Einbinden und Aufruf der Klasse WifiCommunication.java in Zusammenhang mit Eingabe, Sendebutton und Anzeige im Layout. Internet-Permission wurde dafür im Manifest eingetragen.

app/build.gradle

@@ -25,7 +25,6 @@ android {
         sourceCompatibility JavaVersion.VERSION_1_8
         targetCompatibility JavaVersion.VERSION_1_8
     }
-    namespace 'com.example.greenwatch'
 }
 
 dependencies {
@@ -36,10 +35,4 @@ dependencies {
     testImplementation 'junit:junit:4.13.2'
     androidTestImplementation 'androidx.test.ext:junit:1.1.5'
     androidTestImplementation 'androidx.test.espresso:espresso-core:3.5.1'
-
-    def camerax_version = "1.2.3"
-    implementation "androidx.camera:camera-camera2:${camerax_version}"
-    implementation "androidx.camera:camera-lifecycle:${camerax_version}"
-    implementation "androidx.camera:camera-view:${camerax_version}"
-
 }

app/src/main/AndroidManifest.xml

@@ -1,15 +1,9 @@
 <?xml version="1.0" encoding="utf-8"?>
-<manifest xmlns:android="http://schemas.android.com/apk/res/android">
+<manifest xmlns:android="http://schemas.android.com/apk/res/android"
+    package="com.example.greenwatch">
 
-    <uses-permission android:name="android.permission.RECORD_AUDIO"/>
-    <uses-permission android:name="android.permission.CAMERA"/>
-    <uses-permission android:name="android.permission.BLUETOOTH"/>
-    <uses-permission android:name="android.permission.BLUETOOTH_ADMIN"/>
-    <uses-permission android:name="android.permission.ACCESS_WIFI_STATE" />
     <uses-permission android:name="android.permission.INTERNET" />
 
-    <uses-feature android:name="android.hardware.camera"/>
-
     <application
         android:allowBackup="true"
         android:icon="@mipmap/ic_launcher"
@@ -26,9 +20,6 @@
                 <category android:name="android.intent.category.LAUNCHER" />
             </intent-filter>
         </activity>
-
-        <activity android:name=".KameraAktivitaet" />
-
     </application>
 
 </manifest>

app/src/main/java/com/example/greenwatch/KameraAktivitaet.java

@@ -1,59 +0,0 @@
-package com.example.greenwatch;
-
-import android.graphics.ImageFormat;
-import android.media.Image;
-import android.os.Bundle;
-import android.util.Size;
-
-import androidx.appcompat.app.AppCompatActivity;
-import androidx.camera.core.CameraSelector;
-import androidx.camera.core.ImageAnalysis;
-import androidx.camera.core.Preview;
-import androidx.camera.lifecycle.ProcessCameraProvider;
-import androidx.camera.view.PreviewView;
-import androidx.core.content.ContextCompat;
-
-import com.google.common.util.concurrent.ListenableFuture;
-
-import java.util.concurrent.ExecutionException;
-
-public class KameraAktivitaet extends AppCompatActivity {
-    private PreviewView previewView;
-
-    @Override
-    protected void onCreate(Bundle savedInstanceState) {
-        super.onCreate(savedInstanceState);
-        setContentView(R.layout.activity_demo_kamera2_nebenaktivitaet);
-        previewView = findViewById(R.id.previewView);
-        final ListenableFuture<ProcessCameraProvider> cameraProviderFuture = ProcessCameraProvider.getInstance(this);
-        cameraProviderFuture.addListener(() -> {
-            try {
-                bindImageAnalysis(cameraProviderFuture.get());
-            } catch (ExecutionException | InterruptedException e) {
-                e.printStackTrace();
-            }
-        }, ContextCompat.getMainExecutor(this));
-    }
-
-    private void bindImageAnalysis(ProcessCameraProvider cameraProvider) {
-        ImageAnalysis.Builder builder = new ImageAnalysis.Builder();
-        builder.setTargetResolution(new Size(640, 480));
-        builder.setBackpressureStrategy(ImageAnalysis.STRATEGY_KEEP_ONLY_LATEST);
-        ImageAnalysis imageAnalysis = builder.build();
-        imageAnalysis.setAnalyzer(
-                ContextCompat.getMainExecutor(this),
-                imageProxy -> {
-                    int imageFormat = imageProxy.getFormat();
-                    if (imageFormat == ImageFormat.YUV_420_888) {
-                        Image image = imageProxy.getImage();
-                    }
-                    imageProxy.close();
-                });
-
-        Preview preview = new Preview.Builder().build();
-        CameraSelector cameraSelector = new CameraSelector.Builder().requireLensFacing(CameraSelector.LENS_FACING_BACK).build();
-        preview.setSurfaceProvider(previewView.getSurfaceProvider());
-        cameraProvider.bindToLifecycle(this, cameraSelector, imageAnalysis, preview);
-    }
-}
-

