public abstract class BitmapTransformation extends Object implements Transformation<Bitmap>
Transformation
for transforming Bitmap
s that
abstracts away dealing with Resource
objects for subclasses.
Use cases will look something like this:
public class FillSpace extends BaseBitmapTransformation {
@Override
public Bitmap transform(BitmapPool pool, Bitmap toTransform, int outWidth, int outHeight) {
if (toTransform.getWidth() == outWidth && toTransform.getHeight() == outHeight) {
return toTransform;
}
return Bitmap.createScaledBitmap(toTransform, outWidth, outHeight, true);
}
}
Constructor and Description |
---|
BitmapTransformation(BitmapPool bitmapPool) |
BitmapTransformation(Context context) |
Modifier and Type | Method and Description |
---|---|
protected abstract Bitmap |
transform(BitmapPool pool,
Bitmap toTransform,
int outWidth,
int outHeight)
Transforms the given
Bitmap based on the given dimensions and returns the transformed
result. |
Resource<Bitmap> |
transform(Resource<Bitmap> resource,
int outWidth,
int outHeight)
Transforms the given resource and returns the transformed resource.
|
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
getId
public BitmapTransformation(Context context)
public BitmapTransformation(BitmapPool bitmapPool)
public final Resource<Bitmap> transform(Resource<Bitmap> resource, int outWidth, int outHeight)
Transformation
Note - 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.
transform
in interface Transformation<Bitmap>
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.protected abstract Bitmap transform(BitmapPool pool, Bitmap toTransform, int outWidth, int outHeight)
Bitmap
based on the given dimensions and returns the transformed
result.
The provided Bitmap, toTransform, should not be recycled or returned to the pool. Glide will automatically recycle and/or reuse toTransform if the transformation returns a different Bitmap. Similarly implementations should never recycle or return Bitmaps that are returned as the result of this method. Recycling or returning the provided and/or the returned Bitmap to the pool will lead to a variety of runtime exceptions and drawing errors. See #408 for an example. If the implementation obtains and discards intermediate Bitmaps, they may safely be returned to the BitmapPool and/or recycled.
outWidth and outHeight will never be Target.SIZE_ORIGINAL
, this
class converts them to be the size of the Bitmap we're going to transform before calling this method.
pool
- A BitmapPool
that can be used to obtain and
return intermediate Bitmap
s used in this transformation. For every
Bitmap
obtained from the pool during this transformation, a
Bitmap
must also be returned.toTransform
- The Bitmap
to transform.outWidth
- The ideal width of the transformed bitmap (the transformed width does not need to match exactly).outHeight
- The ideal height of the transformed bitmap (the transformed heightdoes not need to match
exactly).