawCell event to draw something. Double click, OnDrawCell event, and write a code stg like that:

procedure TForm1.DrawGrid1DrawCell(Sender: TObject; ACol, ARow: Integer;
  Rect: TRect; State: TGridDrawState);
  if (ACol > 0) and (ARow > 0) then
    with TDrawGrid(Sender) do
      case MyArray[ACol, ARow] of
        0: Canvas.Brush.Color := clRed;
        1: Canvas.Brush.Color := clBlue;
        else Canvas.Brush.Color := MyDefaultColor;
      Canvas.Ellipse(Rect.Left, Rect.Top, Rect.Left + 10, Rect.Top + 10);

Here you can fill the array not only 0 and 1's, but also other numbers, and set the color of brush with these numbers...
pmelkebekeAuthor Commented:
So far so good.  Now the following is what I really want:

I have a main form (frmMain) with a drawgrid on it.  I have a unit with my classes in there (uClasses).  In this unit I have a class (Bord) that has an array in it of integers (10,10).  On initialization (Bord.Init) of the Bord-class the array needs to be filled with the zeroes and ones.  On clicking a button on the form the Drawgrid needs to be filled with the colored dots looking at the values of the array in my Bord-class to determine the color.  If 0 then red, if 1 then blue, anything else should be blank.

pmelkebekeAuthor Commented:
Thanks alot you've been a great help!
not at all...
take care...
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