app/src/main/java/com/example/greenwatch/MainActivity.java

@@ -1,40 +1,56 @@
 package com.example.greenwatch;
 
-import android.content.Intent;
-import android.content.pm.PackageManager;
-import android.os.Bundle;
-import android.widget.Button;
-
 import androidx.appcompat.app.AppCompatActivity;
-import androidx.core.app.ActivityCompat;
+
-import androidx.core.content.ContextCompat;
+import android.annotation.SuppressLint;
+import android.os.Bundle;
+import android.view.View;
+import android.widget.Button;
+import android.widget.EditText;
+import android.widget.TextView;
+import java.net.SocketException;
 
 public class MainActivity extends AppCompatActivity {
-    private static final int RECHTEANFORDERUNG_KAMERA = 10;
+    WifiCommunication communication; //Member WifiCommunication
+    TextView tvReceivedData; //Test Textview um empfangene Daten anzuzeigen -> Gegen finale Textview in der Anzeige austauschen
+    //ToDo: Falls finale Textview zum Anzeigen der Nachricht anders heißt, muss das in der Klasse WifiCommunication.java angepasst werden!
+    // Wo anpassen: Receive Thread, Zeile 58
+    private EditText etSendMessage; //Test Edittext um eine Nachricht zu senden -> gegen Nachricht von den Sensoren austauschen
+    private Button btnSend; //Test Sendebutton
 
+    private String sendmsg = "default";
+
+    @SuppressLint("MissingInflatedId")
     @Override
     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         setContentView(R.layout.activity_main);
-        Button kameraStarten = findViewById(R.id.button_camera);
+
-        kameraStarten.setOnClickListener(v -> {
+        xmlToJava(); //Funktionsaufruf, wo die Testbuttons etc angelegt sind
-            if (istZugriffAufKameraErlaubt()) {
-                starteKameraAktivitaet();
-            } else {
-                zugriffAufKameraAnfordern();
-            }
-        });
     }
 
-    private boolean istZugriffAufKameraErlaubt() {
+    public void xmlToJava(){
-        return ContextCompat.checkSelfPermission(this, android.Manifest.permission.CAMERA) == PackageManager.PERMISSION_GRANTED;
+        tvReceivedData = findViewById(R.id.tvRecTxt);       //Test Textview
+        etSendMessage = findViewById(R.id.sendMessage);     //Test Nachricht
+        btnSend = findViewById(R.id.btnSend);               //Test Sendebefehl
     }
 
-    private void zugriffAufKameraAnfordern() {
+    public void onClickSend(View view) throws SocketException{  //ToDo: Sendebefehl mit boolscher Variable lösen --> wo setzen?
-        ActivityCompat.requestPermissions(this,new String[]{android.Manifest.permission.CAMERA}, RECHTEANFORDERUNG_KAMERA);
+        sendmsg = etSendMessage.getText().toString();           //ToDo: hier String von Sensoren übergeben
+        communication.setMessage(sendmsg, true);    //übergibt zu sendenden String und setzt die entscheidende Boolsche Variable fürs Senden
     }
 
