public class SimpleType
extends java.lang.Object

An atomic type such as a string or number, that is generally stored, displayed and manipulated as a single value.

This class is not meant to be created and used, it is actually documentation of settings allowed in a DataSource descriptor (.ds.xml file), for use with Smart GWT Pro Edition and above. See com.smartgwt.client.docs.serverds for how to use this documentation.

SimpleTypes can be created at any time, and subsequently referred to as a field type in DataSources and DataBoundComponents. This allows you to define validation, formatting and editing behaviors for a type to be reused across all DataBoundComponents.

The SimpleType class also allows data to be stored in some opaque format but treated as simple atomic values as far as Smart GWT components are concerned by implementing getAtomicValue() and updateAtomicValue() methods. For example, if some record has a field value set to a javascript object with the following properties:

  { stringValue:"A String", length: 9 }
  

this value could be treated as a simple string by defining a SimpleType with inheritsFrom set to "text" and a custom getAtomicValue() method that simply extracted the "stringValue" attribute from the data object. DataBoundComponents would then display the string value, and use it for sorting and other standard databinding features.

Note that the term "simpleType" is used in the same sense as in http://www.w3.org/TR/xmlschema-0/, and XMLTools.loadXMLSchema() will create new SimpleType definitions.

When using the Smart GWT Server, SimpleTypes can be defined server-side, and should be defined server-side if validators are going to be declared so that the server will enforce validation. To define server-side SimpleTypes using Component XML you should create file {typeName}.type.xml in the following format:

    <SimpleType name="{typeName}" inheritsFrom="{otherSimpleType}" 
                   editorType="{FormItemClassName}">
      <validators>
        <!-- validator definition just like DataSourceField -->
      </validators>
    </SimpleType>
  

.. and place this file alongside your DataSource files (.ds.xml) files - in any of folders listed in project.datasources property in server.properties.

SimpleTypes can be loaded via DataSourceLoader or loadDS JSP tags and should be loaded before the definitions of any DataSources that use them (so generally put all SimpleType definitions first).

Define validators in the server-side type definition, for example:

    <SimpleType name="countryCodeType" inheritsFrom="text">
      <validators>
        <validator type="lengthRange" min="2" max="2"
          errorMessage="Length of country code should be equal to 2." />
        <validator type="regexp" expression="[A-Z][A-Z]"
          errorMessage="CountryCode should have only uppercase letters." />
      </validators>
    </SimpleType>
  

For client-side formatters, add these to the type definition after loading it from the server, for example:

      SimpleType.getType("independenceDateType").setShortDisplayFormatter(new SimpleTypeFormatter() {
        public String format(Object value, DataClass field, DataBoundComponent component, Record record) {
          if (value == null) return null;
          return "<i>" + (((java.util.Date) value).getYear() + 1900) + "</i>";
        }
      });
    

Note that formatters must be added to the SimpleType definition before any DataBoundComponent binds to a DataSource that uses the SimpleType.

An example is here.