JSF datatable：添加和删除行清除行值 [英] JSF datatable: adding and removing rows clear rows values
问题描述
我在表之前渲染添加行按钮，和表的每一行上的删除行按钮。
烘焙bean是viewScoped，并且按钮从后台的java列表中添加/删除元素bean，然后返回到相同的视图。
我将button中的immediate属性设置为true，以便在添加或删除时无法验证输入字段一行。
一切正常，但有一件事情：输入文件的值被清除。我认为这个视图保持了值beacuse的bean是viewScoped。
如何实现添加/删除行而不触发验证并保留已经输入的值用户的形式？
我的观点：
< h ：形式>
< h：commandButton value =AñadirFilaimmediate =trueaction =＃{tablaController.addRowAction}/>
< h：dataTable value =＃{tablaController.lista}var =filacellpadding =0cellspacing =0border =1>
< f：facet name =header> TABLA< / f：facet>
< h：column>
< f：facet name =header>< h：outputLabel value =NOMBRE/>< / f：facet>
< h：inputText id =nomvalue =＃{fila.nombre}/>
< h：message for =nomclass =msjError/>
< / h：column>
< h：column>
< f：facet name =header>< / f：facet>
< h：commandButton value =Quitar Filaimmediate =trueaction =＃{tablaController.removeRowAction（fila）}/>
< / h：column>
< / h：dataTable>
< / h：form>
我的支持bean：
@ManagedBean（name =tablaController）
@ViewScoped
public class TablaController {
private List< Fila>清单
...
public TablaController（）{}
...
@PostConstruct
public void init（）{
this.lista = new ArrayList< ; Fila>（）; （int i = 0; i <5; i ++）{
Fila fila = new Fila（）;
fila.setNombre（）;
this.lista.add（我，fila）;
}
}
...
public String addRowAction（）{
Fila fila = new Fila（）;
fila.setNombre（）;
this.lista.add（fila）;
return;
}
public String removeRowAction（Fila f）{
boolean exito = this.lista.remove（f）;
return;
}
...
}
更新 - >我的解决方案：
如果有人感兴趣，我在这里写下我的解决方案。
问题是我使用immediate =true来跳过验证，但这也使得跳过update_model_values，以便用户在窗体中输入的值在点击添加/删除按钮并重新重新打开页面后丢失
当我使用JSR-303 bean验证时，我的解决方案是使用f：validateBean来跳过验证来启用/禁用它们。根据按钮我点击，如果我想要验证执行，我启用bean验证（例如在提交按钮），如果我想跳过它，我禁用bean验证（如在添加/删除行按钮）。但是无论如何，update_model_values总是执行，所以值不会丢失。
这是视图：
< h：form>
< f：validateBean disabled =＃{！empty param ['disableValidation']}>
< h：commandButton value =AñadirFilaaction =＃{tablaController.addRowAction}>
< f：param name =disableValidationvalue =true/>
< / h：commandButton>
< h：dataTable value =＃{tablaController.lista}var =filacellpadding =0cellspacing =0border =1>
< f：facet name =header> TABLA< / f：facet>
< h：column>
< f：facet name =header>< h：outputLabel value =NOMBRE/>< / f：facet>
< h：inputText id =nomvalue =＃{fila.nombre}/>
< h：message for =nomclass =msjError/>
< / h：column>
< h：column>
< f：facet name =header>< / f：facet>
< h：commandButton value =Quitar Filaaction =＃{tablaController.removeRowAction（fila）}>
< f：param name =disableValidationvalue =true/>
< / h：commandButton>
< / h：column>
< / h：dataTable>
< h：commandButton value =Submitaction =＃{tablaController.saveData}/>
< / f：validateBean>
< / h：form>
支持bean：
@ManagedBean（name =tablaController）
@ViewScoped
public class TablaController {
private List< Fila>清单
...
public TablaController（）{}
...
@PostConstruct
public void init（）{
this.lista = new ArrayList< ; Fila>（）; （int i = 0; i <5; i ++）{
Fila fila = new Fila（）;
fila.setNombre（fila+ i）;
this.lista.add（我，fila）;
}
}
...
public String addRowAction（）{
Fila fila = new Fila（）;
fila.setNombre（）;
this.lista.add（fila）;
return;
}
public String removeRowAction（Fila f）{
this.lista.remove（f）;
return;
}
...
public String saveData（）{
...
//处理有效数据
//例如，调用一种将数据存储在数据库中的服务方法
...
return;
}
...
}
我在按钮中将immediate属性设置为true，以便在添加或删除行时无法验证输入字段。
immediate =true是作业的错误工具。应该用于确定优先级，而不是启用/禁用验证。你遇到自己的区别是相当大的。
你想有条件地触发验证。在例如 required =true，这将像
; h：inputText ... required =＃{saveButtonPressed}/>
其中＃{saveButtonPressed} 评估<$当按下保存按钮时，c $ c> true 例如。当客户端ID存在于请求参数映射中时。
在JSR 303 bean验证的情况下，这将是
< f：validateBean disabled =＃{not saveButtonPressed}>
< h：inputText ... />
< / f：validateBean>
或与 OmniFaces < o：validateBean> ，它允许在每个命令的基础上进行控制。
< h：commandButton id =add...>
< o：validateBean disabled =true/>
< / h：commandButton>
I have a h:datatable showing a list of rows, and the fields of each row are input fields.
