ButtonStatePropertyDelegate<T> typedef

ButtonStatePropertyDelegate<T> = T Function(BuildContext context, Set<WidgetState> states, T value)

Function signature for button state property delegates with default value.

ButtonStatePropertyDelegate extends ButtonStateProperty by adding a value parameter representing the default or base value. This allows delegates to modify existing values rather than always creating them from scratch.

The delegate receives:

• context: Build context for accessing theme data
• states: Current widget states
• value: The default value from the base style

Returns the final property value of type T, which may be the default value, a modified version of it, or a completely new value.

Example:

ButtonStatePropertyDelegate<Color> customColor = (context, states, defaultColor) {
  if (states.contains(WidgetState.disabled)) {
    return defaultColor.withOpacity(0.5); // Modify default
  }
  return defaultColor; // Use default
};

Implementation

typedef ButtonStatePropertyDelegate<T> = T Function(
    BuildContext context, Set<WidgetState> states, T value);