Butterknife: Cannot add extension with name 'android'

[aelmahdaoui]

The readme says to add the following in the module:

apply plugin: 'com.android.library'
apply plugin: 'com.jakewharton.butterknife'

But if I add it to the already present plugins, i have:

apply plugin: 'com.android.application'
apply plugin: 'com.android.library'
apply plugin: 'com.jakewharton.butterknife'

This however gives me the following error:

Cannot add extension with name 'android', as there is an extension already registered with that name.

[JakeWharton]

apply plugin: 'com.android.application'
apply plugin: 'com.android.library'

add one of these two, not both.

[aelmahdaoui]

Only the one with "application" works, if I try to add only the library, it gives the error:

Error:Library projects cannot set applicationId. applicationId is set to XXX in default config.

[gau4sar]

@JakeWharton I think the README.MD needs to be updated

[franksight]

@JakeWharton I think the README.MD needs to be updated

apply plugin: 'com.android.application'
apply plugin: 'com.android.library'
BECAUSE NOBODY KNOWS add one of these two, not both.