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Delphi paintbox

Hi guys

I'm making a line graph application using delphi. I draw a line and ellipse in the paintbox. My question is how can i identify if the mouse over is in the ellipse. I want to show a hint and the text is not fix. Meaning every ellipse has a different hint text. I place the record in a list. So it would be best if an id would also included in the ellipse. Is this possible?

Hope you guys get it.

kretzschmar

maybe

instead of drawing place TShapes

just as an idea

meikl ;-)

tirbanqs

ASKER

nice idea.
is it ok if i have plenty of tshapes. i have plenty of ellipse on the chart.

mokule

Normally You could do it like this

var
h: hrgn;
begin
h := CreateEllipticRgn(10,10,50,50);
if PtInRegion(h,mouse.CursorPos.x,mouse.CursorPos.Y) then
begin
...
end;
DeleteObject(h);

tirbanqs

ASKER

But how can i add an id or any identification on it?
The hint text are on the list.

btw, how can i add your in the paintbox...

mokule

You should have a list ellipsis coordinates and their identifiers.

This code can be in OnMouseMove event.

tirbanqs

ASKER

Can you give me an example.
I'm new to this programming stuff.
I really don't know how to implement your code... sorry

tirbanqs

ASKER

I'll revise my question so it will be easier to understand.

how can i identify that the mouse cursor is over the ellipse? and how can i put an id or identification for each ellipse? because each ellipse hint has different values/text.

help!!! :)

ASKER CERTIFIED SOLUTION

mokule

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tirbanqs

ASKER

Thank you mokule and meikl.

tirbanqs

ASKER

Btw mokule, is it advisable to dispose the pointer when destroying the list? or when freeing the list, is the memory allocated freed?

mokule

You're right. You should dispose pointers before list free.
The correct way is:

procedure TForm1.FormDestroy(Sender: TObject);
var
i: integer;
begin
for i := 0 to List.Count-1 do
Dispose(List.Items[i]);
List.Free;
end;

tirbanqs

ASKER

Thank you mokule.
I implemented your code in my program. It works perfectly.
Thanks again.