diff --git a/safeDispatch/src/main/java/com/safemobile/dispatch/HistoryActivity.java b/safeDispatch/src/main/java/com/safemobile/dispatch/HistoryActivity.java
index 28fd336..46276d2 100644
--- a/safeDispatch/src/main/java/com/safemobile/dispatch/HistoryActivity.java
+++ b/safeDispatch/src/main/java/com/safemobile/dispatch/HistoryActivity.java
@@ -10,12 +10,9 @@ import android.graphics.drawable.ColorDrawable;
 import android.os.Bundle;
 import android.os.Handler;
 import android.util.Log;
-import android.view.View;
 import android.widget.ArrayAdapter;
 import android.widget.Button;
-import android.widget.DatePicker;
 import android.widget.ImageView;
-import android.widget.LinearLayout;
 import android.widget.Spinner;
 import android.widget.TextView;
 
@@ -23,11 +20,8 @@ import com.google.android.gms.maps.CameraUpdateFactory;
 import com.google.android.gms.maps.GoogleMap;
 import com.google.android.gms.maps.OnMapReadyCallback;
 import com.google.android.gms.maps.SupportMapFragment;
-import com.google.android.gms.maps.model.BitmapDescriptor;
-import com.google.android.gms.maps.model.BitmapDescriptorFactory;
 import com.google.android.gms.maps.model.LatLng;
 import com.google.android.gms.maps.model.MarkerOptions;
-import com.google.android.gms.maps.model.Polyline;
 import com.google.android.gms.maps.model.PolylineOptions;
 import com.safemobile.lib.AppParams;
 import com.safemobile.lib.HistPos;
@@ -47,18 +41,14 @@ public class HistoryActivity extends AppCompatActivity implements OnMapReadyCall
     private TabLayoutActivity parentTab;
     private GoogleMap googleMap;
     private Spinner spinnerVehicle;
-    private ImageView changeMapType, checkTraffic, slideLayoutImage;
-    private LinearLayout layoutTraffic, slidelayout, layoutVehicles;
     private Button displayButton;
     private Date startDate, endDate;
     private final Handler myHandler = new Handler();
     private GoogleMapsInfoBubble infoBubble;
 
-    private ArrayList<Vehicle> allVehicle = new ArrayList<>();
-    private ArrayList<String> allVehicleNames = new ArrayList<>();
-    private ArrayAdapter<String> adapter;
-    private boolean showVehicle = true;
-    private SimpleDateFormat sdf = new SimpleDateFormat("MMMM dd yyyy");
+    private final ArrayList<Vehicle> allVehicle = new ArrayList<>();
+    private final ArrayList<String> allVehicleNames = new ArrayList<>();
+    private final SimpleDateFormat sdf = new SimpleDateFormat("MMMM dd yyyy");
 
 
     @Override
@@ -75,12 +65,13 @@ public class HistoryActivity extends AppCompatActivity implements OnMapReadyCall
 
         SupportMapFragment mapFragment = (SupportMapFragment) getSupportFragmentManager()
                 .findFragmentById(R.id.map);
-        mapFragment.getMapAsync(this);
+        if (mapFragment != null)
+            mapFragment.getMapAsync(this);
 
         spinnerVehicle = findViewById(R.id.spinnerVehicle);
         getVehicles();
 
-        adapter = new ArrayAdapter<>(this, android.R.layout.simple_spinner_item, allVehicleNames);
+        ArrayAdapter<String> adapter = new ArrayAdapter<>(this, android.R.layout.simple_spinner_item, allVehicleNames);
         adapter.setDropDownViewResource(android.R.layout.simple_dropdown_item_1line);
         spinnerVehicle.setAdapter(adapter);
         spinnerVehicle.setSelection(0);
@@ -88,9 +79,6 @@ public class HistoryActivity extends AppCompatActivity implements OnMapReadyCall
         changeMapType();
         changeTraffic();
 
-        slidelayout = findViewById(R.id.slidelayout);
-        slideLayoutImage = findViewById(R.id.slideLayoutImage);
-        layoutVehicles = findViewById(R.id.layoutBig);
         displayButton = findViewById(R.id.buttonDisplay);
         displayButton.setOnClickListener(view -> {
             googleMap.clear();
@@ -127,7 +115,7 @@ public class HistoryActivity extends AppCompatActivity implements OnMapReadyCall
             }
         }
 
-        Polyline polyline1 = googleMap.addPolyline(polylineOptions);
+        googleMap.addPolyline(polylineOptions);
         if (latLng != null)
             googleMap.moveCamera(CameraUpdateFactory.newLatLngZoom(latLng, 14));
     }
@@ -138,7 +126,6 @@ public class HistoryActivity extends AppCompatActivity implements OnMapReadyCall
         calendar.add(Calendar.DATE, -1);
         startDate = calendar.getTime();
 
-        LinearLayout layoutStartPicker = findViewById(R.id.layoutStartPicker);
         TextView textViewStartDate = findViewById(R.id.textViewStartDate);
         TextView textViewEndDate = findViewById(R.id.textViewEndDate);
 
@@ -187,14 +174,13 @@ public class HistoryActivity extends AppCompatActivity implements OnMapReadyCall
     }
 
     private void changeMapType() {
-        changeMapType = findViewById(R.id.changeMapType);
-        ImageView changeMapTypeImageView = findViewById(R.id.changeMapType);
+        ImageView changeMapType = findViewById(R.id.changeMapType);
         changeMapType.setOnClickListener(view -> {
             if (googleMap.getMapType() == GoogleMap.MAP_TYPE_SATELLITE) {
-                changeMapTypeImageView.setImageResource(R.drawable.satellite);
+                changeMapType.setImageResource(R.drawable.satellite);
                 googleMap.setMapType(GoogleMap.MAP_TYPE_SATELLITE);
             } else {
-                changeMapTypeImageView.setImageResource(R.drawable.map);
+                changeMapType.setImageResource(R.drawable.map);
                 googleMap.setMapType(GoogleMap.MAP_TYPE_NORMAL);
             }
         });
@@ -202,11 +188,13 @@ public class HistoryActivity extends AppCompatActivity implements OnMapReadyCall
 
     public void getVehicles() {
         try {
+            allVehicle.clear();
+            allVehicleNames.clear();
             for (Vehicle vehicle : parentTab.getAllVehicle()) {
                 allVehicleNames.add(vehicle.name);
                 allVehicle.add(vehicle);
             }
-        } catch (Exception ex) { }
+        } catch (Exception ignored) { }
 
     }