How to import the jar package correctly when importing third-party jar packages on android

When zxing. jar package is imported on android, an error is always reported:

Cocould not find class 'com. google. zxing. multiformatwrite', referenced from method com. changyang. app. util. Encode2dUtil. creat2DCode

Then I found the solution.:

Before adt17, you must create a lib directory and add to buiild path when importing third-party jar packages.

After adt17, to import a third-party jar package, you must create a libs directory. You cannot use lib to name the package. adt will automatically set the jar dependency. You do not need to add it manually.