-    private void starteKameraAktivitaet() {
+    @Override
-        startActivity(new Intent(this, KameraAktivitaet.class));
+    protected void onResume() {
+        super.onResume();
+        //Erstellen des Members
+        communication = new WifiCommunication(MainActivity.this, MainActivity.this, 1234);
+    }
+
+    @Override
+    protected void onPause() {
+        super.onPause();
+        //schließt socket
+        communication.stopCommunication();
     }
 }

app/src/main/java/com/example/greenwatch/WifiCommunication.java

@@ -0,0 +1,124 @@
+package com.example.greenwatch;
+
+import android.annotation.SuppressLint;
+import android.content.Context;
+import android.widget.Toast;
+
+import java.io.IOException;
+import java.net.DatagramPacket;
+import java.net.DatagramSocket;
+import java.net.Inet4Address;
+import java.net.InetAddress;
+import java.net.NetworkInterface;
+import java.net.SocketException;
+import java.net.UnknownHostException;
+import java.util.Enumeration;
+
+public class WifiCommunication {
+    private final MainActivity mainActivity;
+    private final InetAddress address;
+    private final int port;
+    private final Context context;
+    private boolean newMsg;
+    private String rxString;
+    private String sendMsg;
+    //private String sendMsg = "default";
+    private final DatagramSocket socket;
+    volatile private boolean running;
+    @SuppressLint("SetTextI18n")
+    public WifiCommunication(MainActivity mainActivity, Context context, int port) {
+        this.mainActivity = mainActivity;
+        this.port = port;
+        this.context = context;
+        try {
+            socket = new DatagramSocket(this.port);
+            socket.setBroadcast(true);
+            address = InetAddress.getByName("255.255.255.255");
+            running = true;
+            new ReceiveThread().start();
+            new SendThread().start();
+        } catch (SocketException | UnknownHostException e) {
+            throw new RuntimeException(e);
+        }
+        mainActivity.runOnUiThread(() -> Toast.makeText(context,"Communication running", Toast.LENGTH_SHORT).show());
+    }
+    private class ReceiveThread extends Thread {
+        private String rxString = "";
+        private String previousRxString = "";
+        @Override
+        public void run() {
+            try {
+                do {
+
+                    byte[] rxBuffer = new byte[1024];
+                    DatagramPacket packet = new DatagramPacket(rxBuffer, rxBuffer.length);
+                    socket.receive(packet);
+                    rxString = new String(packet.getData(), 0, packet.getLength());
+
+                    if(!previousRxString.equals(rxString))
+                        mainActivity.runOnUiThread(() -> mainActivity.tvReceivedData.setText(rxString));
+
+                    previousRxString = rxString;
+
+                } while (running);
+            }
+            catch (IOException e) {
+                e.printStackTrace();
+            }
+        }
+    }
+
+    public String showMessage(){
+        return rxString;
+    }
+    public void setMessage(String message, boolean newMsg){
+        this.sendMsg=message;
+        this.newMsg = newMsg;
+    }
+    private class SendThread extends Thread {
+        private int tmpCnt = 0;
+        @Override
+        public void run() {
+            try {
+                do {
+
+                    if(newMsg == true)
+                    {
+                        newMsg = false;
+
+                        String txString = getLocalIpAddress() + " sends. #" + tmpCnt++ + sendMsg;
+                        byte[] txBuffer = txString.getBytes();
+
+                        DatagramPacket txPacket = new DatagramPacket(txBuffer, txBuffer.length, address, port);
+
+                        for(int i = 0; i < 20; i++) {
+                            socket.send(txPacket);
+                        }
+                    }
+                } while (running);
+            } catch (IOException e) {
+                e.printStackTrace();
+            }
+        }
+    }
+    public static String getLocalIpAddress() {
+        try {
+            for (Enumeration<NetworkInterface> en = NetworkInterface.getNetworkInterfaces(); en.hasMoreElements();) {
+                NetworkInterface networkInterface = (NetworkInterface) ((Enumeration<?>) en).nextElement();
+                for (Enumeration<InetAddress> addresses = networkInterface.getInetAddresses(); addresses.hasMoreElements();) {
+                    InetAddress inetAddress = addresses.nextElement();
+                    if (!inetAddress.isLoopbackAddress() && inetAddress instanceof Inet4Address) {
+                        return inetAddress.getHostAddress();
+                    }
+                }
+            }
+        } catch (SocketException ex) {
+            ex.printStackTrace();
+        }
+        return null;
+    }
+    public void stopCommunication() {
+        running = false;
+        socket.close();
+    }
+}

