ResizeImagePolicy enum

Configures the behavior for ResizeImage.

This is used in ResizeImage.policy to affect how the ResizeImage.width and ResizeImage.height properties are interpreted.

Inheritance

Constructors

ResizeImagePolicy()
const

Values

exact → const ResizeImagePolicy

Sizes the image to the exact width and height specified by ResizeImage.width and ResizeImage.height.

If ResizeImage.width and ResizeImage.height are both non-null, the output image will have the specified width and height (with the corresponding aspect ratio) regardless of whether it matches the source image's intrinsic aspect ratio. This case is similar to BoxFit.fill.

If only one of width and height is non-null, then the output image will be scaled to the associated width or height, and the other dimension will take whatever value is needed to maintain the image's original aspect ratio. These cases are simnilar to BoxFit.fitWidth and BoxFit.fitHeight, respectively.

If ResizeImage.allowUpscaling is false (the default), the width and the height of the output image will each be clamped to the intrinsic width and height of the image. This may result in a different aspect ratio than the aspect ratio specified by the target width and height (e.g. if the height gets clamped downwards but the width does not).

Examples

The examples below show how ResizeImagePolicy.exact works in various scenarios. In each example, the source image has a size of 300x200 (landscape orientation), the red box is a 150x150 square, and the green box is a 400x400 square.

Scenario Output 
const ResizeImage(
  AssetImage('dragon_cake.jpg'),
  width: 150,
  height: 150,
)


const ResizeImage(
  AssetImage('dragon_cake.jpg'),
  width: 150,
)


const ResizeImage(
  AssetImage('dragon_cake.jpg'),
  height: 150,
)


const ResizeImage(
  AssetImage('dragon_cake.jpg'),
  width: 400,
  height: 400,
)


const ResizeImage(
  AssetImage('dragon_cake.jpg'),
  width: 400,
)


const ResizeImage(
  AssetImage('dragon_cake.jpg'),
  height: 400,
)


const ResizeImage(
  AssetImage('dragon_cake.jpg'),
  width: 400,
  height: 400,
  allowUpscaling: true,
)


const ResizeImage(
  AssetImage('dragon_cake.jpg'),
  width: 400,
  allowUpscaling: true,
)


const ResizeImage(
  AssetImage('dragon_cake.jpg'),
  height: 400,
  allowUpscaling: true,
)

fit → const ResizeImagePolicy

Scales the image as necessary to ensure that it fits within the bounding box specified by ResizeImage.width and ResizeImage.height while maintaining its aspect ratio.

If ResizeImage.allowUpscaling is true, the image will be scaled up or down to best fit the bounding box; otherwise it will only ever be scaled down.

This is conceptually similar to BoxFit.contain.

Examples

The examples below show how ResizeImagePolicy.fit works in various scenarios. In each example, the source image has a size of 300x200 (landscape orientation), the red box is a 150x150 square, and the green box is a 400x400 square.

Scenario Output 
const ResizeImage(
  AssetImage('dragon_cake.jpg'),
  policy: ResizeImagePolicy.fit,
  width: 150,
  height: 150,
)


const ResizeImage(
  AssetImage('dragon_cake.jpg'),
  policy: ResizeImagePolicy.fit,
  width: 150,
)


const ResizeImage(
  AssetImage('dragon_cake.jpg'),
  policy: ResizeImagePolicy.fit,
  height: 150,
)


const ResizeImage(
  AssetImage('dragon_cake.jpg'),
  policy: ResizeImagePolicy.fit,
  width: 400,
  height: 400,
)


const ResizeImage(
  AssetImage('dragon_cake.jpg'),
  policy: ResizeImagePolicy.fit,
  width: 400,
)


const ResizeImage(
  AssetImage('dragon_cake.jpg'),
  policy: ResizeImagePolicy.fit,
  height: 400,
)


const ResizeImage(
  AssetImage('dragon_cake.jpg'),
  policy: ResizeImagePolicy.fit,
  width: 400,
  height: 400,
  allowUpscaling: true,
)


const ResizeImage(
  AssetImage('dragon_cake.jpg'),
  policy: ResizeImagePolicy.fit,
  width: 400,
  allowUpscaling: true,
)


const ResizeImage(
  AssetImage('dragon_cake.jpg'),
  policy: ResizeImagePolicy.fit,
  height: 400,
  allowUpscaling: true,
)

Properties

hashCode → int
The hash code for this object.
no setterinherited
index → int
A numeric identifier for the enumerated value.
no setterinherited
runtimeType → Type
A representation of the runtime type of the object.
no setterinherited

Methods

noSuchMethod(Invocation invocation) → dynamic
Invoked when a nonexistent method or property is accessed.
inherited
toString() → String
A string representation of this object.
inherited

Operators

operator ==(Object other) → bool
The equality operator.
inherited

Constants

values → const List<ResizeImagePolicy>
A constant List of the values in this enum, in order of their declaration.