帶有呈現屬性的jsf commandlink和commandbutton不會觸發actionlistener

Question

我正在使用primefaces在頁面上顯示一些數據，並且在CLOB類型數據上單擊時我想打開一個彈出窗口（使用primefaces對話框組件）來顯示完整數據。問題是，當我把呈現的atrribute放到commandlink時，它不會觸發backing bean上的方法。如果我不使用渲染的atrribute，它會正確地啓動該方法。但它不會正確傳遞參數。

backing bean是viewscoped。我提交時可能是關於bean的狀態是否丟失？如果是這樣，那麼要做什麼來克服呢？

這裏是源：

<p:dataTable id="dynamicDBReaderResultTable" 
    widgetVar="wv_dynamicDBReaderResult" paginator="true" page="1" 
    rows="10" value="#{controller.data}" var="record" 
    paginatorTemplate="{FirstPageLink} {PreviousPageLink} {PageLinks} {NextPageLink} {LastPageLink} {RowsPerPageDropdown}" 
    rowsPerPageTemplate="10,25,50,100" 
    emptyMessage="#{dtsmsgm['NoRecords']}" 
    errorMessage="Error viewing data" rowIndexVar="rownumber" lazy="false" 
    dynamic="true"> 
    <p:column> 
     <h:outputText value="#{rownumber+1}" 
      style="font-weight:bold; font-size:1.05em" /> 
    </p:column> 
    <p:columns value="#{controller.columnNames}" var="columnName" 
     columnIndexVar="columnIndex"> 
     <f:facet name="header"> 
      <h:outputText value="#{columnName}" /> 
     </f:facet> 
     <h:outputText value="#{record[columnIndex].toDisplayString()}" /> 

<p:commandLink id="showDataButton" value="..." 
      actionListener="#{controller.prepareLargeData(rownumber,columnIndex)}" 
      rendered="#{record[columnIndex].dataType eq '2005'}" //if this attribute is removed, it fires the action, but with both parameters as zero 
      onsuccess="dlg.show()"> 
     </p:commandLink> 



    </p:columns> 
</p:dataTable> 

<p:dialog id="largeDataDialog" header="Large Data Content" 
    widgetVar="dlg" closeOnEscape="true" minHeight="150"> 
    <h:outputText id="largeData" value="#{controller.largeData}" /> 
</p:dialog> 

輔助Bean：

@ManagedBean(name = "dynamicDBReader") 
@ViewScoped 
public class DynamicDBReader extends AEntityBean<AEntity> { 
private List<String> columnNames; 
private List<DBData[]> tabularData; 
private boolean showTable; 
private DBData largeData; 


public void prepareLargeData(int rowNumber, int columnIndex) { 
    largeData = tabularData.get(rowNumber)[columnIndex]; 
} 

@Override 
public void init() { 
    reInit(); 
} 

private void reInit() { 
    columnNames = new ArrayList<String>(); 
    tabularData = new ArrayList<DBData[]>(); 
    selectedRelease = getLastRelease(); 
    setShowTable(false); 
} 



public List<DBData[]> getData() { 
    return tabularData; 
} 

public List<String> getColumnNames() { 
    return columnNames; 
} 


/** 
* @param showTable 
*   the showTable to set 
*/ 
public void setShowTable(boolean showTable) { 
    this.showTable = showTable; 
} 

/** 
* @return the showTable 
*/ 
public boolean isShowTable() { 
    return showTable; 
} 

/** 
* @param largeData 
*   the largeData to set 
*/ 
public void setLargeData(DBData largeData) { 
    this.largeData = largeData; 
} 

/** 
* @return the largeData 
* @throws SQLException 
* @throws IOException 
*/ 
public String getLargeData() { 
    if (largeData == null) { 
     return ""; 
    } 
    try { 
     return largeData.toFullString(); 
    } catch (IOException ioe) { 
     String errorMessage = "Failed reading data"; 
     LogUtil.error(logger, errorMessage, ioe); 
    } catch (SQLException sqle) { 
     String errorMessage = "Failed reading data"; 
     LogUtil.error(logger, errorMessage, sqle); 
    } 
    return ""; 
} 

} 

Answer 1

如果變量columIndex的值的形式提交的HTTP POST請求期間已改變，可以發生。如果#{controller.columnNames}依賴於基於請求的條件，而該條件僅在使用表格顯示頁面時纔是正確的，則會發生這種情況。您需要確保您在視圖範圍的bean的（後）構造函數中預初始化它，並且該值不會在getter方法中初始化/操作。