Added alarm history to project and renaming

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

 import androidx.appcompat.app.AppCompatActivity;
 import androidx.lifecycle.Observer;
 import androidx.lifecycle.ViewModelProvider;
+import androidx.recyclerview.widget.LinearLayoutManager;
+import androidx.recyclerview.widget.RecyclerView;
 
 import android.hardware.Sensor;
 import android.hardware.SensorEvent;
 import android.widget.TextView;
 import android.widget.Toast;
 
+import com.example.greenwatch.adapters.AlarmHistoryListAdapter;
+import com.example.greenwatch.adapters.DeviceListAdapter;
 import com.example.greenwatch.models.Device;
 import com.example.greenwatch.viewmodels.AccelerometerViewModel;
 
         accelerometerWarningTV = (TextView) findViewById(R.id.tvAccelerometerWarning);
         backToMainActivityButton = (Button) findViewById(R.id.accelerometerBackToMainActivity);
 
+        RecyclerView recyclerView = findViewById(R.id.deviceListRecyclerView);
+        recyclerView.setLayoutManager(new LinearLayoutManager(this));
+        recyclerView.setHasFixedSize(true);
+
+        final DeviceListAdapter deviceListAdapter = new DeviceListAdapter();
+        recyclerView.setAdapter(deviceListAdapter);
+
+        RecyclerView alarmHistoryListRecyclerView = findViewById(R.id.alarmHistoryListRecyclerView);
+        alarmHistoryListRecyclerView.setLayoutManager(new LinearLayoutManager(this));
+        alarmHistoryListRecyclerView.setHasFixedSize(true);
+
+        final AlarmHistoryListAdapter alarmHistoryListAdapter  = new AlarmHistoryListAdapter();
+        alarmHistoryListRecyclerView.setAdapter(alarmHistoryListAdapter);
+
         backToMainActivityButton.setOnClickListener(new View.OnClickListener() {
             @Override
             public void onClick(View v) {
         mAccelerometerViewModel.getConnectedDeviceList().observe(this, new Observer<List<Device>>() {
             @Override
             public void onChanged(List<Device> devices) {
-                StringBuilder sb = new StringBuilder();
-                sb.append("Time Stamp: ");
-                sb.append(mAccelerometerViewModel.getTimeStamp(mAccelerometerViewModel.getLocalDeviceUUID()));
-                sb.append(";\n");
-                sb.append("DeviceID: ");
-                sb.append(mAccelerometerViewModel.getDeviceID(mAccelerometerViewModel.getLocalDeviceUUID()));
-                sb.append(";\n");
-                sb.append("Sensor Status: ");
-                sb.append(mAccelerometerViewModel.getSensorStatus(mAccelerometerViewModel.getLocalDeviceUUID()));
-                sb.append(";\n");
-                sb.append("Sensor Type: ");
-                sb.append(mAccelerometerViewModel.getSensorType(mAccelerometerViewModel.getLocalDeviceUUID()));
-                sb.append(";\n");
-                sb.append("Sensor Massage: ");
-                sb.append(mAccelerometerViewModel.getSensorMassage(mAccelerometerViewModel.getLocalDeviceUUID()));
-                accelerometerStatusMessage.setText(sb);
+                deviceListAdapter.setDevices(devices);
                 Toast.makeText(AccelerometerActivity.this, "onChanged", Toast.LENGTH_LONG).show();
             }
         });
 
