He does need 1237 delegates to get the nomination, but the delegates of both Trump and Cruz could come together and give him the delegates he needs. That however does not mean that he will get the necessary 270 electoral votes to win the election.
You know the rats will do anything to get Hillary Rotten Clinton to be the next president, because it's her time and she "deserves" to be president.
That however does not mean that he will get the necessary 270 electoral votes to win the election. Getting the delegates is, however, a necessary prerequisite towards getting the votes in the electoral college.