Add keyboard shortcuts for usage with BT Pedal

lib/bt_pedal_shortcuts.dart

@@ -0,0 +1,42 @@
+import 'package:flutter/material.dart';
+import 'package:flutter/services.dart';
+
+class BtPedalShortcuts extends StatefulWidget {
+  final Widget child;
+  final VoidCallback? onTurnPageForward;
+  final VoidCallback? onTurnPageBackward;
+
+  const BtPedalShortcuts({
+    super.key,
+    required this.child,
+    this.onTurnPageForward,
+    this.onTurnPageBackward,
+  });
+
+  @override
+  State<BtPedalShortcuts> createState() => _BtPedalShortcutsState();
+}
+
+class _BtPedalShortcutsState extends State<BtPedalShortcuts> {
+  String lastAction = "Press pedal...";
+
+  @override
+  Widget build(BuildContext context) {
+    return CallbackShortcuts(
+      bindings: <ShortcutActivator, VoidCallback>{
+        // Shortcuts for page forward
+        const SingleActivator(LogicalKeyboardKey.arrowUp):
+            widget.onTurnPageForward ?? () => {},
+        const SingleActivator(LogicalKeyboardKey.arrowRight):
+            widget.onTurnPageForward ?? () => {},
+
+        // Shortcuts for page backward
+        const SingleActivator(LogicalKeyboardKey.arrowDown):
+            widget.onTurnPageBackward ?? () => {},
+        const SingleActivator(LogicalKeyboardKey.arrowLeft):
+            widget.onTurnPageBackward ?? () => {},
+      },
+      child: Focus(autofocus: true, child: widget.child),
+    );
+  }
+}

lib/sheet_viewer_page.dart

@@ -5,6 +5,7 @@ import 'package:flutter_drawing_board/flutter_drawing_board.dart';
 import 'package:logging/logging.dart';
 import 'package:pdfrx/pdfrx.dart';
 import 'package:sheetless/api.dart';
+import 'package:sheetless/bt_pedal_shortcuts.dart';
 import 'package:sheetless/sheet.dart';
 import 'package:sheetless/storage_helper.dart';
 
@@ -86,9 +87,19 @@ class _SheetViewerPageState extends State<SheetViewerPage> {
     }
   }
 
+  void turnPage(int numTurns) {
+    setState(() {
+      page += numTurns;
+      page = page.clamp(1, numPages);
+    });
+  }
+
   @override
   Widget build(BuildContext context) {
-    return Scaffold(
+    return BtPedalShortcuts(
+      onTurnPageForward: () => turnPage(1),
+      onTurnPageBackward: () => turnPage(-1),
+      child: Scaffold(
         appBar: AppBar(
           title: Text(widget.sheet.name),
           actions: [
@@ -136,7 +147,9 @@ class _SheetViewerPageState extends State<SheetViewerPage> {
                         child: GestureDetector(
                           onTapUp: (TapUpDetails details) {
                             // Get the size of the screen
-                          final screenWidth = MediaQuery.of(context).size.width;
+                            final screenWidth = MediaQuery.of(
+                              context,
+                            ).size.width;
 
                             // print("Touch at y = ${details.localPosition.dy}");
                             // print("Touch at x = ${details.localPosition.dx}");
@@ -149,14 +162,10 @@ class _SheetViewerPageState extends State<SheetViewerPage> {
                             // });
                             if (details.localPosition.dx < screenWidth / 2) {
                               // Left half of the screen
-                            setState(() {
-                              page = page > 1 ? page - 1 : 1;
-                            });
+                              turnPage(-1);
                             } else {
                               // Right half of the screen
-                            setState(() {
-                              page = page < numPages ? page + 1 : numPages;
-                            });
+                              turnPage(1);
                             }
                           },
                           child: Row(
@@ -203,7 +212,9 @@ class _SheetViewerPageState extends State<SheetViewerPage> {
                                         child: Container(
                                           alignment: Alignment.bottomCenter,
                                           padding: EdgeInsets.only(bottom: 5),
-                                        child: Text('${page + 1} / $numPages'),
+                                          child: Text(
+                                            '${page + 1} / $numPages',
+                                          ),
                                         ),
                                       ),
                                     ],
@@ -273,6 +284,7 @@ class _SheetViewerPageState extends State<SheetViewerPage> {
             }
           },
         ),
+      ),
     );
   }