我是Spring Boot和Thymeleaf的新手，想将Java代码中定义的变量的值传递给超文本标记语言页面。我在网上搜索，但可能，我已经监督了一些重要的东西。我尝试使用以下代码：
Favorite.java：
@Getter
@Setter
public class Favorite {
private String id;
private String target;
public Favorite(final String id, final String target) {
setId(id);
setTarget(this.target);
}
}
PortalController.java：
public class PortalController {
private final List<Favorite> myFavorites = new ArrayList<>();
@ModelAttribute("myFavorites")
public List<Favorite> myFavorites() {
if (myFavorites.size() == 0) {
myFavorites.add(new Favorite("ZEMPLOYEE_WORKTIME_ZWD_ESS_ABW", "ABC"));
myFavorites.add(new Favorite("ZEMPLOYEE_WORKTIME_CATS", "DEF"));
myFavorites.add(new Favorite("ZEMPLOYEE_WORKTIME_PEP_WISH_PLAN", "XYZ"));
}
return myFavorites;
}
index. html：
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" xmlns:th="http://www.thymeleaf.org" lang="de" xml:lang="de">
<head>
[…]
</head>
<body>
[…]
<ul>
<div th:switch="${not #lists.isEmpty(myFavorites)}">
<div th:case="true">
<div th:each="myFavorite : ${myFavorites}">
<li>
<td th:text="${myFavorite.id}"></td>
<td th:text="${myFavorite.task}"></td>
</li>
</div>
</div>
<div th:case="*">
Nothing to show!
</div>
</div>
</ul>
[…]
我得到了“没有要显示的！”文本，这意味着myFavorites为空。我错过了什么或者我对此有什么误解？
编辑：
我在深入阅读了The@Model属性后修改了PortalController：
public class PortalController {
private final List<Favorite> myFavorites = new ArrayList<>();
private final Map<String, List<Favorite>> favoritesMap = new HashMap<>();
@RequestMapping(value = "/getMyFavorites", method = RequestMethod.POST)
public String submit(@ModelAttribute("myFavorites") final List<Favorite> favorites,
final BindingResult result, final ModelMap model) {
if (result.hasErrors()) return "error";
model.addAttribute("myFavorites", favorites);
favoritesMap.put(favorites.toString(), favorites);
return "favoritesView";
}
@ModelAttribute
public void getMyFavorites(final Model model) {
if (myFavorites.size() == 0) {
myFavorites.add(new Favorite("ZEMPLOYEE_WORKTIME_ZWD_ESS_ABW", "ABC"));
[…]
}
model.addAttribute("myFavorites", myFavorites);
}
不幸的是，我仍然缺少或误解了一些东西，因此网页仍然返回“无显示！”。
编辑2：
这是我在阅读此处请求的留档后的当前状态：
PortalController.java：
public class PortalController {
private final List<Favorite> myFavorites = new ArrayList<>();
@RequestMapping(value = "/getMyFavorites", method = RequestMethod.GET)
public String submit(@ModelAttribute("myFavorite") final List<Favorite> favorites,
final BindingResult result, final ModelMap model) {
if (result.hasErrors()) return "error";
model.addAttribute("myFavorites", favorites);
return "favoritesView";
}
@ModelAttribute
public void getMyFavorites(final Model model) {
if (myFavorites.size() == 0) {
myFavorites.add(new Favorite("ZEMPLOYEE_WORKTIME_ZWD_ESS_ABW", "ABC"));
[…]
}
model.addAttribute("myFavorites", myFavorites);
}
index. html：
<ul>
<div th:switch="${not #lists.isEmpty(myFavorite)}">
<div th:case="true">
<div th:each="myFavorite : ${myFavorites}">
<li>
<td th:text="${myFavorite.id}"></td>
<td th:text="${myFavorite.task}"></td>
</li>
</div>
</div>
<div th:case="false">
Nothing to show!
</div>
</ul>
但我仍然得到“没什么可展示的！”，因为${myFavorites}是空的。
根据留档，@Model属性应该与@Request estMaps一起使用。您可以在此处找到有关此注释如何工作的更详细描述。
同样为了显示表格，您可以将thymeleaf代码更改为：
<table>
<thead>
<tr>
<th> id</th>
<th> target</th>
</tr>
</thead>
<tbody>
<tr th:if="${myFavorites.empty}">
<td colspan="2"> No Info </td>
</tr>
<tr th:each="myFavorite: ${myFavorites}">
<td><span th:text="${myFavorite.id}"> ID</span></td>
<td><span th:text="${myFavorite.target}"> Target</span></td>
</tr>
</tbody>
</table>
