By now I am sure the Chinese side won't have any unrealistic expectation that once a US leader visits China, the relations will improve.
The two countries are locking horns in a fight that will determine the fate of China and the US. The fight won't end until one country emerges victorious. And I am sure that country is the United States of America.
These high-level visits are necessary so that the rivalry does not lead to a hot war or even a nuclear war.