God has always used dreams to warn His people of things to come or to give them direction. He even used dreams to warn some unbelievers of things to come. For instance, God warned Pharaoh of a coming famine that would be so terrible it would devour everything from a 7 year period of abundance. He also showed Nebuchadnezzar the progression of world dominating kingdoms that would culminate with second coming of the Messiah to set up His everlasting kingdom (Daniel 2).
In the New Testament, God told Joseph in a dream to go ahead and take Mary as his wife "... for that which is conceived in her is of the Holy Ghost" (Matt. 1:20). God also used dreams to warn the wise men not to return to Herod and to tell Joseph to take the child Jesus to Egypt for safety. And in Acts 13, God used a dream to give Paul specific direction where he should go preach the gospel.
The book of Acts also has Peter's sermon on the day of Pentecost where he quotes the prophet Joel about the last days: