That's not possible in current PrimeFaces 3.x version. It's only possible when you use mode="advanced"
instead of mode="simple"
.
As to your attempt to use the label
attribute, this attribute is only used as label in validation error messages associated with the input component. With your label="Browse"
attempt, in case of a required="true"
validation error, the message would appear like so "Browse is required" instead of "formId:inputId is required".
Update: since PrimeFaces 5.x, you can add skinSimple="true"
to give mode="simple"
the desired skin/look'n'feel as the remainder. Also, the label
will actually be used as button label. See also the showcase.
<p:fileUpload label="Browse" ... mode="simple" skinSimple="true" />