+        mAccelerometerViewModel.getAlarmHistoryList().observe(this, new Observer<List<Device>>() {
+            @Override
+            public void onChanged(List<Device> devices) {
+                alarmHistoryListAdapter.setAlarmHistoryList(devices);
+            }
+        });
+
         mAccelerometerViewModel.getMovementDetectedValue().observe(this, new Observer<Boolean>() {
             @Override
             public void onChanged(Boolean aBoolean) {
                 if (aBoolean) {
-                    mAccelerometerViewModel.setDevice(mAccelerometerViewModel.getLocalDeviceUUID(), mAccelerometerViewModel.getSystemTimeStamp(), true, "Accelerometer", 10);
+                    mAccelerometerViewModel.updateDevice(mAccelerometerViewModel.getLocalDeviceUUID(), mAccelerometerViewModel.getSystemTimeStamp(), true, "Accelerometer", 10);
                 }
                 else {
-                    mAccelerometerViewModel.setDevice(mAccelerometerViewModel.getLocalDeviceUUID(), mAccelerometerViewModel.getSystemTimeStamp(), false, "Accelerometer", 0);
+                    mAccelerometerViewModel.updateDevice(mAccelerometerViewModel.getLocalDeviceUUID(), mAccelerometerViewModel.getSystemTimeStamp(), false, "Accelerometer", 0);
                 }
 
             }

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

 import android.os.Bundle;
 import android.view.View;
 import android.widget.Button;
-import android.widget.TextView;
 import android.widget.Toast;
 
+import com.example.greenwatch.adapters.AlarmHistoryListAdapter;
 import com.example.greenwatch.adapters.DeviceListAdapter;
 import com.example.greenwatch.models.Device;
 import com.example.greenwatch.viewmodels.MainActivityViewModel;
 
 public class MainActivity extends AppCompatActivity {
 
-    private TextView tvstatusmessage;
     private Button audiodetectionButton;
     private Button videodetectionButton;
     private Button accelerometerButton;
         super.onCreate(savedInstanceState);
         setContentView(R.layout.activity_main);
 
-        tvstatusmessage = (TextView) findViewById(R.id.tvStatusmessage);
         audiodetectionButton = (Button) findViewById(R.id.audiodetectionButton);
         videodetectionButton = (Button) findViewById(R.id.videodetectionButton);
         accelerometerButton = (Button) findViewById(R.id.accelerometerButton);
         videodetectionAndAccelerometerButton = (Button) findViewById(R.id.videodetectionAndAccelerometerButton);
         connectionButton = (Button) findViewById(R.id.connectionButton);
 
-        RecyclerView recyclerView = findViewById(R.id.deviceListRecyclerView);
-        recyclerView.setLayoutManager(new LinearLayoutManager(this));
-        recyclerView.setHasFixedSize(true);
+        RecyclerView deviceListRecyclerView = findViewById(R.id.deviceListRecyclerView);
+        deviceListRecyclerView.setLayoutManager(new LinearLayoutManager(this));
+        deviceListRecyclerView.setHasFixedSize(true);
 
         final DeviceListAdapter deviceListAdapter = new DeviceListAdapter();
-        recyclerView.setAdapter(deviceListAdapter);
+        deviceListRecyclerView.setAdapter(deviceListAdapter);
+
+        RecyclerView alarmHistoryListRecyclerView = findViewById(R.id.alarmHistoryListRecyclerView);
+        alarmHistoryListRecyclerView.setLayoutManager(new LinearLayoutManager(this));
+        alarmHistoryListRecyclerView.setHasFixedSize(true);
+
+        final AlarmHistoryListAdapter alarmHistoryListAdapter  = new AlarmHistoryListAdapter();
+        alarmHistoryListRecyclerView.setAdapter(alarmHistoryListAdapter);
 
         mMainActivityViewModel = new ViewModelProvider(this).get(MainActivityViewModel.class);
         mMainActivityViewModel.init();
             @Override
             public void onChanged(List<Device> devices) {
                 deviceListAdapter.setDevices(devices);
-                StringBuilder sb = new StringBuilder();
-                sb.append("Time Stamp: ");
-                sb.append(mMainActivityViewModel.getTimeStamp(mMainActivityViewModel.getLocalDeviceUUID()));
-                sb.append(";\n");
-                sb.append("DeviceID: ");
-                sb.append(mMainActivityViewModel.getDeviceID(mMainActivityViewModel.getLocalDeviceUUID()));
-                sb.append(";\n");
-                sb.append("Sensor Status: ");
-                sb.append(mMainActivityViewModel.getSensorStatus(mMainActivityViewModel.getLocalDeviceUUID()));
-                sb.append(";\n");
-                sb.append("Sensor Type: ");
-                sb.append(mMainActivityViewModel.getSensorType(mMainActivityViewModel.getLocalDeviceUUID()));
-                sb.append(";\n");
-                sb.append("Sensor Massage: ");
-                sb.append(mMainActivityViewModel.getSensorMassage(mMainActivityViewModel.getLocalDeviceUUID()));
-                tvstatusmessage.setText(sb);
                 Toast.makeText(MainActivity.this, "onChanged", Toast.LENGTH_LONG).show();
             }
         });
 
