Manipulating tablePane columns programmatically

The general approach is:

1. XData to ZEN objects
2. Modify object(s)
3. Serialize back into XData.

Sample code (SAMPLES namespace):

/// This is the Desktop Demonstration page for the Zen demonstration application.
Class ZENDemo.AutoDemo Extends %ZEN.Component.page
{

/// Class name of application this page belongs to.
Parameter APPLICATION = "ZENDemo.Application";


/// This XML block defines the contents of this page.
XData Contents [ XMLNamespace = "http://www.intersystems.com/zen" ]
{
<page xmlns="http://www.intersystems.com/zen" title="Zen Desktop Demo">
<tablePane sql="SELECT ID,Name FROM Sample.Person WHERE Name %STARTSWITH ? ORDER BY Name">
<column colName="ID" hidden="0"/>
<column colName="Name"/>
<parameter value="Z"/>
</tablePane>
</page>
}

/// Toggles visibility of the ID column.
/// w $System.Status.GetErrorText(##class(ZENDemo.AutoDemo).Modify())
ClassMethod Modify() As %Status
{
    #Dim pSC As %Status = $$$OK
    #Dim tPage As %ZEN.Component.page
    #Dim tHidden As %Boolean
    Set tSC = ..GetPageObject(, .tPage)
    Quit:$$$ISERR(tSC) tSC

    Set tHidden = tPage.children.GetAt(1).columns.GetAt(1).hidden

    Write "Old ID column hidden value: ", tHidden, !

    Set tPage.children.GetAt(1).columns.GetAt(1).hidden = 'tHidden

    Write "New ID column hidden value: ", 'tHidden, !

    Set tNewStream = ##class(%Stream.TmpCharacter).%New()
    Set tSC = ##class(%ZEN.Utils).%ObjectToXML(tNewStream, tPage)

    Write "New XData: ", 'tHidden, !
    Do tNewStream.Rewind()
    Do tNewStream.OutputToDevice()
    Do tNewStream.Rewind()

    Set tSC = ..SavePage(,tNewStream)

    Do $system.OBJ.Compile($classname())

    Quit tSC
}

ClassMethod GetPageObject(pClassName = {$classname()}, Output pPage As %ZEN.Component.page) As %Status
{
    Set tReader = ##class(%XML.Reader).%New()
    Set tSC = tReader.OpenStream(##class(%Dictionary.CompiledXData).%OpenId(pClassName _ "||" _ "Contents").Data)
    If $$$ISERR(tSC) Quit tSC

    Do tReader.Correlate("page","%ZEN.Component.page")

    #; there should only be one page defined
    Do tReader.Next(.pPage,.tSC)
    Quit:$$$ISERR(tSC) tSC
    Quit:'$IsObject(pPage) $$$ERROR($$$GeneralError,"No <page> element defined in Contents block.")

    Quit tSC
}

ClassMethod SavePage(pClassName = {$classname()}, pStream) As %Status
{
    Set tCDef = ##class(%Dictionary.ClassDefinition).%OpenId(pClassName)
    If '$IsObject(tCDef) {
        Set tSC = $$$ERROR($$$GeneralError,"Unable to open class definition: " _ tClass)
    }
    #; find XDATA Contents block
    Set tIndex = tCDef.XDatas.FindObjectId(pClassName _ "||" _ "Contents")
    If (tIndex '= "") {
        #; get XDATA as stream
        Set tStream = tCDef.XDatas.GetAt(tIndex).Data
        Do tStream.CopyFrom(pStream)
    }
    Else {
        #; create a new XData block !!!
    }
    Set tSC = tCDef.%Save()
    Quit tSC
}

}

Calling:

Write $System.Status.GetErrorText(##class(ZENDemo.AutoDemo).Modify())

Toggles visibility of the ID column.

Hi,

Rather than programmatically modifying the source code and recompiling the class -  if your page already defines, by default, the full set of columns available, you can show and hide each and every one of them programmatically by manipulating the table columns collection which is already part of the DOM:

Save this class in the SAMPLES namespace.  In this example, the Buttons hide some columns and un-hide  others on client and server:

Even if your default <table> definition did not hard-code the full set of columns in the XDATA block, which you later manipulate, you can also programmatically add the table and column objects of the table, something like this - from server side instance method - 

        // Add Table of transactions
        set nTable=##class(%ZEN.Component.tablePane).%New()
        set nTable.id="tblTrans"
        set nTable.queryClass="myAccounts.QryUtils"
        set nTable.queryName="Transaction"

        // Define a column and add to table

        set column=##class(%ZEN.Auxiliary.column).%New() 
        set column.colName="Narrative"
        set column.hidden=1
        do nTable.%AddColumn(column)

        do %page.%AddComponent(nTable)

- Steve