app/src/main/res/layout/activity_demo_kamera2_nebenaktivitaet.xml

@@ -1,41 +0,0 @@
-<?xml version="1.0" encoding="utf-8"?>
-<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
-    xmlns:app="http://schemas.android.com/apk/res-auto"
-    xmlns:tools="http://schemas.android.com/tools"
-    android:layout_width="match_parent"
-    android:layout_height="match_parent"
-    tools:context=".KameraAktivitaet">
-
-    <FrameLayout
-        android:layout_width="match_parent"
-        android:layout_height="match_parent"
-        android:id="@+id/erklaerung">
-        <androidx.camera.view.PreviewView
-            android:id="@+id/previewView"
-            android:layout_width="match_parent"
-            android:layout_height="match_parent"/>
-    </FrameLayout>
-    <LinearLayout
-        android:layout_width="match_parent"
-        android:layout_height="match_parent"
-        android:orientation="vertical">
-
-        <TextView
-            android:id="@+id/alarm"
-            android:layout_width="match_parent"
-            android:layout_height="0dp"
-            android:layout_weight="1"
-            android:text="" />
-
-        <TextView
-            android:id="@+id/luminanz"
-            android:layout_width="match_parent"
-            android:layout_height="0dp"
-            android:layout_weight="1"
-            android:layout_gravity="center"
-            android:gravity="center"
-            android:textSize="100sp"
-            android:textColor="#9999ff"/>
-    </LinearLayout>
-
-</androidx.constraintlayout.widget.ConstraintLayout>

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

@@ -6,17 +6,31 @@
     android:layout_height="match_parent"
     tools:context=".MainActivity">
 
-    <Button
+    <TextView
-        android:id="@+id/button_camera"
+        android:id="@+id/tvRecTxt"
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
-        android:text="Kamera starten"
+        android:text="Received Message"
-        app:layout_constraintBottom_toBottomOf="parent"
+        app:layout_constraintTop_toBottomOf="@id/sendMessage"
-        app:layout_constraintEnd_toEndOf="parent"
+        app:layout_constraintStart_toStartOf="parent"/>
-        app:layout_constraintHorizontal_bias="0.129"
-        app:layout_constraintStart_toStartOf="parent"
-        app:layout_constraintTop_toTopOf="parent"
-        app:layout_constraintVertical_bias="0.931" />
 
+    <EditText
+        android:id="@+id/sendMessage"
+        android:layout_width="wrap_content"
+        android:layout_height="50dp"
+        android:ems="10"
+        android:inputType="textPersonName"
+        android:text="Send Message"
+        app:layout_constraintTop_toTopOf="parent"
+        app:layout_constraintStart_toStartOf="parent"/>
+
+    <Button
+        android:id="@+id/btnSend"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:text="Send"
+        android:onClick="onClickSend"
+        app:layout_constraintTop_toTopOf="parent"
+        app:layout_constraintStart_toEndOf="@id/sendMessage"/>
 
 </androidx.constraintlayout.widget.ConstraintLayout>

build.gradle

@@ -1,7 +1,7 @@
 // Top-level build file where you can add configuration options common to all sub-projects/modules.
 plugins {
-    id 'com.android.application' version '8.0.0' apply false
+    id 'com.android.application' version '7.1.3' apply false
-    id 'com.android.library' version '8.0.0' apply false
+    id 'com.android.library' version '7.1.3' apply false
 }
 
 task clean(type: Delete) {

gradle.properties

@@ -18,6 +18,4 @@ android.useAndroidX=true
 # Enables namespacing of each library's R class so that its R class includes only the
 # resources declared in the library itself and none from the library's dependencies,
 # thereby reducing the size of the R class for that library
-android.nonTransitiveRClass=true
+android.nonTransitiveRClass=true
-android.defaults.buildfeatures.buildconfig=true
-android.nonFinalResIds=false

gradle/wrapper/gradle-wrapper.properties

@@ -1,6 +1,6 @@
 #Thu May 11 14:50:16 CEST 2023
 distributionBase=GRADLE_USER_HOME
-distributionUrl=https\://services.gradle.org/distributions/gradle-8.0-bin.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-7.2-bin.zip
 distributionPath=wrapper/dists
 zipStorePath=wrapper/dists
 zipStoreBase=GRADLE_USER_HOME