android: 报错:BuildConfig fields, but the feature is disabled

一，报错信息:

给buildTypes增加了debug段后，

    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro'
            buildConfigField "String", "ENV", '"prod"'
        }
        debug {
            buildConfigField "String", "ENV", '"devel"'
        }
    }

出现报错，如下:

                        Build Type 'debug' contains custom BuildConfig fields, but the feature is disabled.
                        To enable the feature, add the following to your module-level build.gradle:
`android.buildFeatures.buildConfig true`

二，解决:

在build.gradle中，android段增加

    buildFeatures {
        buildConfig true
    }

如下:

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