当使用 JSF 单击按钮时，我可以显示错误/信息消息，但在加载页面时无法显示消息。
请尝试以下操作。
索引.xhtml：
<!DOCTYPE html>
<html xmlns="http://www.w3.org/1999/xhtml"
xmlns:h="http://xmlns.jcp.org/jsf/html">
<h:head>
<title>Facelet Title</title>
</h:head>
<h:body>
<h:form id="componentForm">
<h:messages errorStyle="color: red" infoStyle="color: green" globalOnly="true" />
Enter the word Java here:
<h:inputText id="javaText" value="#{messageController.javaText}" />
<h:message for="javaText" errorStyle="color: red" infoStyle="color: green" />
<h:commandButton id="addMessage" action="#{messageController.newMessage}"
value="New Message" />
</h:form>
</h:body>
</html>
消息控制器.java：
@Named(value = "messageController")
@SessionScoped
public class MessageController implements Serializable {
int hitCounter = 0;
private String javaText;
public MessageController() {
javaText = null;
FacesMessage facesMsg = new FacesMessage(FacesMessage.SEVERITY_INFO, "Managed Bean Initialized", null);
FacesContext.getCurrentInstance().addMessage(null, facesMsg);
}
public void newMessage() {
String hitMessage = null;
hitCounter++;
if (hitCounter > 1) {
hitMessage = hitCounter + " times";
} else {
hitMessage = hitCounter + " time";
}
Date currDate = new Date();
FacesMessage facesMsg = new FacesMessage(FacesMessage.SEVERITY_ERROR, "You've pressed that button " + hitMessage + "! The current date and time: " + currDate, null);
FacesContext.getCurrentInstance().addMessage(null, facesMsg);
if (getJavaText().equalsIgnoreCase("java")) {
FacesMessage javaTextMsg = new
FacesMessage(FacesMessage.SEVERITY_INFO, "Good Job, that is the correct text!", null);
FacesContext.getCurrentInstance()
.addMessage("componentForm:javaText", javaTextMsg);
} else {
FacesMessage javaTextMsg = new
FacesMessage(FacesMessage.SEVERITY_ERROR, "Sorry, that is NOT the correct text!", null);
FacesContext.getCurrentInstance()
.addMessage("componentForm:javaText", javaTextMsg);
}
}
public String getJavaText() {
return javaText;
}
public void setJavaText(String javaText) {
this.javaText = javaText;
}
}
除构造函数创建的一条消息外，每条消息都正确显示。
我想在加载页面时Managed Bean Initialized显示消息。
我遇到了同样的问题，不幸的是，FacesContext 仅在页面加载时初始化。
所以你不能在页面初始化时使用 FacesContext.getCurrentInstance((.addMessage(( :(
我尝试了2种解决方案
-
文档准备就绪后，调用 ajax 以显示消息
-
传递字符串消息并显示它