diff --git a/lib/barcode.dart b/lib/barcode.dart
index 100c0d54..d43707c4 100644
--- a/lib/barcode.dart
+++ b/lib/barcode.dart
@@ -272,9 +272,6 @@ class StockItemBarcodeAssignmentHandler extends BarcodeHandler {
   final InvenTreeStockItem item;
 
   StockItemBarcodeAssignmentHandler(this.item) {
-    if (item == null) {
-      throw new AssertionError("null StockItem passed to barcode handler");
-    }
   }
 
   @override
@@ -354,11 +351,7 @@ class StockItemScanIntoLocationHandler extends BarcodeHandler {
 
   final InvenTreeStockItem item;
 
-  StockItemScanIntoLocationHandler(this.item) {
-    if (item == null) {
-      throw new AssertionError("null StockItem passed to StockItemScanIntoLocationHandler");
-    }
-  }
+  StockItemScanIntoLocationHandler(this.item);
 
   @override
   String getOverlayText(BuildContext context) => L10().barcodeScanLocation;
@@ -419,11 +412,7 @@ class StockLocationScanInItemsHandler extends BarcodeHandler {
   
   final InvenTreeStockLocation location;
   
-  StockLocationScanInItemsHandler(this.location) {
-    if (location == null) {
-      throw new AssertionError("null StockLocation passed to StockLocationScanInItemsHandler");
-    }
-  }
+  StockLocationScanInItemsHandler(this.location);
   
   @override
   String getOverlayText(BuildContext context) => L10().barcodeScanItem;
diff --git a/lib/inventree/model.dart b/lib/inventree/model.dart
index 9953c659..76d558b3 100644
--- a/lib/inventree/model.dart
+++ b/lib/inventree/model.dart
@@ -19,12 +19,8 @@ class InvenTreePageResponse {
   }
 
   // Total number of results in the dataset
-  int _count = 0;
-
-  void set count(int v) { _count = v; }
-
-  int get count => _count;
-
+  int count = 0;
+  
   int get length => results.length;
 
   List<InvenTreeModel> results = [];
diff --git a/lib/inventree/part.dart b/lib/inventree/part.dart
index 4cf593aa..22bee60f 100644
--- a/lib/inventree/part.dart
+++ b/lib/inventree/part.dart
@@ -48,9 +48,7 @@ class InvenTreePartCategory extends InvenTreeModel {
 
   InvenTreePartCategory() : super();
 
-  InvenTreePartCategory.fromJson(Map<String, dynamic> json) : super.fromJson(json) {
-
-  }
+  InvenTreePartCategory.fromJson(Map<String, dynamic> json) : super.fromJson(json);
 
   @override
   InvenTreeModel createFromJson(Map<String, dynamic> json) {
@@ -85,8 +83,7 @@ class InvenTreePartTestTemplate extends InvenTreeModel {
 
   InvenTreePartTestTemplate() : super();
 
-  InvenTreePartTestTemplate.fromJson(Map<String, dynamic> json) : super.fromJson(json) {
-  }
+  InvenTreePartTestTemplate.fromJson(Map<String, dynamic> json) : super.fromJson(json);
 
   @override
   InvenTreeModel createFromJson(Map<String, dynamic> json) {
@@ -309,11 +306,6 @@ class InvenTreePart extends InvenTreeModel {
         name: 'image',
       );
 
-      if (response == null) {
-        print("uploadImage returned null at '${url}'");
-        return false;
-      }
-
       if (response.statusCode != 200) {
         print("uploadImage returned ${response.statusCode} at '${url}'");
         return false;
diff --git a/lib/inventree/sentry.dart b/lib/inventree/sentry.dart
index da729e0a..4e4e4f2a 100644
--- a/lib/inventree/sentry.dart
+++ b/lib/inventree/sentry.dart
@@ -1,12 +1,8 @@
 import 'dart:io';
 
 import 'package:device_info/device_info.dart';
-import 'package:flutter/material.dart';
-import 'package:font_awesome_flutter/font_awesome_flutter.dart';
 import 'package:package_info/package_info.dart';
 import 'package:sentry_flutter/sentry_flutter.dart';
-import 'package:one_context/one_context.dart';
-import 'package:flutter_gen/gen_l10n/app_localizations.dart';
 
 import 'package:InvenTree/api.dart';
 
@@ -108,13 +104,14 @@ Future<bool> sentryReportMessage(String message, {Map<String, String>? context})
     }
   });
 
-  final sentryId = await Sentry.captureMessage(message).catchError((error) {
+  try {
+    await Sentry.captureMessage(message);
+    return true;
+  } catch (error) {
     print("Error uploading sentry messages...");
     print(error);
-    return null;
-  });
-
-  return sentryId != null;
+    return false;
+  }
 }
 
 
diff --git a/lib/inventree/stock.dart b/lib/inventree/stock.dart
index da2999fb..4242d79b 100644
--- a/lib/inventree/stock.dart
+++ b/lib/inventree/stock.dart
@@ -188,11 +188,11 @@ class InvenTreeStockItem extends InvenTreeModel {
       "result": result.toString(),
     };
 
-    if (value != null && !value.isEmpty) {
+    if (value != null && value.isNotEmpty) {
       data["value"] = value;
     }
 
-    if (notes != null && !notes.isEmpty) {
+    if (notes != null && notes.isNotEmpty) {
       data["notes"] = notes;
     }
 
@@ -211,8 +211,6 @@ class InvenTreeStockItem extends InvenTreeModel {
       // Check that the HTTP status code is HTTP_201_CREATED
       return _uploadResponse.statusCode == 201;
     }
-
-    return false;
   }
 
