[Lazarus] Hint as text over TAChart
"Leonardo M. Ramé"
l.rame at griensu.com
Sun Sep 21 13:59:40 CEST 2014
On 21/09/14 07:25, Werner Pamler wrote:
> The most general way: Use the CurrentExtent of the chart, it is in
> "graph coorinates", though, and you have to convert it to pixels yourself:
> procedure TForm1.Button1Click(Sender: TObject);
> ext: TDoubleRect;
> ext := Chart1.CurrentExtent;
> Label1.Caption := Format('Left = %d, Top = %d, Right = %d, Bottom =
> %d', [
> Chart1.XGraphToImage(ext.a.x), // "a" is the lower left corner
> Chart1.YGraphToImage(ext.b.y), // "b" is the upper right corner
> Or you could catch one of the events OnBeforeDrawBackwall or
> OnAfterDrawBackwall which are fired during the painting process and
> contain the rectangle enclosed by the axis lines as a parameter; simply
> store that Rect for later usage.
Great!, I used the onAfterDrawBackwll's rect.
Leonardo M. Ramé
More information about the Lazarus