[Trinidad] clearing 'inputFile' after PPR request

[Zarick Lau]

Dear Users and Developers,

I've used tr:inputFile with PPR with success, however, after PPR
request is completed, the HTML form still leave the last file path
in the <input type="file" /> control.

When user finally submit the form, the backing bean will
get another file, which are actually processed in last PPR request.

I've tried the following code:

        public void onNewFileChange(ValueChangeEvent event) {
                UploadedFile file = (UploadedFile) event.getNewValue();
                log.debug("onNewFileChange: " + file);
                if (file != null && file.getLength() > 0) {
                        setNewFile(file);
                }
                ((CoreInputFile)event.getComponent()).setValue(null);
                ((CoreInputFile)event.getComponent()).setLocalValueSet(true);
        }

But this doesn't work as expected.
How can I reset that input box?

Best regards,
Zarick Lau