+        mMainActivityViewModel.getAlarmHistoryList().observe(this, new Observer<List<Device>>() {
+            @Override
+            public void onChanged(List<Device> devices) {
+                alarmHistoryListAdapter.setAlarmHistoryList(devices);
+            }
+        });
+
         audiodetectionButton.setOnClickListener(new View.OnClickListener() {
             @Override
             public void onClick(View v) {
                 //openAudiodetectionActivity();
-                mMainActivityViewModel.setDevice(mMainActivityViewModel.getLocalDeviceUUID(), "10:51",  false, "Audio", 10);
+                mMainActivityViewModel.updateDevice(mMainActivityViewModel.getLocalDeviceUUID(), "10:51",  false, "Audio", 10);
             }
         });
         videodetectionButton.setOnClickListener(new View.OnClickListener() {
     public void openVideodetectionAndAccelerometerActivity(){
         //Intent intent = new Intent(this, VideodetectionAndAccelerometerActivity.class);
         //startActivity(intent);
-        mMainActivityViewModel.setDevice(mMainActivityViewModel.getLocalDeviceUUID(), "24:00",  false, "Video", 0);
+        mMainActivityViewModel.updateDevice(mMainActivityViewModel.getLocalDeviceUUID(), "24:00",  false, "Video", 0);
     }
     public void openConnectionActivity(){
         //Intent intent = new Intent(this, ConnectionActivity.class);
         //startActivity(intent);
-        mMainActivityViewModel.setDevice(mMainActivityViewModel.getLocalDeviceUUID(), "10:51",  true, "Audio", 10);
+        mMainActivityViewModel.updateDevice(mMainActivityViewModel.getLocalDeviceUUID(), "10:51",  true, "Audio", 10);
     }
 
 }

app/src/main/java/com/example/greenwatch/adapters/AlarmHistoryListAdapter.java

+package com.example.greenwatch.adapters;
+
+import android.view.LayoutInflater;
+import android.view.View;
+import android.view.ViewGroup;
+import android.widget.TextView;
+
+import androidx.annotation.NonNull;
+import androidx.recyclerview.widget.RecyclerView;
+
+import com.example.greenwatch.R;
+import com.example.greenwatch.models.Device;
+
+import java.util.ArrayList;
+import java.util.List;
+
+public class AlarmHistoryListAdapter extends RecyclerView.Adapter<AlarmHistoryListAdapter.AlarmHistoryListHolder> {
+    private List<Device> alarmHistoryList = new ArrayList<>();
+
+
+    @NonNull
+    @Override
+    public AlarmHistoryListHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
+        View itemView = LayoutInflater.from(parent.getContext())
+                .inflate(R.layout.alarm_history_item, parent, false);
+        return new AlarmHistoryListHolder(itemView);
+    }
+
+    @Override
+    public void onBindViewHolder(@NonNull AlarmHistoryListHolder holder, int position) {
+        Device currentDevice = alarmHistoryList.get(position);
+        holder.textViewSensorType.setText(holder.itemView.getContext().getString(R.string.sensor_type_placeholder, currentDevice.getSensorType()));
+        holder.textViewDeviceID.setText(holder.itemView.getContext().getString(R.string.deviceID_placeholder, currentDevice.getDeviceID()));
+        holder.textViewTimeStamp.setText(holder.itemView.getContext().getString(R.string.sensor_time_stamp_placeholder, currentDevice.getTimeStamp()));
+        holder.textViewSensorMessage.setText(holder.itemView.getContext().getString(R.string.sensor_message_placeholder, currentDevice.getSensorMassage()));
+    }
+
+    @Override
+    public int getItemCount() {
+        return alarmHistoryList.size();
+    }
+
+    public void setAlarmHistoryList(List<Device> alarmHistoryList) {
+        this.alarmHistoryList = alarmHistoryList;
+        notifyDataSetChanged();
+    }
+
+    class AlarmHistoryListHolder extends RecyclerView.ViewHolder {
+        private TextView textViewSensorType;
+        private TextView textViewDeviceID;
+        private TextView textViewTimeStamp;
+        private TextView textViewSensorMessage;
+
+        public AlarmHistoryListHolder(View itemView) {
+            super(itemView);
+            textViewSensorType = (TextView) itemView.findViewById(R.id.tvAlarmHistoryDeviceSensorType);
+            textViewDeviceID = (TextView) itemView.findViewById(R.id.tvAlarmHistoryDeviceID);
+            textViewTimeStamp = (TextView) itemView.findViewById(R.id.tvAlarmHistoryDeviceTimeStamp);
+            textViewSensorMessage = (TextView) itemView.findViewById(R.id.tvAlarmHistoryDeviceSensorMassage);
+        }
+    }
+}

