Android Hello World app fails to build even after adding `android.useAndroidX=true`

[haluzpav]

What version of gRPC-Java are you using?

1.69.0

What is your environment?

MacOS Sequoia 15.0.1
javac 23.0.1
Android Studio Ladybug Feature Drop | 2024.2.2

What did you expect to see?

Working hello world project on Android

What did you see instead?

Building client app fails with

> Task :app:dexBuilderDebug FAILED
ERROR:/Users/haluzpav/git/grpc-java/examples/android/helloworld/app/build/intermediates/javac/debug/classes/io/grpc/helloworldexample/HelloworldActivity$1.class: D8: java.lang.NullPointerException: Cannot invoke "String.length()" because "<parameter1>" is null
ERROR:/Users/haluzpav/git/grpc-java/examples/android/helloworld/app/build/intermediates/javac/debug/classes/io/grpc/examples/helloworld/GreeterGrpc$GreeterStub.class: D8: java.lang.NullPointerException: Cannot invoke "String.length()" because "<parameter1>" is null
ERROR:/Users/haluzpav/git/grpc-java/examples/android/helloworld/app/build/intermediates/javac/debug/classes/io/grpc/helloworldexample/HelloworldActivity$GrpcTask.class: D8: java.lang.NullPointerException: Cannot invoke "String.length()" because "<parameter1>" is null

Full log: error.log

Steps to reproduce the bug

1. https://grpc.io/docs/platforms/android/java/quickstart/#run-the-example
2. Which fails, as described in Android Hello World app requires android.useAndroidX=true #11835
3. Add android.useAndroidX=true into .../helloworld/gradle.properties, as described in the error of the linked issue
4. Get another error, see above

[shivaspeaks]

Potential issue could be build tool incompatibility arising from Android Studio (Ladybug Feature Drop 2024.2.2). Did you try this with lower versions of grpc-java? If not, I'd suggest you to do so and narrow down the root cause.

[haluzpav]

I'm no longer interested. I successfully integrated gRPC into my Android project, with help of various other sources.

I suggest maintainers of this repo just recreate this hello word sample app from scratch, using the latest Android app template in Android Studio, as this current one is outdated basically in all aspects. Easier than trying to debug this IMHO.

[zbjlu]

I also encountered this problem， feel that this problem occurs frequently and is a must-have problem.

[NaveenPrasannaV]

Hi @haluzpav, I’m also facing this same issue with the Android Hello World example. You mentioned you got it working using other sources, can you please share how you fixed it? That would really help me.

[haluzpav]

@NaveenPrasannaV I can't tell anymore, but here's what I added to my project setup when I was integrating gRPC. It's possibly outdated, or dependent on other things I already had in the project. Hope it helps.

Root build.gradle.kts:

plugins {
    // ...
    id("com.google.protobuf") version "0.9.4" apply false
}

app/build.gradle.kts:

val protobufVersion = "4.29.3"
val grpcVersion = "1.69.0"
val grpcKotlinVersion = "1.4.1"

plugins {
    // ...
    id("com.google.protobuf")
}

protobuf {
    protoc {
        artifact = "com.google.protobuf:protoc:$protobufVersion"
    }
    plugins {
        create("grpc") {
            artifact = "io.grpc:protoc-gen-grpc-java:$grpcVersion"
        }
        create("grpckt") {
            artifact = "io.grpc:protoc-gen-grpc-kotlin:$grpcKotlinVersion:jdk8@jar"
        }
    }
    generateProtoTasks {
        all().forEach { task ->
            task.builtins {
                create("java") {
                    option("lite")
                }
                create("kotlin") {
                    option("lite")
                }
            }
            task.plugins {
                create("grpc") {
                    option("lite")
                }
                create("grpckt") {
                    option("lite")
                }
            }
        }
    }
}

dependencies {
    implementation("io.grpc:grpc-okhttp:$grpcVersion")
    implementation("io.grpc:grpc-protobuf-lite:$grpcVersion")
    implementation("com.google.protobuf:protobuf-kotlin-lite:$protobufVersion")
    implementation("io.grpc:grpc-stub:$grpcVersion")
    implementation("io.grpc:grpc-kotlin-stub:$grpcKotlinVersion")
    compileOnly("org.apache.tomcat:annotations-api:6.0.53") // needed for some code generated by Protobuf
}