Thyme leaf show selected value from object - spring-boot

Question

I have a Spring Boot 1.3 app using Thymeleaf. I have a screen that shows a list of users, including the institution they are associated with. Thanks to some previous StackOverflow help, I am able to create a new user and select their institution from a drop down list. I am now trying to do something similar for editing a user - when you edit the record, the dropdown defaults to the institution the user has already been assigned.
I have a User:
#Entity
#Table(name = "Users")
public class User implements UserDetails {
#Id
private String username;
...
#ManyToOne(fetch = FetchType.EAGER, cascade = CascadeType.ALL)
#JoinColumn(name = "institutionId", nullable = false)
private Institution institution;
}
And an Institution:
#Entity
#Table(name = "Institution")
public class Institution {
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
private Long institutionId;
private String name;
#OneToMany(mappedBy = "institution", fetch = FetchType.EAGER)
#Fetch(value = FetchMode.SUBSELECT)
List<User> users = new ArrayList<User>();
}
And here is my HTML to edit the user record (edited):
I have attached screen shots showing a user with an assigned institution, but when I try to edit, there is no dropdown.
How do I get that drop down there, and ideally pre-selected with the user.institution?
Here you can see the edit user does not have the dropdown:
EDIT to show progress and clean up the question:
I have it so that the the list appears to show the institution on the user when I go to edit.
<div class="col-md-5">
<div th:if="${user.institution != null }"
<select name="user.institution">
<option th:each="choice : ${institutionList}"
th:value="${choice.institutionId}"
th:attr="choiceinstitutionId=${choice.institutionId}, institutioninstitutionId=*{institution.institutionId}, showselected=(${choice.institutionId} == *{institution.institutionId})"
th:selected="(${choice.institutionId} == *{institution.institutionId})"
th:readonly="(${choice.institutionId} == *{institution.institutionId})"
th:text="${choice.name}">
</option>
</select>
</div>
<div th:if="${user.institution == null }">
<div th:if="${institutionList != null and not #lists.isEmpty(institutionList)}">
<select name="user.institution">
<option th:each="dropDownItem : ${institutionList}"
th:value="${dropDownItem.institutionId}"
th:text="${dropDownItem.name}" />
</select>
</div>
<div th:if="${institutionList == null or #lists.isEmpty(institutionList)}">
<div>"No Institutions were found, please create some first"</div>
</div>
</div>
<div th:if="${institutionList == null or #lists.isEmpty(institutionList)}">
<div>"No Institutions were found, please create some first"</div>
</div>
</div>
This is very close, except that it doesn't actually set the selected dropdown value on the user object, so its set to null each time...

Answer 1

Turns out it was a dumb mistake - not actually declaring the field to set. In case anyone else runs into a similar issue, here is the correct code to display any selected value in the list, and to set it:
<div th:if="${user.institution != null }">
<select name="user.institution" th:field="*{institution}">
<option th:each="choice : ${institutionList}"
th:value="${choice.institutionId}"
th:attr="choiceinstitutionId=${choice.institutionId}, institutioninstitutionId=*{institution.institutionId}, showselected=(${choice.institutionId} == *{institution.institutionId})"
th:selected="(${choice.institutionId} == *{institution.institutionId})"
th:readonly="(${choice.institutionId} == *{institution.institutionId})"
th:text="${choice.name}"></option>
</select>
</div>
<div th:if="${user.institution == null }">
<div th:if="${institutionList != null and not #lists.isEmpty(institutionList)}">
<select name="user.institution" th:field="*{institution}">
<option th:each="dropDownItem : ${institutionList}"
th:value="${dropDownItem.institutionId}"
th:text="${dropDownItem.name}" />
</select>
</div>
<div th:if="${institutionList == null or #lists.isEmpty(institutionList)}">
<div>"No Institutions were found, please create some first"</div>
</div>
</div>