public float getMaximumScale() {
        return attacher.getMaximumScale();
    }
Get the current {@link PhotoViewAttacher} for this view. Be wary of holding on to references
to this attacher, as it has a reference to this view, which, if a reference is held in the
wrong place, can cause memory leaks.

@return the attacher.
main/src/main/java/com/quxianggif/common/view/photoview/PhotoView.java