WIP - Initial prototyping of positioned widgets

stevia/lib/src/services/text_input_formatters.dart

@@ -28,23 +28,24 @@ class IntTextInputFormatter extends TextInputFormatter {
 
   @override
   TextEditingValue formatEditUpdate(TextEditingValue oldValue, TextEditingValue newValue) {
-    if (newValue.text.isEmpty || newValue.text == '-') {
+    final TextEditingValue(:text, :selection, :composing) = newValue;
+    if (text.isEmpty || text == '-') {
       return newValue;
     }
 
-    final trimmed = newValue.text.trim().replaceAll(',', '');
+    final trimmed = text.trim().replaceAll(',', '');
     return switch (int.tryParse(trimmed)) {
-      final value? when _range.contains(value) => switch (newValue.text.length == trimmed.length) {
+      final value? when _range.contains(value) => switch (text.length == trimmed.length) {
         true => newValue,
         false => TextEditingValue(
           text: trimmed,
-          selection: newValue.selection.copyWith(
-            baseOffset: math.min(newValue.selection.start, trimmed.length),
-            extentOffset: math.min(newValue.selection.end, trimmed.length),
+          selection: selection.copyWith(
+            baseOffset: math.min(selection.start, trimmed.length),
+            extentOffset: math.min(selection.end, trimmed.length),
           ),
-          composing: !newValue.composing.isCollapsed && trimmed.length > newValue.composing.start ? TextRange(
-            start: newValue.composing.start,
-            end: math.min(newValue.composing.end, trimmed.length),
+          composing: !composing.isCollapsed && trimmed.length > composing.start ? TextRange(
+            start: composing.start,
+            end: math.min(composing.end, trimmed.length),
           ): TextRange.empty,
         )
       },

stevia/lib/src/widgets/positioned/positioned_route.dart

@@ -0,0 +1,29 @@
+import 'package:flutter/cupertino.dart';
+import 'package:meta/meta.dart';
+
+class PositionedRoute extends PopupRoute<void> {
+
+  @override
+  final Color? barrierColor;
+  @override
+  final String? barrierLabel;
+  @override
+  final bool barrierDismissible;
+  @override
+  final Duration transitionDuration;
+
+  /// Creates a [PositionedRoute].
+  PositionedRoute({
+    this.barrierLabel,
+    this.barrierColor,
+    this.barrierDismissible = true,
+    this.transitionDuration = const Duration(milliseconds: 300),
+  });
+
+  @override
+  Widget buildPage(BuildContext context, Animation<double> animation, Animation<double> secondaryAnimation) {
+    // TODO: implement buildPage
+    throw UnimplementedError();
+  }
+
+}

stevia/lib/src/widgets/resizable/resizable_box.dart

@@ -9,7 +9,7 @@ import 'package:stevia/src/widgets/resizable/resizable_region_change_notifier.da
 
 /// A box which children can all be resized either horizontally or vertically.
 ///
-/// Each child must be selected by tapping on it before it can be resized.
+/// Each child is a [ResizableRegion] that must be selected by tapping on it before it can be resized.
 ///
 /// ## Contract
 /// Each child has a minimum size determined by its slider size multiplied by 2. Setting an initial size smaller