Reduce code duplication by introducing an OnBoardingButton

lib/screens/onboarding_git_url.dart

@@ -77,19 +77,55 @@ class OnBoardingGitUrlState extends State<OnBoardingGitUrl> {
           child: inputForm,
         ),
         SizedBox(height: 8.0),
-        SizedBox(
+        OnBoardingButton(
-          width: double.infinity,
+          text: "Next",
-          child: RaisedButton(
-            child: Text(
-              "Next",
-              textAlign: TextAlign.center,
-              style: Theme.of(context).textTheme.button,
-            ),
-            color: Theme.of(context).primaryColor,
           onPressed: formSubmitted,
         ),
-        )
       ],
     );
   }
 }
+
+class OnBoardingButton extends StatelessWidget {
+  final Function onPressed;
+  final String text;
+  final String iconUrl;
+
+  OnBoardingButton({
+    @required this.text,
+    @required this.onPressed,
+    this.iconUrl,
+  });
+
+  @override
+  Widget build(BuildContext context) {
+    if (iconUrl == null) {
+      return SizedBox(
+        width: double.infinity,
+        child: RaisedButton(
+          child: Text(
+            text,
+            textAlign: TextAlign.center,
+            style: Theme.of(context).textTheme.button,
+          ),
+          color: Theme.of(context).primaryColor,
+          onPressed: onPressed,
+        ),
+      );
+    } else {
+      return SizedBox(
+        width: double.infinity,
+        child: RaisedButton.icon(
+          label: Text(
+            text,
+            textAlign: TextAlign.center,
+            style: Theme.of(context).textTheme.button,
+          ),
+          icon: Image.asset(iconUrl, width: 32, height: 32),
+          color: Theme.of(context).primaryColor,
+          onPressed: onPressed,
+        ),
+      );
+    }
+  }
+}

lib/screens/onboarding_screens.dart

@@ -336,20 +336,9 @@ class OnBoardingCreateRepo extends StatelessWidget {
             style: Theme.of(context).textTheme.headline,
           ),
           SizedBox(height: 16.0),
-          SizedBox(
+          OnBoardingButton(
-            width: double.infinity,
+            text: "GitHub",
-            child: RaisedButton.icon(
+            iconUrl: 'assets/icon/github-icon.png',
-              label: Text(
-                "GitHub",
-                textAlign: TextAlign.center,
-                style: Theme.of(context).textTheme.button,
-              ),
-              icon: Image.asset(
-                'assets/icon/github-icon.png',
-                width: 32,
-                height: 32,
-              ),
-              color: Theme.of(context).primaryColor,
             onPressed: () async {
               try {
                 await launch("https://github.com/new");
@@ -361,22 +350,10 @@ class OnBoardingCreateRepo extends StatelessWidget {
               onDone();
             },
           ),
-          ),
           SizedBox(height: 8.0),
-          SizedBox(
+          OnBoardingButton(
-            width: double.infinity,
+            text: "GitLab",
-            child: RaisedButton.icon(
+            iconUrl: 'assets/icon/gitlab-icon.png',
-              label: Text(
-                "GitLab",
-                textAlign: TextAlign.center,
-                style: Theme.of(context).textTheme.button,
-              ),
-              icon: Image.asset(
-                'assets/icon/gitlab-icon.png',
-                width: 32,
-                height: 32,
-              ),
-              color: Theme.of(context).primaryColor,
             onPressed: () async {
               try {
                 await launch("https://gitlab.com/projects/new");
@@ -388,7 +365,6 @@ class OnBoardingCreateRepo extends StatelessWidget {
               onDone();
             },
           ),
-          ),
         ],
         mainAxisAlignment: MainAxisAlignment.center,
         crossAxisAlignment: CrossAxisAlignment.start,