I render an "Add Row" button before the table, and a "Remove Row" button on each row of the table.
The baking bean is viewScoped, and the buttons add/remove elements from the java list in the backing bean, and then return to the same view.
I set the immediate attribute to "true" in the buttons in order to not validate the input fields when I add or remove a row.
Everything works ok but one thing: the values of the input fileds are cleared. I thought that the view kept the values beacuse the bean is viewScoped.
How can I achieve adding/removing rows without triggering validations and keeping the values that were already typed by the user in the form?
My view:
<h:form>
<h:commandButton value="Añadir Fila" immediate="true" action="#{tablaController.addRowAction}" />
<h:dataTable value="#{tablaController.lista}" var="fila" cellpadding="0" cellspacing="0" border="1">
<f:facet name="header">TABLA</f:facet>
<h:column>
<f:facet name="header"><h:outputLabel value="NOMBRE" /></f:facet>
<h:inputText id="nom" value="#{fila.nombre}" />
<h:message for="nom" class="msjError" />
</h:column>
<h:column>
<f:facet name="header"></f:facet>
<h:commandButton value="Quitar Fila" immediate="true" action="#{tablaController.removeRowAction(fila)}" />
</h:column>
</h:dataTable>
</h:form>
My backing bean:
@ManagedBean(name="tablaController")
@ViewScoped
public class TablaController {
private List<Fila> lista;
...
public TablaController() { }
...
@PostConstruct
public void init() {
this.lista = new ArrayList<Fila>();
for (int i=0; i<5; i++) {
Fila fila = new Fila();
fila.setNombre("");
this.lista.add(i,fila);
}
}
...
public String addRowAction () {
Fila fila = new Fila();
fila.setNombre("");
this.lista.add(fila);
return "";
}
public String removeRowAction (Fila f) {
boolean exito = this.lista.remove(f);
return "";
}
...
}
UPDATE --> MY SOLUTION:
I write here my solution if someone is interested.
The problem is that I use immediate="true" to skip validations, but this makes to skip the update_model_values too, so that the values entered by the user in the form are lost after clicking the add/remove buttons and re-redenring the page.
As I use "JSR-303 bean validation", my solution was to skip validations using the f:validateBean to enable/disable them. Depending on the button I click, if I want the validations to execute, I enable the bean validation (for example in a "submit" button), and if I want to skip them, I disable bean validation (like in the add/remove row buttons). But anyway the update_model_values always executes, so the values are not lost.
Here's the view:
<h:form>
<f:validateBean disabled="#{!empty param['disableValidation']}">
<h:commandButton value="Añadir Fila" action="#{tablaController.addRowAction}">
<f:param name="disableValidation" value="true" />
</h:commandButton>
<h:dataTable value="#{tablaController.lista}" var="fila" cellpadding="0" cellspacing="0" border="1">
<f:facet name="header">TABLA</f:facet>
<h:column>
<f:facet name="header"><h:outputLabel value="NOMBRE" /></f:facet>
<h:inputText id="nom" value="#{fila.nombre}" />
<h:message for="nom" class="msjError" />
</h:column>
<h:column>
<f:facet name="header"></f:facet>
<h:commandButton value="Quitar Fila" action="#{tablaController.removeRowAction(fila)}">
<f:param name="disableValidation" value="true" />
</h:commandButton>
</h:column>
</h:dataTable>
<h:commandButton value="Submit" action="#{tablaController.saveData}" />
</f:validateBean>
</h:form>
The backing bean:
@ManagedBean(name="tablaController")
@ViewScoped
public class TablaController {
private List<Fila> lista;
...
public TablaController() { }
...
@PostConstruct
public void init() {
this.lista = new ArrayList<Fila>();
for (int i=0; i<5; i++) {
Fila fila = new Fila();
fila.setNombre("fila "+i);
this.lista.add(i,fila);
}
}
...
public String addRowAction () {
Fila fila = new Fila();
fila.setNombre("");
this.lista.add(fila);
return "";
}
public String removeRowAction (Fila f) {
this.lista.remove(f);
return "";
}
...
public String saveData () {
...
//processes the valid data
//for example, calls to a service method to store them in a database
...
return "";
}
...
}
I set the immediate attribute to "true" in the buttons in order to not validate the input fields when I add or remove a row.
immediate="true" is the wrong tool for the job. It should be used to prioritize validation, not to enable/disable validation. The difference is rather huge as you encountered yourself.
You want to trigger validation conditionally. In case of e.g. required="true" that'd be as easy as
<h:inputText ... required="#{saveButtonPressed}" />
where #{saveButtonPressed} evaluates true when the save button is pressed. E.g. when its client ID is present in request parameter map.
In case of JSR 303 bean validation, that'd be a matter of
<f:validateBean disabled="#{not saveButtonPressed}">
<h:inputText ... />
</f:validateBean>
or with OmniFaces <o:validateBean> which allows controlling that on a per-command basis.
<h:commandButton id="add" ...>
<o:validateBean disabled="true" />
</h:commandButton>
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