Sending Objects
AIDL objects can be sent either as a concrete AIDL type or as the type-erased
IBinder interface:
birthday_service/aidl/com/example/birthdayservice/IBirthdayInfoProvider.aidl:
package com.example.birthdayservice;
interface IBirthdayInfoProvider {
    String name();
    int years();
}
birthday_service/aidl/com/example/birthdayservice/IBirthdayService.aidl:
import com.example.birthdayservice.IBirthdayInfoProvider;
interface IBirthdayService {
    /** The same thing, but using a binder object. */
    String wishWithProvider(IBirthdayInfoProvider provider);
    /** The same thing, but using `IBinder`. */
    String wishWithErasedProvider(IBinder provider);
}
birthday_service/src/client.rs:
/// Rust struct implementing the `IBirthdayInfoProvider` interface.
struct InfoProvider {
    name: String,
    age: u8,
}
impl binder::Interface for InfoProvider {}
impl IBirthdayInfoProvider for InfoProvider {
    fn name(&self) -> binder::Result<String> {
        Ok(self.name.clone())
    }
    fn years(&self) -> binder::Result<i32> {
        Ok(self.age as i32)
    }
}
fn main() {
    binder::ProcessState::start_thread_pool();
    let service = connect().expect("Failed to connect to BirthdayService");
    // Create a binder object for the `IBirthdayInfoProvider` interface.
    let provider = BnBirthdayInfoProvider::new_binder(
        InfoProvider { name: name.clone(), age: years as u8 },
        BinderFeatures::default(),
    );
    // Send the binder object to the service.
    service.wishWithProvider(&provider)?;
    // Perform the same operation but passing the provider as an `SpIBinder`.
    service.wishWithErasedProvider(&provider.as_binder())?;
}- Note the usage of BnBirthdayInfoProvider. This serves the same purpose asBnBirthdayServicethat we saw previously.