Question

我对素数commandButton和fileupload有疑问。用户通过撇号commandButton选择（但未上传）文件时，我需要启用fileupload，但是我不知道如何检测到已选择文件。

我的代码是：

<h:form enctype="multipart/form-data" id="formCrearPanel2">

    <p:panelGrid columns="2" style="width: 100%">

        <h:outputText value="#{messages['listado.LOGO']}" />
        <p:fileUpload id="fileUploadCrear" widgetVar="fileUploadCrearWV" 
            fileUploadListener="#{listadoPlataformas.subidaImagenCrear}" 
            label="#{messages['comun.SELECCIONAR']}" sizeLimit="1048576" fileLimit="1"
            invalidSizeMessage="#{messages['comun.IMAGE.SIZE']}" 
            update="formularioPrincipal:listadoPlataformas formularioPrincipal:growl" 
            fileLimitMessage="#{messages['comun.IMAGE.FILE_LIMIT']}"  previewWidth="160">

        </p:fileUpload>

    </p:panelGrid>
    <p:panelGrid columns="3" style="width:100%; text-align:center;">

        <p:commandButton value="#{messages['comun.ACEPTAR']}"
            id="crearPlataformaAceptar_2" widgetVar="crearPlataformaAceptarWV_2" ajax="true" onclick="PF('fileUploadCrearWV').upload();"
            update="formularioPrincipal:listadoPlataformas formularioPrincipal:growl" 
            actionListener="#{listadoPlataformas.nothing}" disabled="true"/>


    </p:panelGrid>
</h:form>

我用

Primefaces 6.2-JDK 11-JSF 2.2.19

在p：fileupload

0 个答案: