initial app structure

lib/main.dart

@@ -11,7 +11,7 @@ class MyApp extends StatelessWidget {
   @override
   Widget build(BuildContext context) {
     return MaterialApp(
-      title: 'Flutter Demo',
+      title: 'Base Converter',
       theme: ThemeData(
         // This is the theme of your application.
         //
@@ -24,92 +24,176 @@ class MyApp extends StatelessWidget {
         // is not restarted.
         primarySwatch: Colors.blue,
       ),
-      home: const MyHomePage(title: 'Flutter Demo Home Page'),
+      home: const MyHomePage(),
     );
   }
 }
 
 class MyHomePage extends StatefulWidget {
-  const MyHomePage({Key? key, required this.title}) : super(key: key);
+  const MyHomePage({Key? key}) : super(key: key);
-
-  // This widget is the home page of your application. It is stateful, meaning
-  // that it has a State object (defined below) that contains fields that affect
-  // how it looks.
-
-  // This class is the configuration for the state. It holds the values (in this
-  // case the title) provided by the parent (in this case the App widget) and
-  // used by the build method of the State. Fields in a Widget subclass are
-  // always marked "final".
-
-  final String title;
 
   @override
   State<MyHomePage> createState() => _MyHomePageState();
 }
 
 class _MyHomePageState extends State<MyHomePage> {
-  int _counter = 0;
+  String fromBase = "One";
+  String toBase = "One";
 
-  void _incrementCounter() {
+  String result = "";
-    setState(() {
+
-      // This call to setState tells the Flutter framework that something has
+  late TextEditingController _controller;
-      // changed in this State, which causes it to rerun the build method below
+  RichText richText = RichText(text: const TextSpan());
-      // so that the display can reflect the updated values. If we changed
+
-      // _counter without calling setState(), then the build method would not be
+  @override
-      // called again, and so nothing would appear to happen.
+  void initState() {
-      _counter++;
+    super.initState();
-    });
+    _controller = TextEditingController();
   }
 
