Initial commit

lib/widgets/play_pause_button.dart

@@ -0,0 +1,42 @@
+import 'package:flutter/material.dart';
+
+import '../backend.dart';
+
+class PlayPauseButton extends StatefulWidget {
+  @override
+  _PlayPauseButtonState createState() => _PlayPauseButtonState();
+}
+
+class _PlayPauseButtonState extends State<PlayPauseButton>
+    with SingleTickerProviderStateMixin {
+  AnimationController playPauseAnimation;
+  Backend backend;
+
+  @override
+  void initState() {
+    super.initState();
+
+    playPauseAnimation =
+        AnimationController(vsync: this, duration: Duration(milliseconds: 300));
+  }
+
+  @override
+  void didChangeDependencies() {
+    super.didChangeDependencies();
+
+    backend = Backend.of(context);
+    backend.playing.listen((playing) =>
+        playing ? playPauseAnimation.forward() : playPauseAnimation.reverse());
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    return IconButton(
+      icon: AnimatedIcon(
+        icon: AnimatedIcons.play_pause,
+        progress: playPauseAnimation,
+      ),
+      onPressed: backend.playPause,
+    );
+  }
+}

lib/widgets/player_bar.dart

@@ -0,0 +1,56 @@
+import 'package:flutter/material.dart';
+
+import '../backend.dart';
+import '../screens/program.dart';
+
+import 'play_pause_button.dart';
+
+class PlayerBar extends StatelessWidget {
+  @override
+  Widget build(BuildContext context) {
+    final backend = Backend.of(context);
+
+    return BottomAppBar(
+      child: InkWell(
+        child: Column(
+          mainAxisSize: MainAxisSize.min,
+          children: <Widget>[
+            StreamBuilder(
+              stream: backend.position,
+              builder: (context, snapshot) => LinearProgressIndicator(
+                value: snapshot.data,
+              ),
+            ),
+            Row(
+              children: <Widget>[
+                Padding(
+                  padding: const EdgeInsets.all(8.0),
+                  child: Icon(Icons.keyboard_arrow_up),
+                ),
+                Expanded(
+                  child: Column(
+                    crossAxisAlignment: CrossAxisAlignment.start,
+                    children: <Widget>[
+                      Text(
+                        'Composer',
+                        style: TextStyle(fontWeight: FontWeight.bold),
+                      ),
+                      Text('Work: Movement'),
+                    ],
+                  ),
+                ),
+                PlayPauseButton(),
+              ],
+            ),
+          ],
+        ),
+        onTap: () => Navigator.push(
+          context,
+          MaterialPageRoute(
+            builder: (context) => ProgramScreen(),
+          ),
+        ),
+      ),
+    );
+  }
+}