Flex Builder4.5 automatic import package

Open "Preferences" >> Flash Builder >> Editor, find Code Assist, tick "Use Other Custom Triggers", and enter:
abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ_After

setting the above, after entering the first one or two characters, Select Enter in the automatic prompt to automatically import the corresponding package.