Just learning presents, small white one, now run into A problem, the page is divided into two components, A and B is actually two div,
When A component in A drop-down box value change, B component inside an area to brush the data again,

I now method is introduced in A component B component, ts drop-down box in A component event inside call the refresh method B component,
After the operation, found in component B ts can output the refreshed in the log data, but the page said, the data is not represented,
Excuse me, is what reason, how to solve, thank you very much