android create common libraries

how do we create common libraries in android that can be used across applications? I want to write some classes which are accessible by all applications. Thank开发者_运维知识库s in advance.

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If you are using Eclipse, Go to Project Properties --> Android . Select 'Is Library' checkbox. That is it.

To use this in other projects, Select Project Properties (of the other project --> Android--> Add (underneath the 'Is Library' checkbox) and select the library)

more instructions here http://developer.android.com/guide/developing/projects/projects-eclipse.html#SettingUpLibraryProject