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ImageReference

public class ImageReference
extends Object implements VersionedParcelable

java.lang.Object
   ↳ androidx.car.cluster.navigation.ImageReference

Reference to an image. This class encapsulates a 'content://' style URI plus metadata that allows consumers to know the image they will receive and how to handle it.

  • Sizing: Producers will always provide an image "original" size which defines the image aspect ratio. When requesting these images, consumers must always specify a desired size (width and height) based on UI available space and the provided aspect ration. Producers can use this "requested" size to select the best version of the requested image, and producers can optionally resize the image to exactly match the "requested" size provided, but consumers should not assume that the received image will match such size. Instead, consumers should always assume that the image will require additional scaling.
  • Content: Producers should avoid including margins around the image content.
  • Format: Content URI must reference a file with MIME type 'image/png', 'image/jpeg' or 'image/bmp' (vector images are not supported).
  • Color: Images can be either "tintable" or not. A "tintable" image is such that all its content is defined in its alpha channel, while its color (all other channels) can be altered without losing information (e.g.: icons). A non "tintable" images contains information in all its channels (e.g.: photos).
  • Caching: Given the same image reference and the same requested size, producers must return the exact same image. This means that it should be safe for the consumer to cache an image once downloaded and use this image reference plus requested size as key, for as long as they need. If a producer needs to provide a different version of a certain image, they must provide a different image reference (e.g. producers can opt to include version information as part of the content URI).

Summary

Nested classes

class ImageReference.Builder

Builder for creating an ImageReference. 

Public methods

boolean equals(Object o)
Uri getContentUri(int width, int height)

Returns a fully formed Uri that can be used to retrieve the actual image, including size constraints, or null if this image reference is not properly formed.

int getOriginalHeight()

Returns the image height, which should only be used to determine the image aspect ratio.

int getOriginalWidth()

Returns the image width, which should only be used to determine the image aspect ratio.

int hashCode()
boolean isTintable()

Returns whether this image is "tintable" or not.

String toString()

Inherited methods

Public methods

equals

public boolean equals (Object o)

Parameters
o Object

Returns
boolean

getContentUri

public Uri getContentUri (int width, 
                int height)

Returns a fully formed Uri that can be used to retrieve the actual image, including size constraints, or null if this image reference is not properly formed.

Producers can optionally use these size constraints to provide an optimized version of the image, but the resulting image might still not match the requested size.

Consumers must confirm the size of the received image and scale it proportionally ( maintaining the aspect ratio of the received image) if it doesn't match the desired dimensions.

Parameters
width int: desired maximum width (must be greater than 0)

Value is between 1 and 2147483647 inclusive.
height int: desired maximum height (must be greater than 0)

Value is between 1 and 2147483647 inclusive.
Returns
Uri fully formed Uri, or null if this image reference can not be used.

getOriginalHeight

public int getOriginalHeight ()

Returns the image height, which should only be used to determine the image aspect ratio.

Returns
int

getOriginalWidth

public int getOriginalWidth ()

Returns the image width, which should only be used to determine the image aspect ratio.

Returns
int

hashCode

public int hashCode ()

Returns
int

isTintable

public boolean isTintable ()

Returns whether this image is "tintable" or not. An image is "tintable" when all its content is defined in its alpha-channel, designed to be colorized (e.g. using PorterDuff.Mode.SRC_ATOP image composition).

Returns
boolean

toString

public String toString ()

Returns
String