Check if the current instance of SubsamplingScaleImageView has an image set

[laurencedawson]

It would be quite handy to see at a glance if the view has an image set.

I'm doing this by checking if the uri is set or the view has has a bitmap set.

[davemorrissey]

Looks okay, but under what circumstances do you not know whether setImage has been called?

[laurencedawson]

I'm displaying a series of posts in a ViewPager, some images and some text.

As a user scrolls through the pager, they can trigger cursor updates which then invalidates each Fragment in the pager. When this update comes in I want to quickly check if the Fragment has already requested an image or has previously set the image. I handle the image management myself but it seems redundant to store a flag in the fragment to say it's set the image when the information is available in the view itself.

[davemorrissey]

Yeah that makes sense. I'm finishing off a change to zoom behaviour (#148) and will merge this when I'm done - but I'll rename it hasImage.