📏 dimensions_theme

dimensions_theme provides a theme extension to easily define and access app dimensions such as blank spaces, padding, border radius, and other dimensions within the Flutter theme.

Define your dimensions

// Uses tokens that best fit your project needs. You can also use multiple enums
enum Dimension {
  xlarge,
  large,
  medium,
  small,
  xsmall,
}

...

MaterialApp(
  theme: ThemeData(
    extensions: const [
      DimensionsTheme({
        Dimension.xlarge: 20,
        Dimension.large: 16,
        Dimension.medium: 12,
        Dimension.small: 8,
        Dimension.xsmall: 4,
      }),
    ],
  ),
);

Uses multiple enum for dimensions

The Dimensions theme extension supports using multiple enums as dimension tokens. This can be useful if you want to give different kinds of dimensions value their own enum.

enum Space {
  xlarge,
  large,
  medium,
  small,
  xsmall,
}

enum Padding {
  xlarge,
  large,
  medium,
  small,
  xsmall,

  screen,
}

...

MaterialApp(
  theme: ThemeData(
    extensions: const [
      DimensionsTheme({
        Space.xlarge: 20,
        Space.large: 16,
        Space.medium: 12,
        Space.small: 8,
        Space.xsmall: 4,

        Padding.xlarge: 20,
        Padding.large: 16,
        Padding.medium: 12,
        Padding.small: 8,
        Padding.xsmall: 4,
        Padding.screen: 20,
      }),
    ],
  ),
);

Consume dimensions values

You can access any dimension value using the get:

Dimensions.of(context).get(Dimension.small);

Additionally, this package provides helpers to make it easier to work with defined dimensions.

Padding

The padding context extension constructs EdgeInsets using the values defined in the dimensions theme for a given dimension token.

Padding(
  padding: context.padding.all(Dimension.small)
  child: ...
)

This extension provides counterparts to all EdgeInsets constructors but uses Dimension tokens instead of raw double values.

context.padding.all(Dimension.small)

context.padding.symmetric(
  horizontal: Dimension.medium,
  vertical: Dimensions.small,
)

context.padding.only(
  left: Dimension.large
  top: Dimension.large,
)

Blank spaces

The Space widget creates a SizedBox with the values defined in the dimensions theme for a given dimension token.

Column(
  children: [
    SomeWidget(),
    Space(Dimensions.small),
    SomeWidget(),
  ]
)

Alternatively, you can use the SpaceDimensionsMixin to construct Space widgets directly from your tokens:

/// Add `SpaceDimensionsMixin` to your dimension token responsible for spaces
enum Spaces with SpaceDimensionsMixin {
  large,
  medium
  small,
}

...

Column(
  children: [
    SomeWidget(),
    Spaces.small(),
    SomeWidget(),
  ]
)

All space widgets come with .w and .h constructors to restrict the blank space in one axis, respectively width and height.

Space.h(Dimensions.small)
Space.w(Dimensions.small)

Spaces.small.h()
Spaces.small.w()

Border radius

The radius context extension constructs Radius using the values defined in the dimensions theme for a given dimension token.

Container(
  decoration: BoxDecoration(
    borderRadius: BorderRadius.all(
      context.radius.circular(Dimensions.large),
    ),
  ),
)

This extension provides counterparts to all Radius constructors but uses Dimension tokens instead of raw double values.

context.radius.elliptical(Dimensions.large);
context.radius.circular(Dimensions.small, Dimensions.large);

The extension also provides a counterpart to BorderRadius.circular().

Container(
  decoration: BoxDecoration(
    borderRadius: borderRadius.circular(Dimensions.large),
  ),
)