Primefaces selectManyCheckbox

Question

我有selectManyCheckbox，但我无法从更改事件后检查值（选定值列表保持空白）。 更改事件被触发，但在调试模式下，listSelectedSignalCauses中没有值。 我试图设置一些转换器，但它也没有帮助（也许这是错误的转换器）。

<p:selectManyCheckbox value="#{SignalAnalysisBean.listSelectedSignalCauses}" layout="pageDirection" styleClass="lstSignal"> 
    <f:selectItems value="#{SignalAnalysisBean.listSignalCauses}" var="causes" itemValue="#{causes}" itemLabel="#{causes.name}" /> 
    <p:ajax process="@this" update="test" event="change" listener="#{SignalAnalysisBean.checkCausesList}" /> 
        </p:selectManyCheckbox> 
<h:outputText value="#{SignalAnalysisBean.arrSize}" id="test" /> 

public class SignalAnalysisBean extends AbstractBean { 
    private List<GeneralCollDTO> listSignalCauses; 
    private List<GeneralCollDTO> listSelectedSignalCauses; 
    //... 

    public void checkCausesList(){ 
     arrSize = 4 + listSelectedSignalCauses.size(); 
    } 
    //... 
} 

public class GeneralCollDTO { 
    private String name; 
    private String value; 

    public GeneralCollDTO() { } 

    public GeneralCollDTO(String n, String v) { 
     this.name = n; 
     this.value = v; 
    } 

    public String getName() { 
     return name; 
    } 

    public void setName(String name) { 
     this.name = name; 
    } 

    public String getValue() { 
     return value; 
    } 

    public void setValue(String value) { 
     this.value = value; 
    } 
} 

Answer 1

最后我最终得到了适用于我的通用转换器。

@FacesConverter(value = "generalCollDTOConverter", forClass = GeneralCollDTOConverter.class) 
public class GeneralCollDTOConverter implements Converter { 

    private static Map<Object, String> entities = new HashMap<Object, String>(); 

    @Override 
    public String getAsString(FacesContext context, UIComponent component, Object value) { 
    synchronized (entities) { 
     if (!entities.containsKey(value)) { 
      String uuid = UUID.randomUUID().toString(); 
      entities.put(value, uuid); 
      return uuid; 
     } else { 
      return entities.get(value); 
     } 
    } 
    } 

    @Override 
    public Object getAsObject(FacesContext context, UIComponent component, String value) { 
    for (Entry<Object, String> entry : entities.entrySet()) { 
     if (entry.getValue().equals(value)) { 
      System.out.println("getKey:" + entry.getKey()); 
      return entry.getKey(); 
     } 
    } 
    return value; 
    } 
} 

Answer 2

为了一个自定义的对象发送到你需要实现一个转换器的托管bean，否则你将无法做到这一点。下面的代码根据你的代码实现它，它可能是解决问题的办法。

@FacesConverter(value = "generalCollDTOConverter", forClass = GeneralCollDTOConverter.class) 
public class GeneralCollDTOConverter implements Converter { 

    @Override 
    public Object getAsObject(FacesContext ctx, UIComponent component, String value) { 
     if (value != null) { 
      return component.getAttributes().get(value); 
     } 
     return null; 
    } 

    @Override 
    public String getAsString(FacesContext ctx, UIComponent component, Object value) { 
     if (value != null && value instanceof GeneralCollDTO) { 
      GeneralCollDTO generalCollDTO = (GeneralCollDTO) value; 

      if (generalCollDTO.getName() != null) { 
       component.getAttributes().put(generalCollDTO.getName(), value); 
       return generalCollDTO.getName(); 
      } 
     } 
     return null; 
    } 
} 



<p:selectManyCheckbox converter="generalCollDTOConverter" value="#{SignalAnalysisBean.listSelectedSignalCauses}" layout="pageDirection" styleClass="lstSignal">