今天在打包时候发现了一个奇怪的问题。一个同事使用的较低版本的AS，我使用了当前最新的AS版本3.3.2。去编译，运行他的项目没有任何问题。但是当准备打包时却发现了这样的问题：
贴一下完整错误日志：
Cannot find a version of 'com.android.support:support-annotations' that satisfies the version constraints:
Dependency path 'NewPutMeal:serialportlibrary:unspecified' --> 'com.android.support.test:runner:1.0.2' --> 'com.android.support:support-annotations:27.1.1'
Dependency path 'NewPutMeal:serialportlibrary:unspecified' --> 'com.android.support:appcompat-v7:27.1.0' --> 'com.android.support:support-annotations:27.1.0'
Dependency path 'NewPutMeal:serialportlibrary:unspecified' --> 'com.android.support.test:runner:1.0.2' --> 'com.android.support.test:monitor:1.0.2' --> 'com.android.support:support-annotations:27.1.1'
Dependency path 'NewPutMeal:serialportlibrary:unspecified' --> 'com.android.support.test.espresso:espresso-core:3.0.2' --> 'com.android.support.test:runner:1.0.2' --> 'com.android.support:support-annotations:27.1.1'
Dependency path 'NewPutMeal:serialportlibrary:unspecified' --> 'com.android.support:appcompat-v7:27.1.0' --> 'com.android.support:support-core-utils:27.1.0' --> 'com.android.support:support-annotations:27.1.0'
Dependency path 'NewPutMeal:serialportlibrary:unspecified' --> 'com.android.support:appcompat-v7:27.1.0' --> 'com.android.support:support-fragment:27.1.0' --> 'com.android.support:support-annotations:27.1.0'
Dependency path 'NewPutMeal:serialportlibrary:unspecified' --> 'com.android.support:appcompat-v7:27.1.0' --> 'com.android.support:support-vector-drawable:27.1.0' --> 'com.android.support:support-annotations:27.1.0'
Constraint path 'NewPutMeal:serialportlibrary:unspecified' --> 'com.android.support:support-annotations' strictly '27.1.0' because of the following reason: debugRuntimeClasspath uses version 27.1.0
这个问题之前可没有遇到过啊，从网上翻阅答案，但是并没有解决我的问题。而且看错误日志有点像依赖冲突的日志。嗯是的没有错就是依赖冲突啦，而且可以正常编译运行的依赖冲突。既然是依赖冲突那么就解决冲突就好了。从日子上看就是信息里标红字体的冲突了，当然有的会有更多的版本冲突。解决方案都是一样的：一个一个排除就好啦。这里选择27.1.0为目标版本，27.1.0是需要调整的版本，看“com.android.support.test:runner:1.0.2”是这个依赖，在依赖引用文件找到，修改，更新，同步就可以正常打包了。
