I am currently attempting to invoke a JavaScript script to export a chart from the PrimeFaces chart component. The issue I am facing is that the base64str variable appears to be null, and the script responsible for populating this value is not being called for some unknown reason:
XHTML code :
<p:chart id="chart" type="line" widgetVar="chart" model="#{cont.lineModel}" style="height:550px;width:1800px">
<p:ajax event="itemSelect" listener="#{cont.itemSelect}" update="growl" />
</p:chart>
<p:commandButton id="exp" value="Export" icon="ui-icon-extlink"
onclick="exportChart();" actionListener="#{cont.submittedBase64Str}"
/>
<h:inputHidden id="b64" value="#{cont.base64Str}" />
<script type="text/javascript">
function exportChart() {
img = chart.exportAsImage();
document.getElementById('hform:b64').value = img.src;
}
</script>
Controller :
public void submittedBase64Str(ActionEvent event){
// You probably want to have a more comprehensive check here.
// In this example I only use a simple check
if(base64Str.split(",").length > 1){
String encoded = base64Str.split(",")[1];
byte[] decoded = org.apache.commons.codec.binary.Base64.decodeBase64(encoded);
// Write to a .png file
try {
RenderedImage renderedImage = ImageIO.read(new ByteArrayInputStream(decoded));
ImageIO.write(renderedImage, "png", new File("D:\\out.png"));
} catch (IOException e) {
e.printStackTrace();
}
}
}
Thank you