docs: Add dot shorthands guide to Flutter concepts (#13180)

Adds a guide on Dart shorthands to the flutter docs.


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Author: lamek

src/content/ui/dot-shorthands.md

@@ -0,0 +1,121 @@
+---
+title: "Dot shorthands in Flutter"
+description: "Learn how to use Dart's dot shorthands to write cleaner, concise Flutter code."
+---
+
+The **dot shorthands** feature allows you to omit the explicit type when
+accessing static members, constructors, or enum values, provided the compiler
+can infer the type from the surrounding context.
+
+:::note
+For a technical overview of this feature, refer to the
+[Dot Shorthands guide](https://dart.dev/language/dot-shorthand) in the Dart
+documentation.
+:::
+
+## Why dot shorthands matter
+
+Building layouts in Flutter often involves deeply nested widget trees.
+Historically, this meant repeatedly typing explicit class and enum names for
+properties like colors, typography, and alignment. Dot shorthands reduces this
+boilerplate, making your code easier to read and faster to write.
+
+Here is a side-by-side comparison of building a simple `Container`:
+
+### Without dot shorthands
+```dart
+Container(
+  alignment: Alignment.center,
+  padding: const EdgeInsets.all(16.0),
+  child: Column(
+    mainAxisAlignment: MainAxisAlignment.center,
+    crossAxisAlignment: CrossAxisAlignment.start,
+    children: [
+      Text(
+        'Hello World',
+        style: TextStyle(
+          fontWeight: FontWeight.bold,
+        ),
+      ),
+    ],
+  ),
+);
+```
+
+### With dot shorthands
+```dart
+Container(
+  alignment: .center, // Instead of Alignment.center,
+  padding: const .all(16.0), // Instead of EdgeInsets.all(16.0)
+  child: Column(
+    mainAxisAlignment: .center, // Instead of MainAxisAlignment.center
+    crossAxisAlignment: .start, // Instead of CrossAxisAlignment.start
+    children: [
+      Text(
+        'Hello World',
+        style: TextStyle(
+          fontWeight: .bold, // Instead of FontWeight.bold
+        ),
+      ),
+    ],
+  ),
+);
+```
+
+## Where to use dot shorthands
+
+Dot shorthands work anywhere the Dart compiler has a clear "context type",
+meaning it knows exactly what type it expects. In Flutter, this is almost
+everywhere inside a widget's property list. 
+
+The most common targets for dot shorthands in Flutter are:
+
+*   **Enums**: `MainAxisAlignment`, `CrossAxisAlignment`, `BoxFit`, `TextDirection`.
+*   **Static properties and methods**: `FontWeight` (constants like `.bold`). 
+*   **Constructors**: `EdgeInsets.all()`, `BorderRadius.circular()`.
+
+### Example: enums
+
+When a property expects an `enum`, such as `mainAxisAlignment`, you can omit the
+enum's name and just provide the value preceded by a dot (`.`):
+
+```dart
+Row(
+  mainAxisAlignment: .spaceEvenly, // Infers MainAxisAlignment.spaceEvenly
+  children: [ /* ... */ ],
+)
+```
+
+### Example: static properties
+
+Static properties work when the context type is exactly the class that defines the property. A common example is text styling with `FontWeight`:
+
+```dart
+Text(
+  'Feature highlights',
+  style: TextStyle(
+    fontWeight: .bold, // Infers FontWeight.bold
+  ),
+)
+```
+
+### Example: constructors
+
+You can also use dot shorthands for named constructors. Many Flutter layout properties accept a base class like `EdgeInsetsGeometry`. To support dot shorthands, Flutter adds redirecting constructors to these base classes that point to the appropriate subclasses.
+
+```dart
+Padding(
+  padding: .symmetric(horizontal: 16.0, vertical: 8.0), // Infers EdgeInsetsGeometry.symmetric
+  child: Text('Spaced out text'),
+)
+```
+
+You can even use `.new` to call an unnamed constructor, though this is less
+common in standard widget trees:
+
+```dart
+class _MyState extends State<MyWidget> {
+  final ScrollController _scrollController = .new(); // Infers ScrollController()
+  // ...
+}
+```

src/data/sidenav.yml

@@ -757,6 +757,8 @@
       permalink: /testing/build-modes
     - title: Hot reload
       permalink: /tools/hot-reload
+    - title: Dot shorthands
+      permalink: /ui/dot-shorthands
 
 - title: App solutions
   icon: apps