Changing API

Let us extend the API with more functionality: we want to let clients specify a list of lines for the birthday card:

package com.example.birthdayservice;
/** Birthday service interface. */
interface IBirthdayService {
    /** Generate a Happy Birthday message. */
    String wishHappyBirthday(String name, int years, in String[] text);
}

This results in an updated trait definition for IBirthdayService:

trait IBirthdayService {
    fn wishHappyBirthday(
        &self,
        name: &str,
        years: i32,
        text: &[String],
    ) -> binder::Result<String>;
}

• Note how the String[] in the AIDL definition is translated as a &[String] in Rust, i.e. that idiomatic Rust types are used in the generated bindings wherever possible:
  • in array arguments are translated to slices.
  • out and inout args are translated to &mut Vec<T>.
  • Return values are translated to returning a Vec<T>.