dart fix --apply --code=prefer_is_empty

lib/components/SiteItem.dart

@@ -14,7 +14,7 @@ class SiteItem extends StatelessWidget {
   @override
   Widget build(BuildContext context) {
     final borderColor =
-        site.errors.length > 0
+        site.errors.isNotEmpty
             ? CupertinoColors.systemRed.resolveFrom(context)
             : site.connected
             ? CupertinoColors.systemGreen.resolveFrom(context)

lib/components/SpecialTextField.dart

@@ -64,7 +64,7 @@ class _SpecialTextFieldState extends State<SpecialTextField> {
 
   @override
   void initState() {
-    if (widget.inputFormatters == null || formatters.length == 0) {
+    if (widget.inputFormatters == null || formatters.isEmpty) {
       formatters = [FilteringTextInputFormatter.allow(RegExp(r'[^\t]'))];
     } else {
       formatters = widget.inputFormatters!;

lib/screens/HostInfoScreen.dart

@@ -108,7 +108,7 @@ class _HostInfoScreenState extends State<HostInfoScreen> {
   }
 
   Widget _buildRemotes() {
-    if (hostInfo.remoteAddresses.length == 0) {
+    if (hostInfo.remoteAddresses.isEmpty) {
       return ConfigSection(
         label: 'REMOTES',
         children: [ConfigItem(content: Text('No remote addresses yet'), labelWidth: 0)],
@@ -150,7 +150,7 @@ class _HostInfoScreenState extends State<HostInfoScreen> {
       );
     });
 
-    return ConfigSection(label: items.length > 0 ? 'Tap to change the active address' : null, children: items);
+    return ConfigSection(label: items.isNotEmpty ? 'Tap to change the active address' : null, children: items);
   }
 
   Widget _buildStaticRemotes() {
@@ -171,7 +171,7 @@ class _HostInfoScreenState extends State<HostInfoScreen> {
       );
     });
 
-    return ConfigSection(label: items.length > 0 ? 'REMOTES' : null, children: items);
+    return ConfigSection(label: items.isNotEmpty ? 'REMOTES' : null, children: items);
   }
 
   Widget _buildClose() {

lib/screens/MainScreen.dart

@@ -202,7 +202,7 @@ class _MainScreenState extends State<MainScreen> {
   }
 
   Widget _buildSites() {
-    if (sites == null || sites!.length == 0) {
+    if (sites == null || sites!.isEmpty) {
       return _buildNoSites();
     }
 

lib/screens/SiteDetailScreen.dart

@@ -112,7 +112,7 @@ class _SiteDetailScreenState extends State<SiteDetailScreen> {
   }
 
   Widget _buildErrors() {
-    if (site.errors.length == 0) {
+    if (site.errors.isEmpty) {
       return Container();
     }
 
@@ -165,7 +165,7 @@ class _SiteDetailScreenState extends State<SiteDetailScreen> {
               Switch.adaptive(
                 value: widget.site.connected,
                 materialTapTargetSize: MaterialTapTargetSize.shrinkWrap,
-                onChanged: widget.site.errors.length > 0 && !widget.site.connected ? null : handleChange,
+                onChanged: widget.site.errors.isNotEmpty && !widget.site.connected ? null : handleChange,
               ),
             ],
           ),

lib/screens/siteConfig/AddCertificateScreen.dart

@@ -245,7 +245,7 @@ class _AddCertificateScreenState extends State<AddCertificateScreen> {
       var rawCerts = await platform.invokeMethod("nebula.parseCerts", <String, String>{"certs": rawCert});
 
       List<dynamic> certs = jsonDecode(rawCerts);
-      if (certs.length > 0) {
+      if (certs.isNotEmpty) {
         var tryCertInfo = CertificateInfo.fromJson(certs.first);
         if (tryCertInfo.cert.details.isCa) {
           return Utils.popError(

lib/screens/siteConfig/CAListScreen.dart

@@ -51,7 +51,7 @@ class _CAListScreenState extends State<CAListScreen> {
     List<Widget> items = [];
     final caItems = _buildCAs();
 
-    if (caItems.length > 0) {
+    if (caItems.isNotEmpty) {
       items.add(ConfigSection(children: caItems));
     }
 

lib/screens/siteConfig/CertificateDetailsScreen.dart

@@ -120,19 +120,19 @@ class _CertificateDetailsScreenState extends State<CertificateDetailsScreen> {
 
   Widget _buildFilters() {
     List<Widget> items = [];
-    if (certInfo.cert.details.groups.length > 0) {
+    if (certInfo.cert.details.groups.isNotEmpty) {
       items.add(ConfigItem(label: Text('Groups'), content: SelectableText(certInfo.cert.details.groups.join(', '))));
     }
 
-    if (certInfo.cert.details.ips.length > 0) {
+    if (certInfo.cert.details.ips.isNotEmpty) {
       items.add(ConfigItem(label: Text('IPs'), content: SelectableText(certInfo.cert.details.ips.join(', '))));
     }
 
-    if (certInfo.cert.details.subnets.length > 0) {
+    if (certInfo.cert.details.subnets.isNotEmpty) {
       items.add(ConfigItem(label: Text('Subnets'), content: SelectableText(certInfo.cert.details.subnets.join(', '))));
     }
 
-    return items.length > 0
+    return items.isNotEmpty
         ? ConfigSection(label: certInfo.cert.details.isCa ? 'FILTERS' : 'DETAILS', children: items)
         : Container();
   }

lib/screens/siteConfig/SiteConfigScreen.dart

@@ -161,7 +161,7 @@ class _SiteConfigScreenState extends State<SiteConfigScreen> {
     final certError = site.certInfo == null || site.certInfo!.validity == null || !site.certInfo!.validity!.valid;
     var caError = false;
     if (!site.managed) {
-      caError = site.ca.length == 0;
+      caError = site.ca.isEmpty;
       if (!caError) {
         site.ca.forEach((ca) {
           if (ca.validity == null || !ca.validity!.valid) {
@@ -272,13 +272,13 @@ class _SiteConfigScreenState extends State<SiteConfigScreen> {
             alignment: WrapAlignment.end,
             crossAxisAlignment: WrapCrossAlignment.center,
             children: <Widget>[
-              site.staticHostmap.length == 0
+              site.staticHostmap.isEmpty
                   ? Padding(
                     padding: EdgeInsets.only(right: 5),
                     child: Icon(Icons.error, color: CupertinoColors.systemRed.resolveFrom(context), size: 20),
                   )
                   : Container(),
-              site.staticHostmap.length == 0
+              site.staticHostmap.isEmpty
                   ? Text('Needs attention')
                   : Text(Utils.itemCountFormat(site.staticHostmap.length)),
             ],

lib/screens/siteConfig/StaticHostmapScreen.dart

@@ -54,7 +54,7 @@ class _StaticHostmapScreenState extends State<StaticHostmapScreen> {
       _destinations[UniqueKey()] = _IPAndPort(focusNode: FocusNode(), destination: dest);
     });
 
-    if (_destinations.length == 0) {
+    if (_destinations.isEmpty) {
       _addDestination();
     }