CameraKit (Support Gallery Picker)
· Provides an implementation of the CameraKit MediaProcessor Source which uses Android Intents to pick media from local storage.
Download JD-GUI to open JAR file and explore Java source code file (.class .java)
Click menu "File → Open File..." or just drag-and-drop the JAR file in the JD-GUI window support-gallery-picker-1.25.0.jar file.
Once you open a JAR file, all the java classes in the JAR file will be displayed.