错误：com.android.builder.dexing.DexArchiveMergerException: Unable to merge dex

解决办法：我依赖的包的版本是26.0.0-alpha1，那么无论是app还是引入的module都统一使用26.0.0-alpha1；在app的build.gradle加上一段代码即可：

configurations.all {

    resolutionStrategy.eachDependency { DependencyResolveDetails details ->
        def requested = details.requested
        if (requested.group == 'com.android.support') {
            if (!requested.name.startsWith("multidex")) {
                details.useVersion '26.0.0-alpha1'
            }
        }
    }
}