Android example version compatibility

doc/source/changelog.md

@@ -8,6 +8,8 @@
 
 - **Add support for ** `workload_id` **and** `group_id` **in Driver API** ([#1595](https://github.com/adap/flower/pull/1595))
 
+- **Make Android example compatible with** `flwr >= 1.0.0` **and the latest versions of Android** ([#1603](https://github.com/adap/flower/pull/1603))
+
 ### Incompatible changes
 
 ## v1.2.0 (2023-01-13)

examples/android/apk/download_apk.sh

@@ -1 +1 @@
-wget https://www.dropbox.com/s/e14t3e9py3mr73v/flwr_android_client.apk?dl=1
+wget https://www.dropbox.com/s/ii0vwrjrpupifiv/flower-client.apk?dl=0

examples/android/client/.gitignore

@@ -0,0 +1,4 @@
+.gradle
+.idea
+local.properties
+app/src/main/assets

examples/android/client/app/build.gradle

@@ -2,14 +2,13 @@ apply plugin: 'com.google.protobuf'
 apply plugin: 'com.android.application'
 
 android {
-    compileSdkVersion 29
-    buildToolsVersion "29.0.0"
+    compileSdkVersion 33
 
     defaultConfig {
         applicationId "flwr.android_client"
         // API level 14+ is required for TLS since Google Play Services v10.2
         minSdkVersion 24
-        targetSdkVersion 29
+        targetSdkVersion 33
         versionCode 1
         versionName "1.0"
     }
@@ -30,21 +29,24 @@ android {
         enabled = true
     }
 
-    aaptOptions {
-        noCompress "tflite"
-    }
 
-    lintOptions {
+    namespace 'flwr.android_client'
+    androidResources {
+        noCompress 'tflite'
+    }
+    lint {
         disable 'GoogleAppIndexingWarning', 'HardcodedText', 'InvalidPackage'
+        textOutput file('stdout')
         textReport true
-        textOutput "stdout"
     }
 }
 
+def grpc_version = '1.43.0'
+
 protobuf {
     protoc { artifact = 'com.google.protobuf:protoc:3.11.0' }
     plugins {
-        grpc { artifact = 'io.grpc:protoc-gen-grpc-java:1.27.2' // CURRENT_GRPC_VERSION
+        grpc { artifact = "io.grpc:protoc-gen-grpc-java:$grpc_version"
         }
     }
     generateProtoTasks {
@@ -61,28 +63,28 @@ protobuf {
 }
 
 dependencies {
-    implementation 'androidx.appcompat:appcompat:1.0.0'
+    implementation 'androidx.appcompat:appcompat:1.6.0'
     implementation fileTree(dir: 'libs', include: ['*.jar'])
-    implementation 'androidx.constraintlayout:constraintlayout:1.1.3'
-    testImplementation 'junit:junit:4.12'
-    androidTestImplementation 'androidx.test:runner:1.2.0'
-    androidTestImplementation 'androidx.test.espresso:espresso-core:3.2.0'
+    implementation 'androidx.constraintlayout:constraintlayout:2.1.4'
+    testImplementation 'junit:junit:4.13.2'
+    androidTestImplementation 'androidx.test:runner:1.5.2'
+    androidTestImplementation 'androidx.test.espresso:espresso-core:3.5.1'
     implementation project(path: ':transfer_api')
 
     implementation 'org.tensorflow:tensorflow-lite:0.0.0-nightly-SNAPSHOT'
     // This dependency adds the necessary TF op support.
     implementation 'org.tensorflow:tensorflow-lite-select-tf-ops:0.0.0-nightly-SNAPSHOT'
 
-    implementation 'io.grpc:grpc-okhttp:1.27.2' // CURRENT_GRPC_VERSION
-    implementation 'io.grpc:grpc-protobuf-lite:1.27.2' // CURRENT_GRPC_VERSION
-    implementation 'io.grpc:grpc-stub:1.27.2' // CURRENT_GRPC_VERSION
-    implementation 'javax.annotation:javax.annotation-api:1.2'
+    implementation "io.grpc:grpc-okhttp:$grpc_version"
+    implementation "io.grpc:grpc-protobuf-lite:$grpc_version"
+    implementation "io.grpc:grpc-stub:$grpc_version"
+    implementation 'javax.annotation:javax.annotation-api:1.3.2'
 
