Logisim Flashing button
Build an edge detector. It can as simple as this:



Since Logisim doesn't have a monoflop you need to use the clock generator to generate time events. The D-FF stores the level of your input. ANDing the input with the inverted delayed input gives you a short pulse each time you raise the level from 0 to 1.

This pulse has varying duration depending when the input raising edge happens in respect to the clock edge. If you need a pulse of equal duration synchronize the input with another D-FF before feeding it into this circuit.