The Clintons attended Trump's 2005 wedding, and the mogul donated to Clinton's Senate campaign. So perhaps it's not surprising that he was more positive about Clinton in the not-too-distant past.
"Hillary Clinton I think is a terrific woman," he told Fox News' Greta Van Susteren in March of 2012. "I am biased because I have known her for years. I live in New York. She lives in New York. I really like her and her husband both a lot. I think she really works hard."
I think she really works hard and I think she does a good job. I like her," he added of the then-secretary of state. - Source
That was Donald Trump the businessman in NY.
In order to succeed in business you need to keep politicians on your side. Trump made millions in New York where the political corruption is endemic and a real estate developer needs to keep the politicians happy.
I'm sure Trump said nice things about many politicians in NY.
In running for political office Trump is addressing the issues.
It has cost him money. Macy's and others refused to continue doing business with him. Univision backed out of a contract to air his Miss Universe beauty contest.
But through it all Trump has stuck to his principles.