-    def lifecycle_version = '2.1.0-rc01'
+    def lifecycle_version = '2.2.0'
     implementation "androidx.lifecycle:lifecycle-extensions:$lifecycle_version"
     implementation "androidx.lifecycle:lifecycle-common-java8:$lifecycle_version"
 
-    implementation 'com.google.android.material:material:1.0.0'
+    implementation 'com.google.android.material:material:1.7.0'
 
 }
 

examples/android/client/app/src/main/AndroidManifest.xml

@@ -1,6 +1,5 @@
 <?xml version="1.0" encoding="utf-8"?>
-<manifest xmlns:android="http://schemas.android.com/apk/res/android"
-    package="flwr.android_client">
+<manifest xmlns:android="http://schemas.android.com/apk/res/android">
 
     <uses-permission android:name="android.permission.INTERNET" />
     <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
@@ -12,13 +11,17 @@
         android:usesCleartextTraffic="true"
         android:supportsRtl="true"
         android:theme="@style/Theme.AppCompat.Light">
-        <activity android:name="flwr.android_client.MainActivity">
+        <activity android:name="flwr.android_client.MainActivity"
+            android:exported="true">
             <intent-filter>
                 <action android:name="android.intent.action.MAIN" />
 
                 <category android:name="android.intent.category.LAUNCHER" />
             </intent-filter>
         </activity>
+        <meta-data
+            android:name="preloaded_fonts"
+            android:resource="@array/preloaded_fonts" />
     </application>
 
-</manifest>
+</manifest>

examples/android/client/app/src/main/java/flwr/android_client/MainActivity.java

@@ -2,14 +2,12 @@
 
 import android.app.Activity;
 import android.icu.text.SimpleDateFormat;
-import android.os.AsyncTask;
-import android.os.Build;
 import android.os.Bundle;
 
-import androidx.annotation.RequiresApi;
 import androidx.appcompat.app.AppCompatActivity;
 
 import android.os.Handler;
+import android.os.Looper;
 import android.text.TextUtils;
 import android.text.method.ScrollingMovementMethod;
 import android.util.Log;
@@ -25,23 +23,23 @@
 import io.grpc.ManagedChannel;
 import io.grpc.ManagedChannelBuilder;
 
-import  flwr.android_client.FlowerServiceGrpc.FlowerServiceBlockingStub;
 import  flwr.android_client.FlowerServiceGrpc.FlowerServiceStub;
 import com.google.protobuf.ByteString;
 
 import io.grpc.stub.StreamObserver;
 
-import java.io.IOException;
-import java.io.InputStream;
 import java.io.PrintWriter;
 import java.io.StringWriter;
-import java.net.URL;
 import java.nio.ByteBuffer;
 import java.util.ArrayList;
 import java.util.Date;
 import java.util.List;
+import java.util.Locale;
+import java.util.Objects;
 import java.util.concurrent.CountDownLatch;
-import javax.net.ssl.HttpsURLConnection;
+import java.util.concurrent.ExecutorService;
+import java.util.concurrent.Executors;
+
 
 public class MainActivity extends AppCompatActivity {
     private EditText ip;
@@ -53,7 +51,7 @@ public class MainActivity extends AppCompatActivity {
     private EditText device_id;
     private ManagedChannel channel;
     public FlowerClient fc;
-    private static String TAG = "Flower";
+    private static final String TAG = "Flower";
 