app/src/main/java/com/example/greenwatch/repositories/DeviceRepository.java

 import com.example.greenwatch.models.Device;
 import com.example.greenwatch.communication.WiFiCommunication;
 
+import java.text.SimpleDateFormat;
 import java.util.ArrayList;
+import java.util.Date;
 import java.util.HashMap;
 import java.util.List;
 import java.util.UUID;
 
 public class DeviceRepository {
 
+    private final int maxAlarmHistoryListSize = 20;
     private final String delimiter = ", ";
     private final String SensorStatusKey = "An";
     private String localDeviceUUID;
     private static DeviceRepository deviceRepositoryInstance;
     private WiFiCommunication mWiFiCommunication;
     private MutableLiveData<List<Device>> deviceList = new MutableLiveData<>();
+    private MutableLiveData<List<Device>> alarmHistoryList = new MutableLiveData<>();
     private HashMap<String, Device> connectedDevicesList = new HashMap<>();
     private HashMap<String, String> deviceIDMapper = new HashMap<>();
+    private List<Device> alarmHistoryDeviceList = new ArrayList<>();
 
     private DeviceRepository() {
         setLocalDeviceUUID();
     }
 
     public MutableLiveData<List<Device>> getConnectedDeviceList() {
-        setMutableLiveDataValue();
+        setMutableLiveDataDeviceList();
         return deviceList;
     }
 
+    public MutableLiveData<List<Device>> getAlarmHistoryDeviceList() {
+        setMutableLiveDataAlarmHistoryList();
+        return alarmHistoryList;
+    }
+
     public void createNewDevice(String timeStamp, String deviceID, boolean sensorStatus, String sensorType, int sensorMassage){
         Device newDevice = new Device(timeStamp, deviceID, sensorStatus, sensorType, sensorMassage);
-        setDeviceIDMapper(deviceID);
+        if (sensorStatus) {
+            setAlarmHistoryDeviceList(newDevice);
+        }
         addToConnectedDeviceList(newDevice.getDeviceID(), newDevice);
-        setMutableLiveDataValue();
+        setMutableLiveDataDeviceList();
+    }
+
+    public void getNewReceivedMessage(String newMessage) {
+        String[] messageString = messageStringSplitter(newMessage);
+        String timeStamp = messageString[0];
+        String deviceID = messageString[1];
+        boolean sensorStatus = convertSensorStatus(messageString[2]);
+        String sensorType = messageString[3];
+        int sensorMassage = Integer.valueOf(messageString[4]);
+
+        if (deviceID.equals(checkDeviceID(localDeviceUUID))) {
+            return;
+        }
+
+        if(!connectedDevicesList.containsKey(deviceID)) {
+            createNewDevice(timeStamp, deviceID, sensorStatus, sensorType, sensorMassage);
+        }
+        else {
+            updateDevice(deviceID, timeStamp, sensorStatus, sensorType, sensorMassage);
+        }
     }
 