   String get uid => jsondata['uid'] ?? '';
diff --git a/lib/main.dart b/lib/main.dart
index a84abe83..ecf7097c 100644
--- a/lib/main.dart
+++ b/lib/main.dart
@@ -1,5 +1,4 @@
 import 'dart:async';
-import 'dart:io';
 
 import 'package:InvenTree/inventree/sentry.dart';
 import 'package:flutter_localizations/flutter_localizations.dart';
diff --git a/lib/preferences.dart b/lib/preferences.dart
index 27a416f0..f6e2372f 100644
--- a/lib/preferences.dart
+++ b/lib/preferences.dart
@@ -54,10 +54,6 @@ class InvenTreePreferencesDB {
 
 class InvenTreePreferences {
 
-  static const String _SERVER = 'server';
-  static const String _USERNAME = 'username';
-  static const String _PASSWORD = 'password';
-
   /* The following settings are not stored to persistent storage,
    * instead they are only used as 'session preferences'.
    * They are kept here as a convenience only.
diff --git a/lib/widget/company_list.dart b/lib/widget/company_list.dart
index f3cb207a..090784d3 100644
--- a/lib/widget/company_list.dart
+++ b/lib/widget/company_list.dart
@@ -9,7 +9,7 @@ import 'package:InvenTree/widget/refreshable_state.dart';
 
 abstract class CompanyListWidget extends StatefulWidget {
 
-  String title = "";
+  final String title = "";
   Map<String, String> filters = {};
 
   @override
diff --git a/lib/widget/dialogs.dart b/lib/widget/dialogs.dart
index 725b5e52..dfa7edcf 100644
--- a/lib/widget/dialogs.dart
+++ b/lib/widget/dialogs.dart
@@ -22,7 +22,7 @@ Future<void> confirmationDialog(String title, String text, {String? acceptText,
         ),
         content: Text(text),
         actions: [
-          FlatButton(
+          TextButton(
             child: Text(_reject),
             onPressed: () {
               // Close this dialog
@@ -33,7 +33,7 @@ Future<void> confirmationDialog(String title, String text, {String? acceptText,
               }
             }
           ),
-          FlatButton(
+          TextButton(
             child: Text(_accept),
             onPressed: () {
               // Close this dialog
@@ -176,7 +176,7 @@ void showFormDialog(String title, {String? acceptText, String? cancelText, Globa
   // Undefined actions = OK + Cancel
   if (actions == null) {
     actions = <Widget>[
-      FlatButton(
+      TextButton(
         child: Text(_cancel),
         onPressed: () {
           // Close the form
@@ -186,7 +186,7 @@ void showFormDialog(String title, {String? acceptText, String? cancelText, Globa
           }
         }
       ),
-      FlatButton(
+      TextButton(
         child: Text(_accept),
         onPressed: () {
 
diff --git a/lib/widget/fields.dart b/lib/widget/fields.dart
index 87a62477..53126604 100644
--- a/lib/widget/fields.dart
+++ b/lib/widget/fields.dart
@@ -71,13 +71,13 @@ class ImagePickerField extends FormField<File> {
             child: Row(
               mainAxisAlignment: MainAxisAlignment.spaceEvenly,
               children: <Widget>[
-                FlatButton(
+                TextButton(
                   child: Text(L10().selectImage),
                   onPressed: () {
                     _selectFromGallery(state);
                   },
                 ),
-                FlatButton(
+                TextButton(
                   child: Text(L10().takePicture),
                   onPressed: () {
                     _selectFromCamera(state);
diff --git a/lib/widget/search.dart b/lib/widget/search.dart
index 97ccde01..f6fb1c1b 100644
--- a/lib/widget/search.dart
+++ b/lib/widget/search.dart
@@ -199,9 +199,7 @@ class PartSearchDelegate extends SearchDelegate<InvenTreePart?> {
   // Ensure the search theme matches the app theme
   @override
   ThemeData appBarTheme(BuildContext context) {
-    assert(context != null);
     final ThemeData theme = Theme.of(context);
-    assert(theme != null);
     return theme;
   }
 }
@@ -389,9 +387,7 @@ class StockSearchDelegate extends SearchDelegate<InvenTreeStockItem?> {
   // Ensure the search theme matches the app theme
   @override
   ThemeData appBarTheme(BuildContext context) {
-    assert(context != null);
     final ThemeData theme = Theme.of(context);
-    assert(theme != null);
     return theme;
   }
 }
\ No newline at end of file
diff --git a/lib/widget/stock_detail.dart b/lib/widget/stock_detail.dart
index 2517c9dc..d8ef4a17 100644
--- a/lib/widget/stock_detail.dart
+++ b/lib/widget/stock_detail.dart
@@ -392,7 +392,7 @@ class _StockItemDisplayState extends RefreshableState<StockDetailWidget> {
     }
 
     // Location information
-    if ((item.locationId > 0) && (item.locationName != null) && (item.locationName.isNotEmpty)) {
+    if ((item.locationId > 0) && (item.locationName.isNotEmpty)) {
       tiles.add(
           ListTile(
             title: Text(L10().stockLocation),
@@ -581,7 +581,7 @@ class _StockItemDisplayState extends RefreshableState<StockDetailWidget> {
     );
 
     // Add or remove custom barcode
-    if (item != null && item.uid.isEmpty) {
+    if (item.uid.isEmpty) {
       tiles.add(
         ListTile(
           title: Text(L10().barcodeAssign),