Adding Controls to an AccessControl

by Claudio Mascioni

Category: User Interface

Problem

You have to add controls as ChooseListControl, RadioButtonsControl, ButtonControl, to an AccessControl to increase choice of operator. A TimeStamp autogenerated Key.

Ingredients

- RecordControl

- AccessControl

- ChooseListControl to select a table to open, and to select the index order

IMPORTANT: In this example, the tables must have all the same structure because changing the table is not handled by AccessControl

- RadioButtonsControl to select an ascending or descendig sort order

Recipe

"layout()" is used to pass the parameter "query" to the AccessControl.

Controller
    {
    Title: "find item"
    New()
        {
        super(.layout())
        .sortIndex = 'NOINDEX'
        .sortOrder = ''
        }
    layout()
       {

In the variable "query" is stored the table name to open the first time when opening the Access window. The first time the table does not have a sort order.

        query =  .FirstTime()
        return Object('RecordControl'
            Object('Vert'
                Object('Horz'
                    Object('Static' 'selected table: ')
                    Object('ChooseList' name: 'Chlt', listField: 'cm_tables', selectFirst:)
                    Object('Skip' 5)
                    Object('Static' 'ordered by: ')
                    Object('ChooseList' name: 'Chls', listField: 'cm_index',   selectFirst:)
                    Object('Skip' 5)
                    Object('Static' 'sort order: ')
                    Object('RadioButtons' "ascending", "descending", name: 'RB1', horz:)
                    Object('Skip' 20)
                    Object('Button' 'press', command:'Pressed')
                    )
                Object('Access' query title: '')
                )
            )
        }
    FirstTime()
       {
       .SetCurrTable('tables')
       return Suneido.cm_temp_currentTable
       }

With Record_NewValue(field,value) we trap when is manually selected a table name, an index, or a sort order from a Control. This code filter that only changed fields with name 'Chlt', 'Chls' and 'RB1' can use the routine. In a program that does not use RecordControl, this action is trapped from NewValue(value,source). Using Record_NewValue(source,value) "source" is RecordControl().

    Record_NewValue(field,value)
        {
        if ((field isnt 'Chlt') and (field isnt 'Chls') and (field isnt 'RB1'))
            return

        // check if .Data is not initialized the first time
        try
            if (.Data is false)
                return 
        catch
            return  

        .SetCurrTable(.Data.GetField('Chlt'))
        .sortIndex = .Data.GetField('Chls').Replace('/' ',')
        if (field is 'RB1')
            {
            if (value is 'ascending')
                .sortOrder = ''
            else
                .sortOrder = 'reverse '
            }
       .qry = Suneido.cm_temp_currentTable
       if (.sortIndex isnt 'NOINDEX') 
            .qry $= ' sort ' $ .sortOrder $ .sortIndex
       .Data.Vert.Access.ChangeQuery(.qry)
       }

The Suneido global object is used to store the current table value because this value will be used from Rule_cm_index to return a list of available index for the selected table.

    SetCurrTable(tablename)
       {
       Suneido.cm_temp_currentTable = tablename
       }

To trap the Button "press" action. Used only for an example.

    On_Pressed()
        {
        Alert('Do something', 'Do something', flags: MB.ICONINFORMATION)
        }

To trap the close window action of the operator and give him an alert:

    Ok_to_CloseWindow?()
        {
        if (not OkCancel("sure to exit?"))
            return false  
        else
            return true  // destroy the window
        }
}

To trap the close window action to delete "cm_temp_currentTable" from the Suneido global object before exiting the program:

    Destroy()
        {
        Suneido.Delete('cm_temp_currentTable')
        super.Destroy()
        }

This "Rule" return a list of tables. This list is used to populate a ChooseListControl to can select a table to open. This list tables must have all the same structure(and different data) In this example it return only the Suneido table "tables".

Rule_cm_tables
function ()
    {
    return "tables"
    // example   return "table_x, table_y, table_z"   all with the same structure
    }

This "Rule" return a list of all keys and indexes that have the selected table. This list is used to populate a ChooseListControl to can select and index to order the records displayed in the AccessControl window. The Replace(',' '/') is used in case of index composed with more than one field. The "NOINDEX" indicate that there is not a sort order.

Rule_cm_index
function ()
    {
    result = "NOINDEX"
    query = "tables where tablename = '" $ Suneido.cm_temp_currentTable $
        "' join indexes"
    QueryApply(query)
        { |x|
        idx = x.columns.Replace(',' '/')
        result $= ', ' $ idx
        }
    return result
    }

Notes:

To use a TimeStamp autogenerated to set the Key inserting a new record.

For example, we suppose that the name of the field Key to autogenerate is "id_xyz".

We need to define the key Field and an associated Rule. They must have the same name with the difference that begin with "Field_" and "Rule_" prefix.

Field_id_xyz
Field_string
    {
    Prompt: 'record ID'
    Control: (Field, width: 20)
    Format: (Text, width: 20)
    }

Rule_id_xyz
function()
    {
    return Timestamp()
    }

When inserting the new record, automatically the key field "id_xyz" is set to the value returned from the Rule_id_xyz function.

If you want that the operator does not modify the key value, you have to change, in the layout() part, this code.

Object('Access' query title: '')

with this:

Object('Access' query title: '', protectField: 'protectRule')

and add this Rule:

Rule_protectRule
function()
    {
    return #(cm_id_xyz:, allowDelete:)
    }

You can use whatever rule name you want; Rule_protectRule is an example. If you want that the operator does not delete records, you have to simply remove the word allowDelete: from the Rule_protectRule.