向ArrayList添加的字符串未显示/未更新[重复]

Question

...所以我有了@ApplicationScoped Bean“应用程序”：

    @ManagedBean(name = "Application")
    @ApplicationScoped
    public class Application implements Serializable {

        private boolean isRunning = false;

        private ArrayList<Feed> sentNotifications = new ArrayList<>();

        private ArrayList<String> emails = new ArrayList<>(
                Arrays.asList("[e-mail]", "[e-mail]")
        );

        private LinkedList<String> words = new LinkedList<>(
                Arrays.asList("vuln","banana","pizza","bonanza")
        );

        private LinkedList<String> feeds = new LinkedList<>(
                Arrays.asList("http://www.kb.cert.org/vulfeed",
                "https://ics-cert.us-cert.gov/advisories/advisories.xml",
                "https://ics-cert.us-cert.gov/alerts/alerts.xml")
        );

...并想添加一个字符串到ArrayList

public String addEmail(String email) {
        emails.add(email);
        return null;
}

Facelet如下所示：

 <!-- EMAILS -->
    <h3>Configured Emails</h3>
    <h:form>
        <h:inputText value="Email" var="email"/>
        <h:commandButton value="Add Email" action="#{Application.addEmail(email)}"/>
    </h:form>
    <h:form>
        <ui:repeat var="email" value="#{Application.emails}">
            <tr>
                <td>#{email}</td>

                <td>
                    <f:facet name="header">Action</f:facet>
                    <h:commandLink value="Delete" action="#{Application.rmEmail(email)}"/>
                </td>
            </tr>
            <br></br>
        </ui:repeat>
    </h:form>

...所以当我尝试添加“[e-mail]“，这是结果：

• 有一个删除按钮显示，但不是字符串本身

请帮忙！谢谢

Answer 1

我终于修好了！

感谢用户@Kukeltje，他暗示我犯了一些基本的错误——以及用户@Wietlol，他通过道德支持和“相信我”在聊天中激励了我：）

解决方案：

…在应用中。爪哇：

public List<Feed> sentNotifications = new ArrayList<>();

public List<String> emails = new ArrayList<>();

public List<String> words = new LinkedList<>(Arrays.asList("vuln", "banana", "pizza", "bonanza"));

public List<String> feeds = new LinkedList<>(
        Arrays.asList("http://www.kb.cert.org/vulfeed",
                "https://ics-cert.us-cert.gov/advisories/advisories.xml",
                "https://ics-cert.us-cert.gov/alerts/alerts.xml")
);

private String currentEmail;
private String currentFeed;
private String currentWord;

[...]

 public void addEmail() {
        emails.add(currentEmail);
 }

…和gui。XHTML：

 <!-- EMAILS -->
    <h3>Configured Emails</h3>
    <h:form>
        <h:inputText value="#{Application.currentEmail}" var="email"/>
        <h:commandButton value="Add Email" action="#{Application.addEmail}"/>
    </h:form>
    <h:form>
        <ui:repeat var="email" value="#{Application.emails}">
            <tr>
                <td>#{email}</td>

                <td>
                    <f:facet name="header">Action</f:facet>
                    <h:commandLink value="Delete" action="#{Application.rmEmail(email)}"/>
                </td>
            </tr>
            <br></br>
        </ui:repeat>
    </h:form>

请注意action=“#{Application.addEmail}”如何不使用参数，而是通过value=“#{Application.currentmail}”将参数传递给方法。

如果你，读者，有同样的问题，请考虑以下几点：

• bean中每个字段的getter/setter

希望这个答案对有同样问题的ppl有用！

你好，格乌尔