Hide QR code scanner on devices without cameras (#101)

android/app/src/main/kotlin/net/defined/mobile_nebula/MainActivity.kt

@@ -7,6 +7,7 @@ import android.content.Context
 import android.content.Intent
 import android.content.IntentFilter
 import android.content.ServiceConnection
+import android.content.pm.PackageManager
 import android.net.VpnService
 import android.os.*
 import android.util.Log
@@ -62,6 +63,7 @@ class MainActivity: FlutterActivity() {
         ui!!.setMethodCallHandler { call, result ->
             when(call.method) {
                 "android.registerActiveSite" -> registerActiveSite(result)
+                "android.deviceHasCamera" -> deviceHasCamera(result)
 
                 "nebula.parseCerts" -> nebulaParseCerts(call, result)
                 "nebula.generateKeyPair" -> nebulaGenerateKeyPair(result)
@@ -120,6 +122,10 @@ class MainActivity: FlutterActivity() {
         result.success(null)
     }
 
+    private fun deviceHasCamera(result: MethodChannel.Result) {
+        result.success(context.packageManager.hasSystemFeature(PackageManager.FEATURE_CAMERA_ANY))
+    }
+
     private fun nebulaParseCerts(call: MethodCall, result: MethodChannel.Result) {
         val certs = call.argument<String>("certs")
         if (certs == "") {

lib/screens/HostInfoScreen.dart

@@ -21,6 +21,7 @@ class HostInfoScreen extends StatefulWidget {
     required this.pending,
     this.onChanged,
     required this.site,
+    required this.supportsQRScanning,
   }) : super(key: key);
 
   final bool isLighthouse;
@@ -29,6 +30,8 @@ class HostInfoScreen extends StatefulWidget {
   final Function? onChanged;
   final Site site;
 
+  final bool supportsQRScanning;
+
   @override
   _HostInfoScreenState createState() => _HostInfoScreenState();
 }
@@ -72,7 +75,10 @@ class _HostInfoScreenState extends State<HostInfoScreen> {
               labelWidth: 150,
               content: Text(hostInfo.cert!.details.name),
               onPressed: () => Utils.openPage(
-                  context, (context) => CertificateDetailsScreen(certInfo: CertificateInfo(cert: hostInfo.cert!))))
+                  context, (context) => CertificateDetailsScreen(
+                    certInfo: CertificateInfo(cert: hostInfo.cert!),
+                    supportsQRScanning: widget.supportsQRScanning,
+              )))
           : Container(),
     ]);
   }

lib/screens/MainScreen.dart

@@ -74,6 +74,8 @@ class _MainScreenState extends State<MainScreen> {
   // A set of widgets to display in a column that represents an error blocking us from moving forward entirely
   List<Widget>? error;
 
+  bool supportsQRScanning = false;
+
   static const platform = MethodChannel('net.defined.mobileNebula/NebulaVpnService');
   RefreshController refreshController = RefreshController();
   ScrollController scrollController = ScrollController();
@@ -123,6 +125,16 @@ class _MainScreenState extends State<MainScreen> {
       );
     }
 
+    // Determine whether the device supports QR scanning. For example, some
+    // Chromebooks do not have camera support.
+    if (Platform.isAndroid) {
+      platform.invokeMethod("android.deviceHasCamera").then(
+              (hasCamera) => setState(() => supportsQRScanning = hasCamera)
+      );
+    } else {
+      supportsQRScanning = true;
+    }
+
     return SimplePage(
       title: Text('Nebula'),
       scrollable: SimpleScrollable.vertical,
@@ -133,12 +145,11 @@ class _MainScreenState extends State<MainScreen> {
         onPressed: () => Utils.openPage(context, (context) {
           return SiteConfigScreen(onSave: (_) {
             _loadSites();
-          });
+          }, supportsQRScanning: supportsQRScanning);
         }),
       ),
       refreshController: refreshController,
       onRefresh: () {
-        print("onRefresh");
         _loadSites();
         refreshController.refreshCompleted();
       },
@@ -198,7 +209,11 @@ class _MainScreenState extends State<MainScreen> {
           site: site,
           onPressed: () {
             Utils.openPage(context, (context) {
-              return SiteDetailScreen(site: site, onChanged: () => _loadSites());
+              return SiteDetailScreen(
+                  site: site,
+                  onChanged: () => _loadSites(),
+                  supportsQRScanning: supportsQRScanning,
+              );
             });
           }));
     });

lib/screens/SiteDetailScreen.dart

@@ -21,10 +21,16 @@ import 'package:pull_to_refresh/pull_to_refresh.dart';
 //TODO: ios is now the problem with connecting screwing our ability to query the hostmap (its a race)
 
 class SiteDetailScreen extends StatefulWidget {
-  const SiteDetailScreen({Key? key, required this.site, this.onChanged}) : super(key: key);
+  const SiteDetailScreen({
+    Key? key,
+    required this.site,
+    this.onChanged,
+    required this.supportsQRScanning,
+  }) : super(key: key);
 
   final Site site;
   final Function? onChanged;
+  final bool supportsQRScanning;
 