   @override
   Widget build(BuildContext context) {
-    // This method is rerun every time setState is called, for instance as done
-    // by the _incrementCounter method above.
-    //
-    // The Flutter framework has been optimized to make rerunning build methods
-    // fast, so that you can just rebuild anything that needs updating rather
-    // than having to individually change instances of widgets.
     return Scaffold(
       appBar: AppBar(
-        // Here we take the value from the MyHomePage object that was created by
+        title: const Text("Base Converter"),
-        // the App.build method, and use it to set our appbar title.
+        actions: [
-        title: Text(widget.title),
+          IconButton(
+              onPressed: () => {
+                    showDialog(
+                        context: context,
+                        builder: (BuildContext context) {
+                          return AlertDialog(
+                              title: const Text("How to use:"),
+                              content: const Text(
+                                "Input the number you want to convert, select the base it is in and the base you want convert it into. Then click \"Calculate\" and the result will appear at the bottom of the screen!",
+                                style: TextStyle(fontSize: 13),
+                              ),
+                              contentPadding:
+                                  const EdgeInsets.fromLTRB(24, 16, 24, 8),
+                              actions: [
+                                TextButton(
+                                    onPressed: () => {Navigator.pop(context)},
+                                    child: Row(
+                                        mainAxisAlignment:
+                                            MainAxisAlignment.center,
+                                        children: const [Text("Close")]))
+                              ]);
+                        }),
+                  },
+              icon: const Icon(Icons.info_outline_rounded))
+        ],
       ),
-      body: Center(
+      body: SafeArea(
-        // Center is a layout widget. It takes a single child and positions it
+        child: Container(
-        // in the middle of the parent.
+          margin: const EdgeInsets.fromLTRB(24, 32, 24, 32),
+          child: Column(children: [
+            mainBody(),
+            Expanded(
+              child: Center(child: richText),
+            )
+          ]),
+        ),
+      ),
+    );
+  }
+
+  Container mainBody() {
+    return Container(
+      height: 320,
+      margin: const EdgeInsets.all(0),
+      padding: const EdgeInsets.all(4),
+      child: Center(
         child: Column(
-          // Column is also a layout widget. It takes a list of children and
+          mainAxisAlignment: MainAxisAlignment.spaceEvenly,
-          // arranges them vertically. By default, it sizes itself to fit its
+          crossAxisAlignment: CrossAxisAlignment.center,
-          // children horizontally, and tries to be as tall as its parent.
+          children: [
-          //
+            TextField(
-          // Invoke "debug painting" (press "p" in the console, choose the
+              controller: _controller,
-          // "Toggle Debug Paint" action from the Flutter Inspector in Android
+              decoration: const InputDecoration(hintText: "Number "),
-          // Studio, or the "Toggle Debug Paint" command in Visual Studio Code)
-          // to see the wireframe for each widget.
-          //
-          // Column has various properties to control how it sizes itself and
-          // how it positions its children. Here we use mainAxisAlignment to
-          // center the children vertically; the main axis here is the vertical
-          // axis because Columns are vertical (the cross axis would be
-          // horizontal).
-          mainAxisAlignment: MainAxisAlignment.center,
-          children: <Widget>[
-            const Text(
-              'You have pushed the button this many times:',
-            ),
-            Text(
-              '$_counter',
-              style: Theme.of(context).textTheme.headline4,
             ),
+            Row(mainAxisAlignment: MainAxisAlignment.spaceBetween, children: [
+              baseSelector("From:", fromBase),
+              baseSelector("To:", toBase)
+            ]),
+            Row(children: [
+              Expanded(
+                  child: TextButton(
+                      style: ButtonStyle(
+                          backgroundColor:
+                              MaterialStateProperty.all<Color>(Colors.blue)),
+                      onPressed: calculate,
+                      child: const Text("CALCULATE!",
+                          style: TextStyle(color: Colors.white))))
+            ]),
           ],
         ),
       ),
-      floatingActionButton: FloatingActionButton(
+    );
-        onPressed: _incrementCounter,
+  }
-        tooltip: 'Increment',
+
-        child: const Icon(Icons.add),
+  void calculate() {}
-      ), // This trailing comma makes auto-formatting nicer for build methods.
+
+  void decimalToBase() {}
+
+  void baseToDecimal() {}
+
+  Container baseSelector(String labelText, String value) {
+    return Container(
+      margin: const EdgeInsets.all(4),
+      child: Row(
+        mainAxisAlignment: MainAxisAlignment.center,
+        children: [
+          Text(labelText),
+          const SizedBox(
+            width: 10,
+          ),
+          dpb(value),
+        ],
+      ),
+    );
+  }
+
+  DropdownButton dpb(String dropdownValue) {
+    return DropdownButton<String>(
+      value: dropdownValue,
+      icon: const Icon(Icons.arrow_downward),
+      iconSize: 24,
+      elevation: 16,
+      style: const TextStyle(color: Colors.deepPurple),
+      underline: Container(
+        height: 2,
+        color: Colors.deepPurpleAccent,
+      ),
+      onChanged: (String? newValue) {
+        setState(() {
+          dropdownValue = newValue!;
+        });
+      },
+      items: <String>[
+        'One',
+        'Two',
+        'Three',
+        'Four',
+        'Five',
+        'Six',
+        'Seven',
+        'Eight',
+        'Nine',
+        'Ten',
+        'Eleven',
+        'Twelve',
+        'Thirteen',
+        'Fourteen',
+        'Fifteen',
+        'Hex',
+        'BCD',
+        '2\'s CP'
+      ].map<DropdownMenuItem<String>>((String value) {
+        return DropdownMenuItem<String>(
+          value: value,
+          child: Text(value),
+        );
+      }).toList(),
     );
   }
 }