设置绘图区背景颜色

Question

看来$graph->SetColor('red'); doesnt't做任何事情（从jpgraph的的example0.html：

<?php // content="text/plain; charset=utf-8" 
require_once ('jpgraph/jpgraph.php'); 
require_once ('jpgraph/jpgraph_line.php'); 

// Some data 
$ydata = array(11,3,8,12,5,1,9,13,5,7); 

// Create the graph. These two calls are always required 
$graph = new Graph(350,250); 
$graph->SetScale('textlin'); 
$graph->SetColor('red'); #  <---- this does nothing 
// Create the linear plot 
$lineplot=new LinePlot($ydata); 
$lineplot->SetColor('blue'); 

// Add the plot to the graph 
$graph->Add($lineplot); 

// Display the graph 

$graph->Stroke(); 
?> 

我缺少什么

Answer 1

我发现我需要取消激活轴网格的显示，似乎优先于背景颜色设置。添加$graph->ygrid->Show(false, false);后颜色设置工作。