I have generated a graph. On click of each bar in the graph, I should be able to generate another graph. I am using GD::Graph module. If its not possible to make the bars clickable, is there a way where I can click the x-axis values at least? Thank you.
If you want user interaction, I believe you need to work with a GUI toolkit such as Prima (CPAN link), Gtk2 (CPAN link), or something else. (Note the Qt bindings are old and I am not sure they work these days.) For exampe, I don't think it would be too difficult to create an image file with GD::Graph and then load it into Prima. You'd have to write your own MouseDown routines, which might go beyond your skill or interest, but I think this is the only way (currently) to do it.
If you are making a non-browser GUI then David has you covered.