Package com.bumptech.glide.load.resource

Class UnitTransformation<T>

  • Type Parameters:
    T - The type of the resource that will always be returned unmodified.
    All Implemented Interfaces:
    Key, Transformation<T>
    public final class UnitTransformation<T>
extends java.lang.Object
implements Transformation<T>
    A no-op Transformation that simply returns the given resource.

    • Method Summary

      All Methods Static Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      static <T> UnitTransformation<T> get()
      Returns a UnitTransformation for the given type.
      Resource<T> transform​(android.content.Context context, Resource<T> resource, int outWidth, int outHeight)
      Transforms the given resource and returns the transformed resource.
      void updateDiskCacheKey​(java.security.MessageDigest messageDigest)
      Adds all uniquely identifying information to the given digest.

      • Methods inherited from class java.lang.Object

        clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

    • Method Detail

      • get

        @NonNull
public static <T> UnitTransformation<T> get()
        Returns a UnitTransformation for the given type.
        Type Parameters:
        T - The type of the resource to be transformed.

      • transform

        @NonNull
public Resource<T> transform​(@NonNull
                             android.content.Context context,
                             @NonNull
                             Resource<T> resource,
                             int outWidth,
                             int outHeight)
        Description copied from interface: Transformation
        Transforms the given resource and returns the transformed resource.

        If the original resource object is not returned, the original resource will be recycled and it's internal resources may be reused. This means it is not safe to rely on the original resource or any internal state of the original resource in any new resource that is created. Usually this shouldn't occur, but if absolutely necessary either the original resource object can be returned with modified internal state, or the data in the original resource can be copied into the transformed resource.

        If a Transformation is updated, Key.equals(Object), Key.hashCode(), and Key.updateDiskCacheKey(java.security.MessageDigest) should all change. If you're using a simple String key an easy way to do this is to append a version number to your key. Failing to do so will mean users may see images loaded from cache that had the old version of the Transformation applied. Changing the return values of those methods will ensure that the cache key has changed and therefore that any cached resources will be re-generated using the updated Transformation.

        During development you may need to either using DiskCacheStrategy.NONE or make sure Key.updateDiskCacheKey(java.security.MessageDigest) changes each time you make a change to the Transformation. Otherwise the resource you request may be loaded from disk cache and your Transformation may not be called.

        Specified by:
        transform in interface Transformation<T>
        Parameters:
        context - The Application context
        resource - The resource to transform.
        outWidth - The width of the view or target the resource will be displayed in, or Target.SIZE_ORIGINAL to indicate the original resource width.
        outHeight - The height of the view or target the resource will be displayed in, or Target.SIZE_ORIGINAL to indicate the original resource height.
        Returns:
        The transformed resource.

      • updateDiskCacheKey

        public void updateDiskCacheKey​(@NonNull
                               java.security.MessageDigest messageDigest)
        Description copied from interface: Key
        Adds all uniquely identifying information to the given digest.

        Note - Using MessageDigest.reset() inside of this method will result in undefined behavior.

        Specified by:
        updateDiskCacheKey in interface Key