The evolution of firearms from something like a simple hand-cannon to something light enough to be portable, able to be aimed, and supplied with an ignition system that enabled it to be set off with the pull of a trigger took some time: as did the working out of how to make gunpowder that was effective, did not separate during transport into is component parts, and was somewhat consistent in how it worked ( consider, before knowledge of actual chemistry, how much trial and error must have been required to figure out that dirt from under the latrines of taverns selling wine was better for mining for saltpeter than dirt from taverns that sold beer). But by the end of the 15th c. it was mostly complete. Emperor Maximilian I even had rifles for hunting. The most characteristic weapon of mid-to-late 15th c. Europe was the polearm, whether in the hands of a Swiss halberdier or an English pikeman or billman. Soldiers with arquebuses began to play a bigger and bigger part- certainly in the Italian Wars between the Holy Roman Empire and France. If you wanted to find a tipping-point, after which you could say that firearms were indispensable, perhaps a good one would be the Battle of Pavia in 1525, where Spanish arquebuses were decisive.

But pikes were still important for close fighting, defense of infantry against cavalry, and both pikes and guns would continue to be used well into the 17th c. You could say that, really, pikes just continued to be used: the pikemen and the musketeers were eventually combined into one, when bayonets became more and more common in the later 17th c. As the socket bayonet- that allowed the gun to fire as well as be used as a pike- came into general use at the very end of the 17th c., perhaps you could call that the end of pikemen- the musket no longer had to be converted into just a pike, but could be used always as a musket.