Hi All, I am working on project using Qt(IDE), C++(language) and opencv libraries. The board I am using is Olimex Olinux A64. In the project I have a GUI that displays the input from a camera and has various status indicator labels. These labels indicate various states the system is in at any particular instance of time. I load different images in the labels to indicate different states. As of now the trigger to change the image of a label comes from soft buttons written in c++ using the Qt buttons layout. I am trying to find a way to control the change of images in the labels using hardware buttons that are connected to the GPIOs of the A64 board. Could anyone point me in the right direction? Please fell free to comment if my query seems unclear. Any help is much appreciated. Thanks in advance..