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Nesting and Extending Definitions
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Nesting Definitions
Sometimes it is useful to have a structured page with, say, a structured body.
Tipically, there is a main layout (for example, the "classic" layout) and the
body is made of certain number of sections. In this case, nesting a definition
(the one for the body) inside another definition (the main layout) can be
useful.
* {Named subdefinitions}
Tiles supports nesting definitions natively. One way of usng nested definitions
is creating a named "subdefinition" and using it as an attribute. For example:
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The <<>> definition will be put inside the
<<>>, by putting it inside its <<>> attribute. You will
be seeing the definition one inside the other.
* {Anonymous nested definitions}
What you can do with named subdefinitions can be done with nested anonymous
definitions. The above example can be rewritten in:
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The anonymous definition put under the "body" attribute can be used only by
the surrounding definition. Moreover, you can nest a definition into a nested
definition, with the desired level of depth.
* {Cascaded attributes}
Attributes defined into a definition can be cascaded to be available to all
nested definitions and templates. For example the
{{{#Named_subdefinitions}sample definition}} detailed above can be rewritten
this way:
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The template of <<>> definitionhas been used as the
<<>> attribute in the <<>> definition. All of the
attributes of <<>> has been then moved as attributes
of <<>> definition, but with the addition of the "cascade"
flag.
Extending Definitions
You can extend definitions like a Java class. The concepts of , and are available.
* <>: it is a definition in which the template attributes
are not completely filled. They are useful to create a base page and a number
of extending definitions, reusing already created layout. For example:
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* <>: a definition can inherit from another definition,
to reuse an already made (abstract or not) definition:
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In this case, the <<>>, <<