add rust lib support

app/build.gradle

@@ -29,10 +29,14 @@ android {
     kotlinOptions {
         jvmTarget = '1.8'
     }
+    buildFeatures {
+        viewBinding true
+    }
 }
 
 dependencies {
 
+    implementation project(':rsdroid')
     implementation 'androidx.core:core-ktx:1.7.0'
     implementation 'androidx.appcompat:appcompat:1.3.1'
     implementation 'com.google.android.material:material:1.4.0'

app/src/main/java/com/linkedin/android/kotinrustproto/MainActivity.kt

@@ -2,10 +2,26 @@ package com.linkedin.android.kotinrustproto
 
 import androidx.appcompat.app.AppCompatActivity
 import android.os.Bundle
+import android.util.Log
+import android.view.View
+import com.linkedin.android.kotinrustproto.databinding.ActivityMainBinding
+import com.linkedin.android.rsdroid.RustCore
 
 class MainActivity : AppCompatActivity() {
+    private lateinit var binding: ActivityMainBinding
+
     override fun onCreate(savedInstanceState: Bundle?) {
         super.onCreate(savedInstanceState)
-        setContentView(R.layout.activity_main)
+        binding = ActivityMainBinding.inflate(layoutInflater);
+        binding.text.text = RustCore.instance.greeting();
+
+        binding.button.setOnClickListener(View.OnClickListener {
+            RustCore.instance.callback(object : RustCore.Callback {
+                override fun onSuccess() {
+                    binding.text.text = "Changed";
+                }
+            });
+        })
+        setContentView(binding.root);
     }
 }

app/src/main/res/layout/activity_main.xml

@@ -9,10 +9,22 @@
     <TextView
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
+        android:id="@+id/text"
         android:text="Hello World!"
         app:layout_constraintBottom_toBottomOf="parent"
         app:layout_constraintLeft_toLeftOf="parent"
         app:layout_constraintRight_toRightOf="parent"
         app:layout_constraintTop_toTopOf="parent" />
 
+    <Button
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:id="@+id/button"
+        app:layout_constraintTop_toBottomOf="@+id/text"
+        android:text="Callback"
+        app:layout_constraintBottom_toBottomOf="parent"
+        app:layout_constraintLeft_toLeftOf="parent"
+        app:layout_constraintRight_toRightOf="parent"
+        />
+
 </androidx.constraintlayout.widget.ConstraintLayout>

build.gradle

@@ -16,6 +16,7 @@ buildscript {
         classpath 'com.google.protobuf:protobuf-gradle-plugin:0.8.17'
 
         classpath 'gradle.plugin.org.mozilla.rust-android-gradle:plugin:0.9.0'
+        classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:1.5.31"
         // NOTE: Do not place your application dependencies here; they belong
         // in the individual module build.gradle files
     }

rsdroid/.gitignore

@@ -0,0 +1 @@
+/build

rsdroid/build.gradle

@@ -0,0 +1,51 @@
+apply plugin: 'com.android.library'
+apply plugin: 'kotlin-android' // required for aar generation to link to from AnkiDroid
+
+android {
+    compileSdkVersion 30
+    buildToolsVersion "30.0.1"
+    ndkVersion "22.1.7171670" // Used by GitHub actions - avoids an install step on some machines
+
+    compileOptions {
+        sourceCompatibility JavaVersion.VERSION_1_8
+        targetCompatibility JavaVersion.VERSION_1_8
+    }
+
+    defaultConfig {
+        minSdkVersion 21
+        targetSdkVersion 30
+        versionCode 1
+        versionName VERSION_NAME
+
+        consumerProguardFiles "consumer-rules.pro"
+    }
+
+    buildTypes {
+        release {
+            minifyEnabled false
+            proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro'
+        }
+    }
+}
+
+// Consider upgrade to DSL: https://docs.gradle.org/current/userguide/plugins.html#sec:plugins_block
+apply plugin: "org.mozilla.rust-android-gradle.rust-android"
+
+cargo {
+    module = "../rslib-bridge"
+    libname = "rsdroid"
+    targets = ["x86", "arm", "arm64"]
+    profile = 'release'
+    prebuiltToolchains = true
+    apiLevel = 21
+    verbose = true
+}
+
+dependencies {
+    implementation fileTree(dir: "libs", include: ["*.jar", '*.so'])
+    implementation 'androidx.appcompat:appcompat:1.3.1'
+    implementation "androidx.core:core-ktx:+"
+    implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk7:1.5.31"
+}
+
+preBuild.dependsOn "cargoBuild"

