Error

FAILURE: Build failed with an exception. * What went wrong: A problem occurred configuring project ‘:file_picker’. > Could not resolve all files for configuration ‘:file_picker:classpath’. > Could not download kotlin-reflect-1.3.11.jar (org.jetbrains.kotlin:kotlin-reflect:1.3.11) > Could not get resource ‘https://repo.maven.apache.org/maven2/org/jetbrains/kotlin/kotlin-reflect/1.3.11/kotlin-reflect-1.3.11.jar’;. > Could not GET ‘https://repo.maven.apache.org/maven2/org/jetbrains/kotlin/kotlin-reflect/1.3.11/kotlin-reflect-1.3.11.jar’;. > No such host is known (repo.maven.apache.org) > Failed to notify project evaluation listener. > Could not get unknown property ‘android’ for project ‘:file_picker’ of type org.gradle.api.Project. > Could not find method implementation() for arguments [project ‘:flutter_plugin_android_lifecycle’] on object of type org.gradle.api.internal.artifacts.dsl.dependencies.DefaultDependencyHandler. > Could not get unknown property ‘android’ for project ‘:file_picker’ of type org.gradle.api.Project. * Try: > Run with –stacktrace option to get the stack trace. > Run with –info or –debug option to get more log output. > Run with –scan to get full insights. * Get more help at https://help.gradle.org BUILD FAILED in 11m 15s [!] Gradle threw an error while downloading artifacts from the network.

Solution

It's a network issue. Check your github proxy setting.