     private String messageStringBuilder(String deviceID) {
                     .append(device.getSensorType())
                     .append(delimiter)
                     .append(device.getSensorMassage());
-            return message.toString();
         }
         else {
             message.append("")
                     .append("")
                     .append(delimiter)
                     .append("");
-            return message.toString();
         }
+        return message.toString();
     }
 
     public String getLocalDeviceUUID() {
         Device device = connectedDevicesList.get(checkedDeviceID);
         if(device != null) {
             device.setTimeStamp(timeStamp);
-            device.setSensorStatus(sensorStatus);
             device.setSensorType(sensorType);
             device.setSensorMassage(sensorMassage);
+            if (!device.getSensorStatus() && sensorStatus) {
+                setAlarmHistoryDeviceList(device);
+            }
+            device.setSensorStatus(sensorStatus);
             addToConnectedDeviceList(checkedDeviceID, device);
-            setMutableLiveDataValue();
+            setMutableLiveDataDeviceList();
         }
     }
 
         if(device != null) {
             device.setTimeStamp(timeStamp);
             addToConnectedDeviceList(checkedDeviceID, device);
-            setMutableLiveDataValue();
+            setMutableLiveDataDeviceList();
         }
     }
 
             setDeviceIDMapper(newDeviceID);
             connectedDevicesList.remove(checkedDeviceID);
             addToConnectedDeviceList(newDeviceID, device);
-            setMutableLiveDataValue();
+            setMutableLiveDataDeviceList();
         }
     }
 
         String checkedDeviceID = checkDeviceID(deviceID);
         Device device = connectedDevicesList.get(checkedDeviceID);
         if(device != null) {
+            if (!device.getSensorStatus() && sensorStatus) {
+                setAlarmHistoryDeviceList(device);
+            }
             device.setSensorStatus(sensorStatus);
             addToConnectedDeviceList(checkedDeviceID, device);
-            setMutableLiveDataValue();
+            setMutableLiveDataDeviceList();
+
         }
     }
 
         if(device != null) {
             device.setSensorType(sensorType);
             addToConnectedDeviceList(checkedDeviceID, device);
-            setMutableLiveDataValue();
+            setMutableLiveDataDeviceList();
         }
     }
 
         if(device != null) {
             device.setSensorMassage(sensorMessage);
             addToConnectedDeviceList(checkedDeviceID, device);
-            setMutableLiveDataValue();
+            setMutableLiveDataDeviceList();
         }
     }
 
         return 0;
     }
 
-    private void setMutableLiveDataValue() {
+    public String getSystemTimeStamp() {
+        SimpleDateFormat formatter = new SimpleDateFormat("HH:mm:ss");
+        Date date = new Date(System.currentTimeMillis());
+        return formatter.format(date);
+    }
+
+    private void setMutableLiveDataDeviceList() {
         List<Device> list = new ArrayList<>(connectedDevicesList.values());
         deviceList.setValue(list);
     }
 
+    private void setMutableLiveDataAlarmHistoryList() {
+        alarmHistoryList.setValue(alarmHistoryDeviceList);
+    }
+
     private void addToConnectedDeviceList(String key, Device device) {
         connectedDevicesList.put(key, device);
         if (key.equals(checkDeviceID(localDeviceUUID))) {
         return message.split(delimiter);
     }
 
