Interface Localizable

All Known Subinterfaces:
CellTree.CellTreeMessages, Constants, ConstantsWithLookup, CurrencyCodeMapConstants, DateTimeConstantsImpl, Localizable, LocalizableResource, Messages, NumberConstantsImpl, SimplePager.ImageButtonsConstants, TimeZoneConstants

public interface Localizable
A tag interface that serves as the root of a family of types used in static internationalization. Using GWT.create(class) to instantiate a type that directly extends or implements Localizable invites locale-sensitive type substitution.

Locale-sensitive Type Substitution

If a type Type directly extends or implements Localizable (as opposed to Constants or Messages) and the following code is used to create an object from Type as follows:
Type localized = (Type)GWT.create(Type.class);
then localized will be assigned an instance of a localized subclass, selected based on the value of the locale client property. The choice of subclass is determined by the following naming pattern:
If locale is...     The substitute class for Type is...
unspecified Type itself, or Type_ if Type is an interface
x Class Type_x if it exists, otherwise treated as if locale were unspecified
x_Y Class Type_x_Y if it exists, otherwise treated as if locale were x
where in the table above x is a ISO language code and Y is a two-letter ISO country code.

Specifying Locale

The locale of a module is specified using the locale client property, which can be specified using either a meta tag or as part of the query string in the host page's URL. If both are specified, the query string takes precedence.

To specify the locale client property using a meta tag in the host HTML, use gwt:property as follows:

<meta name="gwt:property" content="locale=x_Y">
For example, the following host HTML page sets the locale to "ja_JP":
<html>
  <head>
    <meta name="gwt:module" content="com.google.gwt.examples.i18n.ColorNameLookupExample">
    <meta name="gwt:property" content="locale=ja_JP">
  </head>
  <body>
    <script src="gwt.js"></script>
  </body>
</html>

To specify the locale client property using a query string, specify a value for the name locale. For example,

http://www.example.org/myapp.html?locale=fr_CA

For More Information

See the GWT Developer Guide for an introduction to internationalization.
See Also: