Bonjour,
je voudrais insérer un histogramme dans ma feuille excel. Cependant, lors de l'appel de stroke() j'ai le fameux : "header already send..."

Pouvez vous me dire comment faire?

<?
header("Content-Type: application/vnd.ms-excel");
header('Content-Disposition: attachement; filename="listDispo.xls"');
...

?>
<table border="1">
	<tr>
		<td></td>
		<td></td>
	</tr>
	<tr>
		<td>Nom du collaborateur</td>
		<td>Disponibilité pour le mois <? echo $month;?></td>
	</tr>

....

</table>

<?
include ("src/jpgraph.php");
include ("src/jpgraph_bar.php");

$data1y=array(12,8,19,3,10,5);
$data2y=array(8,2,11,7,14,4);

// Create the graph. These two calls are always required
$graph = new Graph(310,200,"auto");    
$graph->SetScale("textlin");

$graph->SetShadow();
$graph->img->SetMargin(40,30,20,40);

// Create the bar plots
$b1plot = new BarPlot($data1y);
$b1plot->SetFillColor("orange");
$b2plot = new BarPlot($data2y);
$b2plot->SetFillColor("blue");

// Create the grouped bar plot
$gbplot = new AccBarPlot(array($b1plot,$b2plot));

// ...and add it to the graPH
$graph->Add($gbplot);

$graph->title->Set("Accumulated bar plots");
$graph->xaxis->title->Set("X-title");
$graph->yaxis->title->Set("Y-title");

$graph->title->SetFont(FF_FONT1,FS_BOLD);
$graph->yaxis->title->SetFont(FF_FONT1,FS_BOLD);
$graph->xaxis->title->SetFont(FF_FONT1,FS_BOLD);

// Display the graph
$graph->Stroke();
?>

Merci d'avance