-    public void getNewReceivedMessage(String newMessage) {
-        String[] messageString = messageStringSplitter(newMessage);
-        String timeStamp = messageString[0];
-        String deviceID = messageString[1];
-        boolean sensorStatus = convertSensorStatus(messageString[2]);
-        String sensorType = messageString[3];
-        int sensorMassage = Integer.valueOf(messageString[4]);
-
-        if (deviceID.equals(checkDeviceID(localDeviceUUID))) {
-            return;
-        }
-
-        if(!connectedDevicesList.containsKey(deviceID)) {
-            createNewDevice(timeStamp, deviceID, sensorStatus, sensorType, sensorMassage);
-        }
-        else {
-            updateDevice(deviceID, timeStamp, sensorStatus, sensorType, sensorMassage);
-        }
-    }
-
     private boolean convertSensorStatus(String status) {
         return status.equals(SensorStatusKey);
     }
+
+    private void setAlarmHistoryDeviceList(Device device) {
+        if (alarmHistoryDeviceList.size() == maxAlarmHistoryListSize) {
+            alarmHistoryDeviceList.remove(alarmHistoryDeviceList.size() -1);
+        }
+        Device alarmHistoryDevice = new Device(device.getTimeStamp(), device.getDeviceID(), device.getSensorStatus(), device.getSensorType(), device.getSensorMassage());
+        alarmHistoryDeviceList.add(0, alarmHistoryDevice);
+        setMutableLiveDataAlarmHistoryList();
+    }
 }

app/src/main/java/com/example/greenwatch/viewmodels/AccelerometerViewModel.java

 
     private MutableLiveData<List<Device>> mDeviceList;
     private MutableLiveData<Boolean> mMovementDetected = new MutableLiveData<>();
+    private MutableLiveData<List<Device>> mAlarmHistoryList;
     private DeviceRepository mDeviceRepository;
     private ArrayList<Float> Gesamt_be;
     int arraySize = 500;
         if (mDeviceList == null) {
             mDeviceRepository = DeviceRepository.getInstance();
             mDeviceList = mDeviceRepository.getConnectedDeviceList();
+            mAlarmHistoryList = mDeviceRepository.getAlarmHistoryDeviceList();
         }
         initGesamtBE();
         mMovementDetected.setValue(false);
     }
 
     public String getSystemTimeStamp() {
-        SimpleDateFormat formatter = new SimpleDateFormat("HH:mm:ss");
-        Date date = new Date(System.currentTimeMillis());
-        return formatter.format(date);
+        return mDeviceRepository.getSystemTimeStamp();
     }
 
     public LiveData<Boolean> getMovementDetectedValue() {
         return mDeviceList;
     }
 
-    public void setDevice(String deviceID, String timeStamp, boolean sensorStatus, String sensorType, int sensorMassage) {
+    public LiveData<List<Device>> getAlarmHistoryList() {
+        return mAlarmHistoryList;
+    }
+
+    public void updateDevice(String deviceID, String timeStamp, boolean sensorStatus, String sensorType, int sensorMassage) {
         mDeviceRepository.updateDevice(deviceID, timeStamp, sensorStatus, sensorType, sensorMassage);
     }
 

app/src/main/java/com/example/greenwatch/viewmodels/MainActivityViewModel.java

 public class MainActivityViewModel extends ViewModel {
 
     private MutableLiveData<List<Device>> mDeviceList;
+    private MutableLiveData<List<Device>> mAlarmHistoryList;
     private DeviceRepository mDeviceRepository;
 
 
         mWiFiCommunication = WiFiCommunication.getInstance();
         mDeviceRepository.setWiFiCommunication(mWiFiCommunication);
         mWiFiCommunication.setDeviceRepository(mDeviceRepository);
-        mDeviceRepository.createNewDevice("", mDeviceRepository.getLocalDeviceUUID(), false, "No Sensor selected", 0);
+        mDeviceRepository.createNewDevice(mDeviceRepository.getSystemTimeStamp(), mDeviceRepository.getLocalDeviceUUID(), false, "No Sensor selected", 0);
+        mDeviceRepository.createNewDevice("00:00", "1234", true, "Test", 21);
         mDeviceList = mDeviceRepository.getConnectedDeviceList();
+        mAlarmHistoryList = mDeviceRepository.getAlarmHistoryDeviceList();
     }
 
     public LiveData<List<Device>> getConnectedDeviceList() {
         return mDeviceList;
     }
 
