Execution failed for task ':app:transformClassesAndResourcesWithProguardForRelease'.

1.Execution failed for task ':app:transformClassesAndResourcesWithProguardForRelease'.

原因解析：

gradle 从 2.14.1 升级至 3.5.1

react-native 混淆压缩处理失败

2.解决方案

在 android/app/proguard-rules.pro 中添加 

-ignorewarnings -keep class * { public private *; }