     @Override
     protected void onCreate(Bundle savedInstanceState) {
@@ -82,7 +80,7 @@ public static void hideKeyboard(Activity activity) {
 
 
     public void setResultText(String text) {
-        SimpleDateFormat dateFormat = new SimpleDateFormat("HH:mm:ss");
+        SimpleDateFormat dateFormat = new SimpleDateFormat("HH:mm:ss", Locale.GERMANY);
         String time = dateFormat.format(new Date());
         resultText.append("\n" + time + "   " + text);
     }
@@ -99,15 +97,30 @@ else if (Integer.parseInt(device_id.getText().toString()) > 10 ||  Integer.parse
             hideKeyboard(this);
             setResultText("Loading the local training dataset in memory. It will take several seconds.");
             loadDataButton.setEnabled(false);
-            final Handler handler = new Handler();
-            handler.postDelayed(new Runnable() {
+
+            ExecutorService executor = Executors.newSingleThreadExecutor();
+            Handler handler = new Handler(Looper.getMainLooper());
+
+            executor.execute(new Runnable() {
+                private String result;
                 @Override
                 public void run() {
-                    fc.loadData(Integer.parseInt(device_id.getText().toString()));
-                    setResultText("Training dataset is loaded in memory.");
-                    connectButton.setEnabled(true);
+                    try {
+                        fc.loadData(Integer.parseInt(device_id.getText().toString()));
+                        result =  "Training dataset is loaded in memory.";
+                    } catch (Exception e) {
+                        StringWriter sw = new StringWriter();
+                        PrintWriter pw = new PrintWriter(sw);
+                        e.printStackTrace(pw);
+                        pw.flush();
+                        result =  "Training dataset is loaded in memory.";
+                    }
+                    handler.post(() -> {
+                        setResultText(result);
+                        connectButton.setEnabled(true);
+                    });
                 }
-            }, 1000);
+            });
         }
     }
 
@@ -118,7 +131,7 @@ public void connect(View view) {
             Toast.makeText(this, "Please enter the correct IP and port of the FL server", Toast.LENGTH_LONG).show();
         }
         else {
-            int port = TextUtils.isEmpty(portStr) ? 0 : Integer.valueOf(portStr);
+            int port = TextUtils.isEmpty(portStr) ? 0 : Integer.parseInt(portStr);
             channel = ManagedChannelBuilder.forAddress(host, port).maxInboundMessageSize(10 * 1024 * 1024).usePlaintext().build();
             hideKeyboard(this);
             trainButton.setEnabled(true);
@@ -127,61 +140,44 @@ public void connect(View view) {
         }
     }
 
-    public void runGRCP(View view){
-        new GrpcTask(new FlowerServiceRunnable(), channel, this).execute();
-    }
-
-    private static class GrpcTask extends AsyncTask<Void, Void, String> {
-        private final GrpcRunnable grpcRunnable;
-        private final ManagedChannel channel;
-        private final MainActivity activityReference;
-
-        GrpcTask(GrpcRunnable grpcRunnable, ManagedChannel channel, MainActivity activity) {
-            this.grpcRunnable = grpcRunnable;
-            this.channel = channel;
-            this.activityReference = activity;
-        }
-
-        @Override
-        protected String doInBackground(Void... nothing) {
-            try {
-                grpcRunnable.run(FlowerServiceGrpc.newBlockingStub(channel), FlowerServiceGrpc.newStub(channel), this.activityReference);
-                return "Connection to the FL server successful \n";
-            } catch (Exception e) {
-                StringWriter sw = new StringWriter();
-                PrintWriter pw = new PrintWriter(sw);
-                e.printStackTrace(pw);
-                pw.flush();
-                return "Failed to connect to the FL server \n" + sw;
-            }
-        }
-
-        @Override
-        protected void onPostExecute(String result) {
-            MainActivity activity = activityReference;
-            if (activity == null) {
-                return;
+    public void runGrpc(View view){
+        MainActivity activity = this;
+        ExecutorService executor = Executors.newSingleThreadExecutor();
+        Handler handler = new Handler(Looper.getMainLooper());
+
+        executor.execute(new Runnable() {
+            private String result;
+            @Override
+            public void run() {
+                try {
+                    (new FlowerServiceRunnable()).run(FlowerServiceGrpc.newStub(channel), activity);
+                    result =  "Connection to the FL server successful \n";
+                } catch (Exception e) {
+                    StringWriter sw = new StringWriter();
+                    PrintWriter pw = new PrintWriter(sw);
+                    e.printStackTrace(pw);
+                    pw.flush();
+                    result = "Failed to connect to the FL server \n" + sw;
+                }
+                handler.post(() -> {
+                    setResultText(result);
+                    trainButton.setEnabled(false);
+                });
             }
-            activity.setResultText(result);
-            activity.trainButton.setEnabled(false);
-        }
+        });
     }
 