rsdroid/gradle.properties

@@ -0,0 +1 @@
+VERSION_NAME=0.1.0

rsdroid/proguard-rules.pro

@@ -0,0 +1,21 @@
+# Add project specific ProGuard rules here.
+# You can control the set of applied configuration files using the
+# proguardFiles setting in build.gradle.
+#
+# For more details, see
+#   http://developer.android.com/guide/developing/tools/proguard.html
+
+# If your project uses WebView with JS, uncomment the following
+# and specify the fully qualified class name to the JavaScript interface
+# class:
+#-keepclassmembers class fqcn.of.javascript.interface.for.webview {
+#   public *;
+#}
+
+# Uncomment this to preserve the line number information for
+# debugging stack traces.
+#-keepattributes SourceFile,LineNumberTable
+
+# If you keep the line number information, uncomment this to
+# hide the original source file name.
+#-renamesourcefileattribute SourceFile

rsdroid/src/main/AndroidManifest.xml

@@ -0,0 +1,5 @@
+<manifest xmlns:android="http://schemas.android.com/apk/res/android"
+    package="com.linkedin.android.rsdroid">
+
+
+</manifest>

rsdroid/src/main/java/com/linkedin/android/rsdroid/RustCore.kt

@@ -0,0 +1,20 @@
+package com.linkedin.android.rsdroid;
+
+class RustCore {
+
+    external fun greeting(): String
+    external fun callback(cb : Callback)
+    init {
+        System.loadLibrary("rsdroid")
+    }
+
+    companion object {
+        val instance: RustCore = RustCore()
+    }
+
+
+    interface Callback {
+        fun onSuccess()
+    }
+
+}

rslib-bridge/.gitignore

@@ -0,0 +1,2 @@
+Cargo.lock
+target/*

rslib-bridge/Cargo.toml

@@ -0,0 +1,18 @@
+# cargo-features = ["strip"]
+
+[package]
+name = "rsdroid"
+version = "0.1.0"
+authors = ["David Allison <[email protected]>"]
+edition = "2018"
+
+[lib]
+crate_type = ["dylib"]
+
+[dependencies]
+jni = { version = "0.17.0", default-features = false }
+# picked bundled - TODO: Is this correct?
+rusqlite = { version = "0.23.1", features = ["trace", "functions", "collation", "bundled"] }
+
+[features]
+no-android = []

rslib-bridge/src/.gitignore

@@ -0,0 +1 @@
+backend_proto.rs

rslib-bridge/src/lib.rs

@@ -0,0 +1,24 @@
+#[macro_use]
+extern crate jni;
+use jni::JNIEnv;
+use jni::objects::{JClass, JString, JObject};
+use jni::sys::{jbyteArray, jint, jlong, jobjectArray, jarray, jstring};
+use std::ffi::CString;
+
+#[no_mangle]
+pub unsafe extern fn Java_com_linkedin_android_rsdroid_RustCore_greeting(env: JNIEnv, _: JClass) -> jstring {
+    let world_ptr = CString::new("Hello world from Rust world").unwrap();
+    let output = env.new_string(world_ptr.to_str().unwrap()).expect("Couldn't create java string!");
+    output.into_inner()
+}
+
+#[no_mangle]
+pub unsafe extern fn Java_com_linkedin_android_rsdroid_RustCore_callback(
+    env: JNIEnv,
+    _class: JClass,
+    callback: JObject,
+) {
+    env.call_method(callback, "onSuccess", "()V", &[])
+        .unwrap();
+}
+

settings.gradle

@@ -7,4 +7,5 @@ dependencyResolutionManagement {
     }
 }
 rootProject.name = "KotinRustProto"
+include ':rsdroid'
 include ':app'