Okay, I think I've figured out a solution. Since the other form inputs must be submitted and validated via Ajax, you can include them in the form and submit them with an Ajax
commandButton. Once the Ajax request is complete, you can execute some JavaScript to click on a hidden
Export button to cause the data to be exported. That way the user only needs to click once to submit info and export data (although those actions will actually occur across two requests).
example.xhtml:<h:form enctype="multipart/form-data">
<h:panelGroup id="inputs">
<p:inputText id="input" value="#{bean.inputValue}" required="true" />
<p:message for="input" />
</h:panelGroup>
<p:commandButton value="Submit + Export"
actionListener="#{bean.clickExportButtonAfterAjaxRequest}" update="inputs" process="inputs @this" />
<p:commandButton id="hiddenNonAjaxExportButton" value="hiddenNonAjaxExportButton" ajax="false"
style="display: none;">
<p:dataExporter fileName="data" target="dataTable" type="csv" />
</p:commandButton>
<p:dataTable id="dataTable" value="#{bean.data}" var="dataRow">
<!-- ... your dataTable code here ... -->
</p:dataTable>
<!-- ... your code here ... -->
</h:form>Bean.java:@ManagedBean(name = "bean")
@RequestScoped
public class Bean {
public void clickExportButtonAfterAjaxRequest(ActionEvent actionEvent) {
RequestContext requestContext = RequestContext.getCurrentInstance();
UIComponent component = actionEvent.getComponent();
UIComponent hiddenNonAjaxExportButton = component.findComponent("hiddenNonAjaxExportButton");
String hiddenNonAjaxExportButtonClientId = hiddenNonAjaxExportButton.getClientId();
requestContext.execute("document.getElementById('" + hiddenNonAjaxExportButtonClientId + "').click();");
}
// ... your code here ...
}On the user's side all that they see is that they've clicked a button to submit the form and export the data (seemingly in 1 action or request), but in reality, the form was submitted and validated in an Ajax request and the data was exported in a non-Ajax request. This ensures that the data is never exported until the form inputs are valid. Then the data is exported because the
Export button is clicked via JavaScript. Note that validation and model value updates will occur twice for the inputs---once for the Ajax request and once for the non-Ajax export request. You might be able to skip the first or second model value update (since the same value will be submitted in the non-Ajax export request) using
FacesContext.renderResponse(), but I couldn't find an easy way to do that. Other than that duplicate update, I think this is the simplest possible way to validate/submit data and export data on the same button press with
p:dataExporter. Note that validation must be performed on both the Ajax and non-Ajax export requests since a hacker could potentially click the hidden export button without clicking the Ajax one (thus submitting invalid data or bypassing validation completely if validation is disabled).
- Kyle