-    private interface GrpcRunnable {
-        void run(FlowerServiceBlockingStub blockingStub, FlowerServiceStub asyncStub, MainActivity activity) throws Exception;
-    }
 
-    private static class FlowerServiceRunnable implements GrpcRunnable {
-        private Throwable failed;
+    private static class FlowerServiceRunnable{
+        protected Throwable failed;
         private StreamObserver<ClientMessage> requestObserver;
-        @Override
-        public void run(FlowerServiceBlockingStub blockingStub, FlowerServiceStub asyncStub, MainActivity activity)
-                throws Exception {
+
+        public void run(FlowerServiceStub asyncStub, MainActivity activity) {
              join(asyncStub, activity);
         }
 
         private void join(FlowerServiceStub asyncStub, MainActivity activity)
-                throws InterruptedException, RuntimeException {
+                throws RuntimeException {
 
             final CountDownLatch finishLatch = new CountDownLatch(1);
             requestObserver = asyncStub.join(
@@ -193,6 +189,7 @@ public void onNext(ServerMessage msg) {
 
                                 @Override
                                 public void onError(Throwable t) {
+                                    t.printStackTrace();
                                     failed = t;
                                     finishLatch.countDown();
                                     Log.e(TAG, t.getMessage());
@@ -212,7 +209,7 @@ private void handleMessage(ServerMessage message, MainActivity activity) {
                 ByteBuffer[] weights;
                 ClientMessage c = null;
 
-                if (message.hasGetParameters()) {
+                if (message.hasGetParametersIns()) {
                     Log.e(TAG, "Handling GetParameters");
                     activity.setResultText("Handling GetParameters message from the server.");
 
@@ -226,6 +223,7 @@ private void handleMessage(ServerMessage message, MainActivity activity) {
 
                     Scalar epoch_config = message.getFitIns().getConfigMap().getOrDefault("local_epochs", Scalar.newBuilder().setSint64(1).build());
 
+                    assert epoch_config != null;
                     int local_epochs = (int) epoch_config.getSint64();
 
                     // Our model has 10 layers
@@ -257,7 +255,6 @@ private void handleMessage(ServerMessage message, MainActivity activity) {
                 }
                 requestObserver.onNext(c);
                 activity.setResultText("Response sent to the server");
-                c = null;
             }
             catch (Exception e){
                 Log.e(TAG, e.getMessage());
@@ -266,19 +263,19 @@ private void handleMessage(ServerMessage message, MainActivity activity) {
     }
 
     private static ClientMessage weightsAsProto(ByteBuffer[] weights){
-        List<ByteString> layers = new ArrayList<ByteString>();
-        for (int i=0; i < weights.length; i++) {
-            layers.add(ByteString.copyFrom(weights[i]));
+        List<ByteString> layers = new ArrayList<>();
+        for (ByteBuffer weight : weights) {
+            layers.add(ByteString.copyFrom(weight));
         }
         Parameters p = Parameters.newBuilder().addAllTensors(layers).setTensorType("ND").build();
-        ClientMessage.ParametersRes res = ClientMessage.ParametersRes.newBuilder().setParameters(p).build();
-        return ClientMessage.newBuilder().setParametersRes(res).build();
+        ClientMessage.GetParametersRes res = ClientMessage.GetParametersRes.newBuilder().setParameters(p).build();
+        return ClientMessage.newBuilder().setGetParametersRes(res).build();
     }
 
     private static ClientMessage fitResAsProto(ByteBuffer[] weights, int training_size){
-        List<ByteString> layers = new ArrayList<ByteString>();
-        for (int i=0; i < weights.length; i++) {
-            layers.add(ByteString.copyFrom(weights[i]));
+        List<ByteString> layers = new ArrayList<>();
+        for (ByteBuffer weight : weights) {
+            layers.add(ByteString.copyFrom(weight));
         }
         Parameters p = Parameters.newBuilder().addAllTensors(layers).setTensorType("ND").build();
         ClientMessage.FitRes res = ClientMessage.FitRes.newBuilder().setParameters(p).setNumExamples(training_size).build();