You pass reference to activity (context) to static variable [activity](https://github.com/lawloretienne/ImageGallery/blob/master/sample/src/main/java/com/etiennelawlor/imagegallery/activities/MainActivity.java#L79) [static variable](https://github.com/lawloretienne/ImageGallery/blob/master/library/src/main/java/com/etiennelawlor/imagegallery/library/activities/FullScreenImageGalleryActivity.java#L34)
You pass reference to activity (context) to static variable
activity
static variable