Dart fix + Flutter upgrade

lib/pages/add_app.dart

@@ -39,7 +39,7 @@ class AddAppPageState extends State<AddAppPage> {
   int urlInputKey = 0;
   SourceProvider sourceProvider = SourceProvider();
 
-  linkFn(String input) {
+  void linkFn(String input) {
     try {
       if (input.isEmpty) {
         throw UnsupportedURLError();
@@ -51,7 +51,7 @@ class AddAppPageState extends State<AddAppPage> {
     }
   }
 
-  changeUserInput(
+  void changeUserInput(
     String input,
     bool valid,
     bool isBuilding, {

lib/pages/apps.dart

@@ -26,7 +26,7 @@ class AppsPage extends StatefulWidget {
   State<AppsPage> createState() => AppsPageState();
 }
 
-showChangeLogDialog(
+void showChangeLogDialog(
   BuildContext context,
   App app,
   String? changesUrl,
@@ -100,7 +100,7 @@ showChangeLogDialog(
   );
 }
 
-getChangeLogFn(BuildContext context, App app) {
+Null Function()? getChangeLogFn(BuildContext context, App app) {
   AppSource appSource = SourceProvider().getSource(
     app.url,
     overrideSource: app.overrideSource,
@@ -138,7 +138,7 @@ class AppsPageState extends State<AppsPage> {
   Set<String> selectedAppIds = {};
   DateTime? refreshingSince;
 
-  clearSelected() {
+  bool clearSelected() {
     if (selectedAppIds.isNotEmpty) {
       setState(() {
         selectedAppIds.clear();
@@ -148,7 +148,7 @@ class AppsPageState extends State<AppsPage> {
     return false;
   }
 
-  selectThese(List<App> apps) {
+  void selectThese(List<App> apps) {
     if (selectedAppIds.isEmpty) {
       setState(() {
         for (var a in apps) {
@@ -1063,6 +1063,7 @@ class AppsPageState extends State<AppsPage> {
                             globalNavigatorKey.currentContext ?? context,
                           )
                           .catchError(
+                            // ignore: invalid_return_type_for_catch_error
                             (e) => showError(
                               e,
                               globalNavigatorKey.currentContext ?? context,
@@ -1317,7 +1318,7 @@ class AppsFilter {
     };
   }
 
-  setFormValuesFromMap(Map<String, dynamic> values) {
+  void setFormValuesFromMap(Map<String, dynamic> values) {
     nameFilter = values['appName']!;
     authorFilter = values['author']!;
     idFilter = values['appId']!;

lib/pages/home.dart

@@ -229,7 +229,7 @@ class _HomePageState extends State<HomePage> {
     });
   }
 
-  setIsReversing(int targetIndex) {
+  void setIsReversing(int targetIndex) {
     bool reversing =
         selectedIndexHistory.isNotEmpty &&
         selectedIndexHistory.last > targetIndex;
@@ -238,7 +238,7 @@ class _HomePageState extends State<HomePage> {
     });
   }
 
-  switchToPage(int index) async {
+  Future<void> switchToPage(int index) async {
     setIsReversing(index);
     if (index == 0) {
       while ((pages[0].widget.key as GlobalKey<AppsPageState>).currentState !=
@@ -340,8 +340,8 @@ class _HomePageState extends State<HomePage> {
           });
           return false;
         }
-        return !(pages[0].widget.key as GlobalKey<AppsPageState>).currentState
-            ?.clearSelected();
+        return !(pages[0].widget.key as GlobalKey<AppsPageState>).currentState!
+            .clearSelected();
       },
     );
   }

lib/pages/import_export.dart

@@ -695,7 +695,7 @@ class _SelectionModalState extends State<SelectionModal> {
     }
   }
 
-  selectOnlyOne(String url) {
+  void selectOnlyOne(String url) {
     for (var e in entrySelections.keys) {
       entrySelections[e] = e.key == url;
     }