Java 如何使弹簧复选框默认选中？
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How to make spring checkboxes checked by default?
提问by Dave
I'm using Spring 3.1.0.RELEASE. I have this field in my command object ...
我正在使用 Spring 3.1.0.RELEASE。我的命令对象中有这个字段......
public Set<EventFeed> getUserEventFeeds() {
return this.userEventFeeds;
}
On my Spring JSP page, I want to display a checkbox list of all possible event feeds, and then have checked checkboxes if the user has one in his set. I want to have some special HTML formatting around each checkbox, so I'm trying ...
在我的 Spring JSP 页面上，我想显示所有可能的事件提要的复选框列表，然后如果用户在他的集合中有复选框，则选中复选框。我想在每个复选框周围设置一些特殊的 HTML 格式，所以我正在尝试......
<form:form method="Post" action="eventfeeds.jsp" commandName="user">
...
<c:forEach var="eventFeed" items="${eventFeeds}">
<tr>
<td><form:checkbox path="userEventFeeds" value="${eventFeed}"/></td>
<td>${eventFeed.title}</td>
</tr>
</c:forEach>
...
However, the items aren't getting checked by default if one is in the set. How do I do this? Here is the binder I'm using in my controller class ...
但是，如果项目在集合中，则默认情况下不会检查项目。我该怎么做呢？这是我在控制器类中使用的活页夹...
@InitBinder
public void initBinder(WebDataBinder binder) {
binder.registerCustomEditor(EventFeed.class, new EventFeedEditor());
}
private class EventFeedEditor extends PropertyEditorSupport {
@Override
public void setAsText(String text) throws IllegalArgumentException {
setValue(eventFeedsDao.findById(Integer.valueOf(text)));
}
@Override
public String getAsText() {
return ((EventFeed) getValue()).getId().toString();
}
}
采纳答案by raddykrish
@Dave, there is something called form:checkBoxes. You can try with that.
@Dave，有一种叫做 form:checkBoxes 的东西。你可以试试。
<form:checkboxes path="userEventFeeds" items="${eventFeeds}" itemLabel="id" itemValue="value"/>
My assumption here is you should have "id" and "value" defined in the EventFeed class.
我的假设是您应该在 EventFeed 类中定义“id”和“value”。
I just tried this by having a String[] availableList and String[] selectedList. It works like charm. You can give a try as well.
我只是通过使用 String[] availableList 和 String[] selectedList 来尝试这个。它就像魅力一样。你也可以试试。
回答by Jhonathan
You can do this by placing selected default property true in your class
您可以通过在您的班级中放置选定的默认属性 true 来做到这一点
class User {
boolean userEventFeeds = true;
}
回答by Andrea
I've tried both form:checkboxesand form:checkboxwith the same data and the first works, the second doesn't. (Same release of Spring you have)
我都试过form:checkboxes，并form:checkbox使用相同的数据和第一部作品，第二个没有。（与您拥有的 Spring 版本相同）
It looks like there was a bugwhich, despite their claim, seems to be still there.
看起来有一个错误，尽管他们声称，但似乎仍然存在。
回答by keaplogik
Interestingly this works:
有趣的是，这有效：
<form:checkbox path="services" value="${type}" checked="checked"/>
回答by Angelo Fuchs
For my usecase (reacting on stuff in a list that has nothing to do with the object being filled), this code worked:
对于我的用例（对列表中与正在填充的对象无关的内容做出反应），此代码有效：
(Please be aware that this is a last-resort kind of code, other solutions are most likely better suited.)
（请注意，这是最后一种代码，其他解决方案很可能更适合。）
<%@ taglib prefix="jstl" uri="http://java.sun.com/jsp/jstl/core" %>
<jstl:forEach var="listObject" items="${someList}">
<jstl:if test="${listObject.active}">
<form:checkbox path="active" checked="checked"/>
</jstl:if>
<jstl:if test="${!listObject.active}">
<form:checkbox path="active"/>
</jstl:if>
</jstl:forEach>
