我对Spring和Spring Web Flow很陌生。 我遇到了无法将视图与提交表单绑定的问题： - 以下是我的代码： -
P.s：我不知道模型= {}在流XML中做了什么，但这已经是代码中已有的，并且将其更改为alertForm不会改变行为/
a）JSP
<form:form name="alertSubmitForm" method="post" id="alertsForm" modelAttribute="alertForm">
<table class="general">
<tr>
<th>Alert Text
</th>
<td><form:textarea path="alertText" cols="50" id="alertText" style="padding-top: 11px"></form:textarea>
</td>
<td><span id="characterCount"></span>/250
</td>
<td><br/><br/><br/><br/><br/><input id="advancedAlertOptions" type="button" value="More" class="primarybtn" style="float:right;"/></td>
</tr>
<tr class="advancedAlertOptions" style="display:none">
<th>Active Date
</th>
<td><form:input path="activeDate" id="activeDate" type="date"/>
</td>
</tr>
<tr class="advancedAlertOptions" style="display:none">
<th>Expiration Date
</th>
<td><form:input id="expDate" path="expDate" type="date"/>
</td>
</tr>
<tr class="advancedAlertOptions" style="display:none">
<th>Author
</th>
<td><form:input id="author" path="author" type="text" disabled="true" value="${author}" />
</td>
</tr>
<tr class="advancedAlertOptions" style="display:none">
<th>Added on
</th>
<td><form:input id="addedDate" type="date" path="addedDate" disabled="true"/>
</td>
</tr>
</table>
<input id="cancelAddAlert" type="button" value="Cancel" class="secondarybtn" style="float:right; margin-left:20px;"/>
<input id="persistAlert" type="submit" value="Add" class="secondarybtn" style="float:right;" name="_eventId_addAlert"/>
</form:form>
b）Flow XML
<view-state id="general" view="editMember/general" model="{}" parent="#abstract-member-view">
<on-entry>
<evaluate expression="new com.company.member.alerts.AlertForm()" result="viewScope.alertForm"/>
</on-entry>
<on-render>
<evaluate expression="alertManagementService.getAlertsList(partyIdMember)" result="viewScope.alerts" />
</on-render>
<transition on="addAlert" to="general" bind="true" >
<evaluate expression="alertManagementService.addAlertToMember(alertForm,partyIdMember)" />
</transition>
</view-state>
c）服务电话
package com.company.member.alerts;
import java.text.DateFormat;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Calendar;
import java.util.Date;
import java.util.List;
import org.hibernate.SQLQuery;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;
import com.company.domain.db.GenericDao;
@Service("alertManagementService")
@Transactional(readOnly = true)
public class AlertManagementServiceImpl implements AlertManagementService {
@Autowired
GenericDao dao;
@Override
public List<AlertForm> getAlertsList(Long memberId) {
String a = "SELECT * FROM PARTY_ALERT WHERE PARTY_ID = "+memberId+ " ORDER BY PA_ACTIVE_DATE";
SQLQuery query = dao.createSQLQuery(a);
List<Object[]> queryResults = query.list();
List<AlertForm> results = new ArrayList<AlertForm>();
for(Object[] arr : queryResults) {
AlertForm alertForm = new AlertForm();
DateFormat df = new SimpleDateFormat("yyyy-MM-dd H:m:s");
try {
alertForm.setAlertId(Long.valueOf(arr[0].toString()));
alertForm.setMemberId(Long.valueOf(arr[1].toString()));
alertForm.setAlertText(arr[2].toString());
Date acD = df.parse(arr[3].toString());
alertForm.setActiveDate(acD);
if(arr[4]!=null) {
Date expD = df.parse(arr[4].toString());
alertForm.setExpDate(expD);
}
alertForm.setAuthor(arr[5].toString());
Date adD = df.parse(arr[6].toString());
alertForm.setAddedDate(adD);
alertForm.setAddedDate(adD);
alertForm.setActiveDate(acD);
}
catch (ParseException e) {
e.printStackTrace();
}
results.add(alertForm);
}
return results;
}
@Override
public void addAlertToMember(AlertForm alert, Long memberID) {
Date expDate;
PartyAlerts partyAlertsDB = new PartyAlerts();
if(alert.getAlertText()!=null) {
partyAlertsDB.setAlertText(alert.getAlertText());
partyAlertsDB.setActiveDate(alert.getActiveDate());
partyAlertsDB.setMemberId(memberID);
if((expDate = alert.getExpDate())!=null) {
partyAlertsDB.setInactiveDate(expDate);
}
}
else { //hardcoding into DB
partyAlertsDB.setActiveDate(new Date());
partyAlertsDB.setInactiveDate(new Date());
partyAlertsDB.setAlertText("This is a hardcoded alert");
partyAlertsDB.setMemberId(memberID);
}
dao.save(partyAlertsDB);
}
}
d）Form Backing Bean
package com.company.member.alerts;
import java.io.Serializable;
import java.util.Date;
public class AlertForm implements Serializable{
private static final long serialVersionUID = 1L;
private Long alertId;
private Long memberId;
private String alertText;
private Date activeDate;
private Date expDate;
private Date addedDate;
private String author;
public AlertForm() {
}
public Long getAlertId() {
return alertId;
}
public void setAlertId(Long alertId) {
this.alertId = alertId;
}
public Long getMemberId() {
return memberId;
}
public void setMemberId(Long memberId) {
this.memberId = memberId;
}
public String getAlertText() {
return alertText;
}
public void setAlertText(String alertText) {
this.alertText = alertText;
}
public Date getActiveDate() {
return activeDate;
}
public void setActiveDate(Date activeDate) {
this.activeDate = activeDate;
}
public Date getExpDate() {
return expDate;
}
public void setExpDate(Date expDate) {
this.expDate = expDate;
}
public Date getAddedDate() {
return addedDate;
}
public void setAddedDate(Date addedDate) {
this.addedDate = addedDate;
}
public String getAuthor() {
return author;
}
public void setAuthor(String author) {
this.author = author;
}
}
问题在于 - 当我提交表单时 - alertForm元素为NULL。获取渲染上所有警报的getter按预期工作。
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答案 0 :(得分：0)
如果您不熟悉SWF，为什么要使用流继承等高级功能？包含引用的父流的内容是什么：
... model =“{}”parent =“＃abstract-member-view”＆gt;
这很可能是您问题的根源。您需要将模型属性显式定义为已初始化的POJO，以便将表单字段正确绑定到它。
因此，为了测试目的，简化在流程中初始化一个新的AlertForm，在视图状态之前和之外的某些地方
....
<set name="alertFormModel" value="new com.company.member.alerts.AlertForm()"/>
....
<!-- then when you enter the view-state define it like this: -->
<view-state id="general" view="editMember/general" model="alertFormModel">
....
</view-state>
如果此测试有效，则为AlertForm创建/实现Factory模式，以消除流xml中丑陋的“新”语法