In this example you will be modifying the Marital Status drop-down list found on the Contacts form (CR302000):

To add new items to the PXStringListAttribute successor

The best way to extend drop-down items hard-coded inside an attribute inherited from the PXStringList or PXIntList attribute is by increasing size of the _AllowedValues and _AllowedLabels arrays in the constructor of your custom field attribute:

[PXLocalizable(Messages.Prefix)]
public static class MaritalStatusesMessages
{
    public const string CommonLaw = "Living common law";
    public const string Separated = "Separated (not living common law)";
    public const string DivorcedNoCommonLaw = "Divorced (not living common law)";
    public const string NeverMarried = "Never Married";
}

public class MaritalStatusesCst1Attribute : MaritalStatusesAttribute
{
    public const string CommonLaw = "L";
    public const string Separated = "P";
    public const string NeverMarried = "N";

    public MaritalStatusesCst1Attribute()
    {
        Array.Resize(ref _AllowedValues, _AllowedValues.Length + 3);
        _AllowedValues[_AllowedValues.Length - 3] = CommonLaw;
        _AllowedValues[_AllowedValues.Length - 2] = Separated;
        _AllowedValues[_AllowedValues.Length - 1] = NeverMarried;
        Array.Resize(ref _AllowedLabels, _AllowedLabels.Length + 3);
        _AllowedLabels[_AllowedLabels.Length - 3] = MaritalStatusesMessages.CommonLaw;
        _AllowedLabels[_AllowedLabels.Length - 2] = MaritalStatusesMessages.Separated;
        _AllowedLabels[_AllowedLabels.Length - 1] = MaritalStatusesMessages.NeverMarried;
    }
}

In the sample above, you increased size of the _AllowedValues and _AllowedLabels arrays to add 3 additional items to the Marital Status drop-down list. Internal values, stored in the _AllowedValues array, will be assigned to DAC fields and saved in database, and external values from the _AllowedValues array represent internal values in the UI.

To test the results, in the Contact DAC extension, decorate MaritalStatus field with the MaritalStatusesCst1Attribute:

public class ContactExt : PXCacheExtension<Contact>
{
    [PXRemoveBaseAttribute(typeof(MaritalStatusesAttribute))]
    [PXMergeAttributes(Method = MergeMethod.Append)]
    [MaritalStatusesCst1]
    public string MaritalStatus { get; set; }
}

Now there are 7 items in the Marital Status drop-down list:

To remove items declared in the PXStringListAttribute successor

To remove specific drop-down item, that was hard-coded inside an attribute inherited from the PXStringList or PXIntList attribute, you need to decrease size of the _AllowedValues and _AllowedLabels arrays in the constructor of your custom field attribute:

public class MaritalStatusesCst2Attribute : MaritalStatusesCst1Attribute
{
    public MaritalStatusesCst2Attribute()
    {
        string[] allowedValues = new string[_AllowedValues.Length - 1];
        string[] allowedLabels = new string[_AllowedLabels.Length - 1];
        Array.Copy(_AllowedValues, 1, allowedValues, 0, _AllowedValues.Length - 1);
        Array.Copy(_AllowedLabels, 1, allowedLabels, 0, _AllowedValues.Length - 1);
        _AllowedValues = allowedValues;
        _AllowedLabels = allowedLabels;
    }
}

In the sample above, you decreased size of the _AllowedValues and _AllowedLabels arrays to remove Single item from the Marital Status drop-down list.

To test the results, in the Contact DAC extension, decorate MaritalStatus field with the MaritalStatusesCst2Attribute:

public class ContactExt : PXCacheExtension<Contact>
{
    [PXRemoveBaseAttribute(typeof(MaritalStatusesAttribute))]
    [PXMergeAttributes(Method = MergeMethod.Append)]
    [MaritalStatusesCst2]
    public string MaritalStatus { get; set; }
}

Now there are only 6 items: 3 original and 3 custom - in the Marital Status drop-down list:

To replace items declared in the PXStringListAttribute successor

To replace specific drop-down item, originally hard-coded inside an attribute inherited from the PXStringList or PXIntList attribute, you need to update appropriate value in the _AllowedValues and _AllowedLabels arrays in the constructor of your custom field attribute:

public class MaritalStatusesCst3Attribute : MaritalStatusesCst2Attribute
{
    public const string DivorcedNoCommonLaw = "V";

    public MaritalStatusesCst3Attribute()
    {
        _AllowedValues[Array.IndexOf(_AllowedValues, Divorced)] = DivorcedNoCommonLaw;
        _AllowedLabels[Array.IndexOf(_AllowedLabels, Messages.Divorced)] = MaritalStatusesMessages.DivorcedNoCommonLaw;
    }
}

In the sample above, you replaced D - Divorced item with V - Divorced (not living common law) in the _AllowedValues and _AllowedLabels arrays respectively. By doing so, we replace both internal and external values of a drop-down item.

To test the results, in the Contact DAC extension, decorate MaritalStatus field with the MaritalStatusesCst3Attribute:

public class ContactExt : PXCacheExtension<Contact>
{
    [PXRemoveBaseAttribute(typeof(MaritalStatusesAttribute))]
    [PXMergeAttributes(Method = MergeMethod.Append)]
    [MaritalStatusesCst3]
    public string MaritalStatus { get; set; }
}

Now there are only 6 items: 2 original, 3 custom and 1 replaced - in the Marital Status drop-down list: