JSF-关于UIComponent的操作的两个问题 [英] JSF - Two Questions about actions on UIComponent

问题描述

所以，让我向我展示我的麻烦:)

So, let me show us my troubles :)

1-当我单击命令按钮时

<h:commandButton value="Somethings">
    <f:setPropertyActionListener target="#{bean.method}" value="some" />
    <f:ajax render="rendering"/>
</h:commandButton>

我没有对commandButton进行任何操作.我只是开ajax电话.如果我在按钮上添加一个动作(如action="bean.myAction)，它将在JSF生命周期的5度阶段执行(好的，只有当我在f:ajax中写入event ="action"时，这才是默认值).正确的?但是默认情况下，通过点击按钮会触发f:ajax吗?因为例如对于一个ListBox，它仅在我编写event ="change"时才被触发(同样，我不应该编写它，因为它是默认设置).

I dont do any action to the commandButton. Just i fire the ajax call. If i add an action on the button (like action="bean.myAction) it will be executedat the 5° phase of the JSF lifecycle (allright, only if i write event="action" in the f:ajax, but thats as default). Right? But the f:ajax is fired by cliccing on the button as default? Because for a ListBox for example, it's fired only if i write event="change" (the same, i shouldnt write it, because is as default).

2-当我点击图片

<h:graphicImage value="img/img.png" alt="img">
    <f:setPropertyActionListener target="#{bean.method}" value="some" />
    <f:ajax event="onclick" render="rendering"/>
</h:graphicImage>

这不起作用.为什么?

与往常一样，谢谢您的帮助！！！

As usual, thanks for the help!!!!

推荐答案

1-当我单击命令按钮时

我对命令按钮不执行任何操作.我只是开ajax电话.如果我在按钮上添加一个动作(例如action ="bean.myAction)，它将在JSF生命周期的5°阶段执行

I dont do any action to the commandButton. Just i fire the ajax call. If i add an action on the button (like action="bean.myAction) it will be executedat the 5° phase of the JSF lifecycle

f:setPropertyActionListener 也将在第5阶段执行.

The f:setPropertyActionListener will be executed in the 5th phase as well.

(好的，只有当我在f:ajax中写入event ="action"时，这才是默认设置).正确的?但是默认情况下，通过点击按钮会触发f:ajax吗?因为例如对于一个ListBox，它仅在我编写event ="change"时才被触发(同样，我不应该编写它，因为它是默认设置).

(allright, only if i write event="action" in the f:ajax, but thats as default). Right? But the f:ajax is fired by cliccing on the button as default? Because for a ListBox for example, it's fired only if i write event="change" (the same, i shouldnt write it, because is as default).

f:ajax 只是将行为从同步提交更改为异步(部分)提交.通过为父组件的所需事件属性生成一些其他JavaScript代码(例如onclick，onchange等，在webbrowser中查看生成的HTML输出)来完成此操作.它在JSF生命周期中没有任何改变.只有呈现的响应才是部分响应，它恰好是要在具有render属性中定义的ID的组件中进行更新的部分.

The f:ajax just changes the behaviour from a synchronous submit to asynchronous (partial) submit. It does that by generating some additional JavaScript code to the desired event attribute of the parent component (e.g. onclick, onchange, etc, look in generated HTML output in webbrowser). It doesn't change anything in the JSF lifecycle. Only the rendered response will be a partial response which is exactly the part which is to be updated in the component(s) with ID as definied in render attribute.

2-当我点击图片

这不起作用.为什么?

因为 h:graphicImage 完全不支持f:setPropertyActionListener.它仅在 UICommand 组件中有效.

Because the h:graphicImage does not support f:setPropertyActionListener at all. It only works in UICommand components.

您想将其包装在h:commandLink中.

<h:commandLink>
    <f:setPropertyActionListener target="#{bean.method}" value="some" />
    <f:ajax event="action" render="rendering"/>
    <h:graphicImage value="img/img.png" alt="img"/>
</h:commandLink>

(以及必要时将CSS生成的<a>元素引起的边框/下划线样式设置为CSS)

(and if necessary style the border/underline caused by generated <a> element away with CSS)

这篇关于JSF-关于UIComponent的操作的两个问题的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！