java - Richface 组件的延迟加载

Question

我正在尝试“延迟加载”richface 组件。不知何故，如果不刷新页面，我就无法渲染它。我想避免整个页面刷新。

情况:

基本页面加载:

menuBean.java

private MenuBarComponent getLazyMenuBarComponent() {
    if (lazyMenuBar != null) {
        return lazyMenuBar;
    }
    lazyMenuBar = new MainMenuBarLazy(); // no children
    return lazyMenuBar;
}

按下“激活菜单”按钮后:

page.xhtml

<a4j:region id="main-menu-region">
    <h:form  id="mainMenu-form">
        <rich:dropDownMenu  binding="#{menuBarBean.menuBar}" 
                        id="HOOFDMENU" 
                        showEvent="mouseup" 
                        onclick="showMenu();" 
                        styleClass="menu-hdr-btn"
                        hideDelay="3600000"
                        showDelay="0"
                        onshow="onMenuShow();" 
        />
        <a4j:jsFunction name="fetchMenu" action="#{menuBarBean.fetchMenu}"
            render="@region @form HOOFDMENU">       <!-- I THOUGHT THIS SHOULD WORK -->
        </a4j:jsFunction>
    </h:form> 
</a4j:region>

<a4j:jsFunction name="fetchMenu" action="#{menuBarBean.fetchMenu}">
</a4j:jsFunction>

<javascript>
  function displayMenu(){
      #{rich:component('HOOFDMENU')}.show();
  }
</javascript>

menuBean.java

public String fetchMenu() {
        if(currentMenuBar.getChildrenSize() > 1){
            return "";
        }
        showMenuBar = true;
        currentMenuBar = getMenuBarComponent();   // The component gets pointed to the full menu
        return "TRUE";// "RELOAD" triggers a full page refresh and shows the full menu;
    }

public UIComponent getMenuBar() {
    if (currentMenuBar == null) {
        currentMenuBar = getLazyMenuBarComponent();
    }
    menuBarComponent = currentMenuBar.build();  // Here the component gets builded. It is chosen to build it in the getter because in the build there is also a check of the users ROLE, which can be changed on the fly.
    return menuBarComponent;
}

编辑后添加

javascript.js

function showMenu(){ // gets triggered when pressed on the dropdown component
    fetchMenu();     // triggers the build-full-menu action
    displayMenu();   // sets dropdownbox to show (the menu should show now), I only get the borders of an empty list
}

如果我在按下菜单激活按钮后按 F5，则会显示完整菜单。如果我返回 fetchMenu() return="RELOAD"页面将重新加载，并且会显示完整菜单。如果我尝试重新渲染区域/表单或在 HOOFDMENU 上，我不会得到任何重新渲染的完整菜单。

如何仅重新加载页面的菜单部分而不重新加载整个页面？

Answer 1

渲染很可能在操作完成之前发生。使用 @oncomplete 调用另一个执行渲染的 jsFunction。即

<a4j:jsFunction name="fetch" oncomplete="reload()" />
<a4j:jsFunction name="reload" render="…" />

另一方面:fetchmenu 函数定义了两次，我没有看到它在任何地方被调用。

getter 中不应该有任何业务逻辑，为什么不在 fetchMenu() 方法中调用 build() 呢？

我不确定您想对“@region @form .HOOFDMENU”做什么，菜单位于该区域内的表单内。 “HOOFDMENU”前面的点可能也不应该在那里。