Nate Wilson db80f4e713
WidgetState mapping (#146043)
This pull request implements [enhanced enum](https://dart.dev/language/enums#declaring-enhanced-enums) features for the new `WidgetState` enum, in order to improve the developer experience when creating and using `WidgetStateProperty` objects.

`WidgetState` now has a `.matchesSet()` method:

```dart
// identical to "states.contains(WidgetState.error)"
final bool hasError = WidgetState.error.isSatisfiedBy(states);
```

This addition allows for wide variety of `WidgetStateProperty` objects to be constructed in a simple manner.

<br><br>

```dart
// before
final style = MaterialStateTextStyle.resolveWith((states) {
  if (states.contains(MaterialState.error)) {
    return TextStyle(color: Colors.red);
  } else if (states.contains(MaterialState.focused)) {
    return TextStyle(color: Colors.blue);
  }
  return TextStyle(color: Colors.black);
});

// after
final style = WidgetStateTextStyle.fromMap({
  WidgetState.error:   TextStyle(color: Colors.red),
  WidgetState.focused: TextStyle(color: Colors.blue),
  WidgetState.any:     TextStyle(color: Colors.black), // "any" is a static const member, not an enum value
});
```

```dart
// before
final color = MaterialStateProperty.resolveWith((states) {
  if (states.contains(MaterialState.focused)) {
    return Colors.blue;
  } else if (!states.contains(MaterialState.disabled)) {
    return Colors.black;
  }
  return null;
});

// after
final color = WidgetStateProperty<Color?>.fromMap({
  WidgetState.focused:   Colors.blue,
  ~WidgetState.disabled: Colors.black,
});
```

```dart
// before
const activeStates = [MaterialState.selected, MaterialState.focused, MaterialState.scrolledUnder];

final color = MaterialStateColor.resolveWith((states) {
  if (activeStates.any(states.contains)) {
    if (states.contains(MaterialState.hovered) {
      return Colors.blueAccent;
    }
    return Colors.blue;
  }
  return Colors.black;
});

// after
final active = WidgetState.selected | WidgetState.focused | WidgetState.scrolledUnder;

final color = WidgetStateColor.fromMap({
  active & WidgetState.hovered: Colors.blueAccent,
  active:  Colors.blue,
  ~active: Colors.black,
});
```

<br>

(fixes #146042, and also fixes #143488)
2024-07-18 16:48:06 +00:00
..
2024-03-24 18:01:17 +00:00
2024-01-10 00:17:33 +00:00
2024-06-06 11:33:27 -07:00