   @override
   _SiteDetailScreenState createState() => _SiteDetailScreenState();
@@ -193,7 +199,9 @@ class _SiteDetailScreenState extends State<SiteDetailScreen> {
                         setState(() {
                           activeHosts = hosts;
                         });
-                      }));
+                      },
+                      supportsQRScanning: widget.supportsQRScanning,
+                  ));
             },
             label: Text("Active"),
             content: Container(alignment: Alignment.centerRight, child: active)),
@@ -211,7 +219,9 @@ class _SiteDetailScreenState extends State<SiteDetailScreen> {
                         setState(() {
                           pendingHosts = hosts;
                         });
-                      }));
+                      },
+                      supportsQRScanning: widget.supportsQRScanning,
+                  ));
             },
             label: Text("Pending"),
             content: Container(alignment: Alignment.centerRight, child: pending))
@@ -231,7 +241,9 @@ class _SiteDetailScreenState extends State<SiteDetailScreen> {
                 onSave: (site) async {
                   changed = true;
                   setState(() {});
-                });
+                },
+              supportsQRScanning: widget.supportsQRScanning,
+            );
           });
         },
       ),

lib/screens/SiteTunnelsScreen.dart

@@ -10,8 +10,14 @@ import 'package:mobile_nebula/services/utils.dart';
 import 'package:pull_to_refresh/pull_to_refresh.dart';
 
 class SiteTunnelsScreen extends StatefulWidget {
-  const SiteTunnelsScreen(
+  const SiteTunnelsScreen({
-      {Key? key, required this.site, required this.tunnels, required this.pending, required this.onChanged})
+    Key? key,
+    required this.site,
+    required this.tunnels,
+    required this.pending,
+    required this.onChanged,
+    required this.supportsQRScanning,
+  })
       : super(key: key);
 
   final Site site;
@@ -19,6 +25,8 @@ class SiteTunnelsScreen extends StatefulWidget {
   final bool pending;
   final Function(List<HostInfo>)? onChanged;
 
+  final bool supportsQRScanning;
+
   @override
   _SiteTunnelsScreenState createState() => _SiteTunnelsScreenState();
 }
@@ -67,7 +75,10 @@ class _SiteTunnelsScreenState extends State<SiteTunnelsScreen> {
                 site: widget.site,
                 onChanged: () {
                   _listHostmap();
-                })),
+                },
+                supportsQRScanning: widget.supportsQRScanning,
+            ),
+        ),
         label: Row(children: <Widget>[Padding(child: icon, padding: EdgeInsets.only(right: 10)), Text(hostInfo.vpnIp)]),
         labelWidth: ipWidth,
         content: Container(alignment: Alignment.centerRight, child: Text(hostInfo.cert?.details.name ?? "")),

lib/screens/siteConfig/AddCertificateScreen.dart

@@ -30,6 +30,7 @@ class AddCertificateScreen extends StatefulWidget {
     this.onReplace,
     required this.pubKey,
     required this.privKey,
+    required this.supportsQRScanning,
   }) : super(key: key);
 
   // onSave will pop a new CertificateDetailsScreen.
@@ -42,6 +43,8 @@ class AddCertificateScreen extends StatefulWidget {
   final String pubKey;
   final String privKey;
 
+  final bool supportsQRScanning;
+
   @override
   _AddCertificateScreenState createState() => _AddCertificateScreenState();
 }
@@ -100,6 +103,16 @@ class _AddCertificateScreenState extends State<AddCertificateScreen> {
   }
 
   List<Widget> _buildLoadCert() {
+    Map<String, Widget> children = {
+      'paste': Text('Copy/Paste'),
+      'file': Text('File'),
+    };
+
+    // not all devices have a camera for QR codes
+    if (widget.supportsQRScanning) {
+      children['qr'] = Text('QR Code');
+    }
+
     List<Widget> items = [
       Padding(
           padding: EdgeInsets.fromLTRB(10, 25, 10, 0),
@@ -112,11 +125,7 @@ class _AddCertificateScreenState extends State<AddCertificateScreen> {
                 });
               }
             },
-            children: {
+            children: children,
-              'paste': Text('Copy/Paste'),
-              'file': Text('File'),
-              'qr': Text('QR Code'),
-            },
           ))
     ];
 
@@ -124,7 +133,7 @@ class _AddCertificateScreenState extends State<AddCertificateScreen> {
       items.addAll(_addPaste());
     } else if (inputType == 'file') {
       items.addAll(_addFile());
-    } else {
+    } else if (inputType == 'qr') {
       items.addAll(_addQr());
     }
 