-    public void setDevice(String deviceID, String timeStamp, boolean sensorStatus, String sensorType, int sensorMassage) {
+    public LiveData<List<Device>> getAlarmHistoryList() {
+        return mAlarmHistoryList;
+    }
+
+    public void updateDevice(String deviceID, String timeStamp, boolean sensorStatus, String sensorType, int sensorMassage) {
         mDeviceRepository.updateDevice(deviceID, timeStamp, sensorStatus, sensorType, sensorMassage);
     }
 

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

         android:text="Back to MainActivity">
     </Button>
 
+    <LinearLayout
+        android:layout_width="match_parent"
+        android:layout_height="match_parent"
+        android:orientation="vertical">
+
+        <androidx.recyclerview.widget.RecyclerView
+            android:id="@+id/deviceListRecyclerView"
+            android:layout_width="match_parent"
+            android:layout_height="match_parent"
+            tools:listitem="@layout/device_item"
+            android:layout_weight="1">
+        </androidx.recyclerview.widget.RecyclerView>
+
+        <androidx.recyclerview.widget.RecyclerView
+            android:id="@+id/alarmHistoryListRecyclerView"
+            android:layout_width="match_parent"
+            android:layout_height="match_parent"
+            tools:listitem="@layout/alarm_history_item"
+            android:layout_weight="1">
+        </androidx.recyclerview.widget.RecyclerView>
+
+    </LinearLayout>
+
 </LinearLayout>

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

     android:padding="10dp"
     tools:context=".MainActivity">
 
-    <TextView
-        android:id="@+id/tvStatusmessage"
+    <androidx.recyclerview.widget.RecyclerView
+        android:id="@+id/alarmHistoryListRecyclerView"
         android:layout_width="match_parent"
         android:layout_height="match_parent"
-        android:text="Hello World!"
-        android:layout_weight="4">
-    </TextView>
+        android:layout_weight="3"
+        tools:listitem="@layout/alarm_history_item">
+    </androidx.recyclerview.widget.RecyclerView>
 
     <androidx.recyclerview.widget.RecyclerView
         android:id="@+id/deviceListRecyclerView"
         android:layout_width="match_parent"
         android:layout_height="match_parent"
-        android:layout_weight="2"
+        android:layout_weight="3"
         tools:listitem="@layout/device_item">
     </androidx.recyclerview.widget.RecyclerView>
     

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

+<?xml version="1.0" encoding="utf-8"?>
+<androidx.cardview.widget.CardView xmlns:android="http://schemas.android.com/apk/res/android"
+    android:layout_width="match_parent"
+    android:layout_height="wrap_content"
+    android:layout_marginEnd="8dp"
+    android:layout_marginStart="8dp"
+    android:layout_marginTop="8dp">
+
+    <RelativeLayout
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:padding="8dp">
+
+        <TextView
+            android:id="@+id/tvAlarmHistoryDeviceSensorType"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:text="@string/sensor_type_placeholder"
+            android:textAppearance="@style/TextAppearance.AppCompat.Large"
+            android:maxLines="1"
+            android:layout_alignParentStart="true"
+            android:ellipsize="end">
+        </TextView>
+
+        <TextView
+            android:id="@+id/tvAlarmHistoryDeviceID"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:layout_below="@id/tvAlarmHistoryDeviceSensorType"
+            android:text="@string/deviceID_placeholder">
+        </TextView>
+
+        <TextView
+            android:id="@+id/tvAlarmHistoryDeviceTimeStamp"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:layout_below="@id/tvAlarmHistoryDeviceID"
+            android:text="@string/sensor_time_stamp_placeholder">
+        </TextView>
+
+        <TextView
+            android:id="@+id/tvAlarmHistoryDeviceSensorMassage"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:layout_below="@id/tvAlarmHistoryDeviceTimeStamp"
+            android:text="@string/sensor_message_placeholder">
+        </TextView>
+
+    </RelativeLayout>
+
+</androidx.cardview.widget.CardView>