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如何将工作命令链接作为子链接添加到组件

custom-component jsf-2 jsf ajax

Marcin Tomiak · 技术社区 · 13 年前

我在应用程序中实现了以下自定义组件:

@FacesComponent ("org.app.component.hintBubble")
public class TutorialHintBubbleComponent extends UIComponentBase implements Serializable {

private static final long serialVersionUID = -8124906197708898894L;

public static final String COMPONENT_TYPE = "org.app.component.hintBubble";

@Override
public String getFamily() {
    return COMPONENT_TYPE;
}

@Override
public boolean isTransient() {
    return false;
}

@Override
public void encodeBegin(FacesContext context) throws IOException {
    setId("hintBubble");

    TutorialHintBubble value = (TutorialHintBubble) this.getValueExpression("value").getValue(context.getELContext());
    ResponseWriter writer = context.getResponseWriter();
    writer.startElement("div", this);
        writer.writeAttribute("style", value.getCss().getBodyCss(), null);
        writer.writeAttribute("class", "hint-bubble", null);

        if ( value.getPointer().getLocation() != HintBubblePoinerLocation.NONE ) {
            writer.startElement("div", this);
                writer.writeAttribute("style", value.getCss().getPointerCss(), null);
                writer.writeAttribute("class", "hint-bubble-pointer", null);
            writer.endElement("div");

            if ( value.getBorder().getThicknessInPixels() > 0 ) {
                writer.startElement("div", this);
                    writer.writeAttribute("style", value.getCss().getPointerBorderCss(), null);
                    writer.writeAttribute("class", "hint-bubble-pointer-border", null);
                writer.endElement("div");
            }
        }



        writer.startElement("div", this);
            writer.writeAttribute("class", "hint-bubble-inner-html-container", null);
            writer.write(value.getInnerHtml());
        writer.endElement("div");

        if ( value.isShowConfirmButton() ) {
            writer.startElement("div", this);
            writer.writeAttribute("class", "hint-bubble-btn-container", null);

            UICommandLink commandLink = new UICommandLink();
            getChildren().add(commandLink);
            commandLink.setParent(this);

            commandLink.setValue(value.getButtonCaption());
            commandLink.setStyleClass("hint-bubble-btn");
            commandLink.setId("okButton");

            ValueExpression actionListenerExpression = getValueExpression("actionListener");

            if ( actionListenerExpression != null ) {
                commandLink.addActionListener(
                    (ActionListener) actionListenerExpression.getValue(context.getELContext())
                );
            }
        }
    }


@Override
public void encodeEnd(FacesContext context) throws IOException {
    ResponseWriter writer = context.getResponseWriter();
    TutorialHintBubble value = (TutorialHintBubble) this.getValueExpression("value").getValue(context.getELContext());
    if ( value.isShowConfirmButton() ) {
        writer.endElement("div");
    }

    writer.endElement("div");
}

}

正如您所看到的,UICommandLink作为子组件添加到该组件中。附加到此命令链接的是ActionListener。ActionListener是根据作为参数传递给HintBubble组件的表达式进行计算的。调试表明操作侦听器已正确评估并添加到UICommandLink中。

xhtml中的代码:

<h:form id="tutorialForm">
<a4j:outputPanel id="tutorialContainer" layout="block" >
    <a4j:repeat value="#{tutorialBean.hintBubbles}" var="hintBubble">
        <gg:hintBubble value="#{hintBubble}" actionListener="#{tutorialManager}" />
    </a4j:repeat>
</a4j:outputPanel>
</h:form>

所有内容都在网页上正确呈现,但当我点击按钮时,不会执行操作。(尽管ajax请求被发送到服务器)

我的问题是:

我应该用哪种方法将UICommandLink添加到组件的子级,以便使事情正常工作?(请注意,UICommandLink来自richfaces,即org.richfaces.component.UICommandLink)

1 回复 | 直到 13 年前

Marcin Tomiak 13 年前

我终于把这件事做好了。我所讨论的JSF组件应该有三个类:组件、呈现器和组件处理程序。

应将子UICommandLink添加到HintBubbleComponent的ComponentHandler中创建的组件的方法中:

public class HintBubbleHandler extends ComponentHandler {

public HintBubbleHandler(ComponentConfig config) {
    super(config);
}

@Override
public void onComponentCreated(FaceletContext ctx, UIComponent c, UIComponent parent) {
    HintBubbleComponent hintBubbleComponent = (HintBubbleComponent) c;

    UICommandLink commandLink = new UICommandLink();
    hintBubbleComponent.getChildren().add(commandLink);
    commandLink.setParent(hintBubbleComponent);
    commandLink.setId("okButton");      
}

}

正因为如此,当回调访问树以查找执行操作的组件时,UICommandLink将出现在组件树中。

在渲染器的decode()方法中,actionListener应设置为UICommandLink:

@Override
public void decode(FacesContext context, UIComponent component) {
    super.decode(context, component);

    UICommandLink commandLink = (UICommandLink) component.getChildren().get(0);

    MethodExpression actionListener =  ((HintBubbleComponent) component).getActionListener();

    if ( actionListener != null ) {
        commandLink.setActionExpression(actionListener);
    }

}

现在一切都在工作,动作被调用了!