@@ -257,7 +266,9 @@ class _AddCertificateScreenState extends State<AddCertificateScreen> {
                 onSave: () {
                   Navigator.pop(context);
                   widget.onSave!(CertificateResult(certInfo: tryCertInfo, key: keyController.text));
-                });
+                },
+                supportsQRScanning: widget.supportsQRScanning,
+            );
           });
         }
       }

lib/screens/siteConfig/CAListScreen.dart

@@ -21,11 +21,14 @@ class CAListScreen extends StatefulWidget {
     Key? key,
     required this.cas,
     this.onSave,
+    required this.supportsQRScanning,
   }) : super(key: key);
 
   final List<CertificateInfo> cas;
   final ValueChanged<List<CertificateInfo>>? onSave;
 
+  final bool supportsQRScanning;
+
   @override
   _CAListScreenState createState() => _CAListScreenState();
 }
@@ -88,7 +91,9 @@ class _CAListScreenState extends State<CAListScreen> {
                     changed = true;
                     cas.remove(key);
                   });
-                });
+                },
+                supportsQRScanning: widget.supportsQRScanning,
+            );
           });
         },
       ));
@@ -129,6 +134,16 @@ class _CAListScreenState extends State<CAListScreen> {
   }
 
   List<Widget> _addCA() {
+    Map<String, Widget> children = {
+      'paste': Text('Copy/Paste'),
+      'file': Text('File'),
+    };
+
+    // not all devices have a camera for QR codes
+    if (widget.supportsQRScanning) {
+      children['qr'] = Text('QR Code');
+    }
+
     List<Widget> items = [
       Padding(
           padding: EdgeInsets.fromLTRB(10, 25, 10, 0),
@@ -141,11 +156,7 @@ class _CAListScreenState extends State<CAListScreen> {
                 });
               }
             },
-            children: {
+            children: children,
-              'paste': Text('Copy/Paste'),
-              'file': Text('File'),
-              'qr': Text('QR Code'),
-            },
           ))
     ];
 

lib/screens/siteConfig/CertificateDetailsScreen.dart

@@ -18,6 +18,7 @@ class CertificateDetailsScreen extends StatefulWidget {
     this.onReplace,
     this.pubKey,
     this.privKey,
+    required this.supportsQRScanning,
   }) : super(key: key);
 
   final CertificateInfo certInfo;
@@ -35,6 +36,8 @@ class CertificateDetailsScreen extends StatefulWidget {
   final String? pubKey;
   final String? privKey;
 
+  final bool supportsQRScanning;
+
   @override
   _CertificateDetailsScreenState createState() => _CertificateDetailsScreenState();
 }
@@ -178,7 +181,9 @@ class _CertificateDetailsScreenState extends State<CertificateDetailsScreen> {
                               duration: const Duration(milliseconds: 10), curve: Curves.linearToEaseOut);
                         },
                         pubKey: widget.pubKey!,
-                        privKey: widget.privKey!);
+                        privKey: widget.privKey!,
+                        supportsQRScanning: widget.supportsQRScanning,
+                    );
                   });
                 })));
   }

lib/screens/siteConfig/SiteConfigScreen.dart

@@ -27,6 +27,7 @@ class SiteConfigScreen extends StatefulWidget {
     Key? key,
     this.site,
     required this.onSave,
+    required this.supportsQRScanning,
   }) : super(key: key);
 
   final Site? site;
@@ -34,6 +35,8 @@ class SiteConfigScreen extends StatefulWidget {
   // This is called after the target OS has saved the configuration
   final ValueChanged<Site> onSave;
 
+  final bool supportsQRScanning;
+
   @override
   _SiteConfigScreenState createState() => _SiteConfigScreenState();
 }
@@ -186,7 +189,9 @@ class _SiteConfigScreenState extends State<SiteConfigScreen> {
                         site.certInfo = result.certInfo;
                         site.key = result.key;
                       });
-                    });
+                    },
+                    supportsQRScanning: widget.supportsQRScanning,
+                );
               }
 
               return AddCertificateScreen(
@@ -198,7 +203,9 @@ class _SiteConfigScreenState extends State<SiteConfigScreen> {
                       site.certInfo = result.certInfo;
                       site.key = result.key;
                     });
-                  });
+                  },
+                supportsQRScanning: widget.supportsQRScanning,
+              );
             });
           },
         ),
@@ -222,7 +229,9 @@ class _SiteConfigScreenState extends State<SiteConfigScreen> {
                         changed = true;
                         site.ca = ca;
                       });
-                    });
+                    },
+                    supportsQRScanning: widget.supportsQRScanning,
+                );
               });
             })
       ],