一般签名都是放在buildTypes里面：

...
android {...defaultConfig {...}signingConfigs {release {storeFile file("myreleasekey.keystore")storePassword "password"keyAlias "MyReleaseKey"keyPassword "password"}}buildTypes {release {...signingConfig signingConfigs.release}}
}

但是多渠道时，使用配置的优先级从高到低分别是buildTypes、productFlavor、defaultConfig，如果按上面配置的话，根本修改不了签名。所以修改成以下：

android {...signingConfigs {release {storeFile file("myreleasekey.keystore")storePassword "password"keyAlias "MyReleaseKey"keyPassword "password"}demo {storeFile file("myreleasekey.keystore")storePassword "password"keyAlias "MyReleaseKey"keyPassword "password"}}defaultConfig {signingConfig signingConfigs.release //默认签名}buildTypes {debug{signingConfig null //这里一定要置null，否则gralde会插入默认签名}release{...}}// Specifies one flavor dimension.flavorDimensions "version"productFlavors {demo {dimension "version"applicationIdSuffix ".demo"versionNameSuffix "-demo"signingConfig signingConfigs.demo //渠道签名}full {dimension "version"applicationIdSuffix ".full"versionNameSuffix "-full"}}
}

按上面配置完后，渠道可以按照自己需求替换签名了。特别注意debug类型那里要置signingConfig null，否则编译debug版本时签名会不生效，因为gradle会插入默认签名，替换掉渠道的签名。