1.在build.gradle文件中 添加以下代码再sync 以下就可以了
apply plugin: 'me.tatarka.retrolambda'
buildscript {
repositories {
mavenCentral()
}
dependencies {
classpath 'me.tatarka:gradle-retrolambda:3.2.5'
}
}
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compileOptions{
sourceCompatibility 1.8
targetCompatibility 1.8
}
}