After you've manipulated the image you need to write the new image back to the Blobstore using an HTTP multi-part/formdata POST. You can do this with the URLFetchService.
I do this on my site and have just put a new blog entry up about it here: http://jeremyblythe.blogspot.com/2010/10/manipulating-images-in-blobstore.html <http://jeremyblythe.blogspot.com/2010/10/manipulating-images-in-blobstore.html> J. On Fri, Oct 15, 2010 at 8:44 PM, davisnog <[email protected]> wrote: > I got this example from the site: > http://code.google.com/intl/en/appengine/docs/java/images/overview.html > > I'm using the API in this way: > BlobKey blobKey = blobs.get("image"); > > ImagesService imagesService = > ImagesServiceFactory.getImagesService(); > Image oldImage = > ImagesServiceFactory.makeImageFromBlob(blobKey); > Transform resize = ImagesServiceFactory.makeResize(200, > 300); > > Image newImage = imagesService.applyTransform(resize, > oldImage); > > > String urlimg = images.getServingUrl(newImage.getBlobKey()); > > my .jsp > > <img src ="urlimg" /> > > > when I invoke the method: > > images.getServingUrl(newImage.getBlobKey()); > > newImage.getBlobKey() is always null. > > I'm looking to manipulate the image and then return the image url. > > How could I be doing? > > -- > You received this message because you are subscribed to the Google Groups > "Google App Engine for Java" group. > To post to this group, send email to > [email protected]. > To unsubscribe from this group, send email to > [email protected]<google-appengine-java%[email protected]> > . > For more options, visit this group at > http://groups.google.com/group/google-appengine-java?hl=en. > > -- You received this message because you are subscribed to the Google Groups "Google App Engine for Java" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/google-appengine-java?hl=en.
