Seaside - What's the point of implementing #children in a WAComponent when a direct call to "html render:" is made in "renderContentOn: html"?

Question

Whatever >> children
        ^Array with: oneComponent with: anotherComponent.

Later in the code one might have something like this.

Whatever >> renderContentOn: html
        ...
        html render: oneComponent.
        ...
        html render: anotherComponent.

Since I make a call explicitly to render these components, what's the use of having them in #children? Is #children used for anything else?

Answer 1

Seaside depends on #children being correctly implemented for the following callbacks:

• #updateRoot: to customise the head section of the generated HTML document,
• #initialRequest: to initialise the component at the beginning of a session,
• #updateUrl: to modify the current URL,
• #updateStates: to registers objects for backtracking,
• as well as to support helper methods like #states, #scripts, and #styles.

Search the Seaside Book for these methods to learn more about them.