Flutter升级Firebase依赖后Gradle插件废弃问题求助

升级Flutter（3.19.0稳定版）及Firebase依赖后，构建Android应用时出现两类核心警告：Gradle插件命令式应用方式废弃、NDK版本不足，尝试flutter clean和flutter build无效。以下是针对性解决方案：

一、修复Gradle插件命令式应用废弃警告 #

该警告源于当前使用了废弃的apply from方式引入插件，需迁移至声明式plugins块。

1. 修改settings.gradle #

替换原有插件引入代码，修改后完整内容：

include ':app'

def localPropertiesFile = new File(rootProject.projectDir, "local.properties")
def properties = new Properties()

assert localPropertiesFile.exists()
localPropertiesFile.withReader("UTF-8") { reader -> properties.load(reader) }

def flutterSdkPath = properties.getProperty("flutter.sdk")
assert flutterSdkPath != null, "flutter.sdk not set in local.properties"

plugins {
    id "dev.flutter.flutter-plugin-loader" version "1.0.0" apply false
}

2. 修改app/build.gradle #

将开头的apply plugin和apply from语句替换为plugins块，修改后开头部分如下：

def localProperties = new Properties()
def localPropertiesFile = rootProject.file('local.properties')
if (localPropertiesFile.exists()) {
    localPropertiesFile.withReader('UTF-8') { reader ->
        localProperties.load(reader)
    }
}

def flutterRoot = localProperties.getProperty('flutter.sdk')
if (flutterRoot == null) {
    throw new FileNotFoundException("Flutter SDK not found. Define location with flutter.sdk in the local.properties file.")
}

def flutterVersionCode = localProperties.getProperty('flutter.versionCode')
if (flutterVersionCode == null) {
    flutterVersionCode = '1'
}

def flutterVersionName = localProperties.getProperty('flutter.versionName')
if (flutterVersionName == null) {
    flutterVersionName = '1.0'
}

plugins {
    id "com.android.application"
    id "kotlin-android"
    id "dev.flutter.flutter-gradle-plugin"
    id "com.google.gms.google-services" // 将原来末尾的apply plugin移到此处
}

def keystoreProperties = new Properties()
def keystorePropertiesFile = rootProject.file('key.properties')
if (keystorePropertiesFile.exists()) {
    keystoreProperties.load(new FileInputStream(keystorePropertiesFile))
 }

文件其余部分（android块、flutter块、dependencies等）保持不变。

二、修复NDK版本不足警告 #

直接在app/build.gradle的android块中指定要求的NDK版本：
找到android块中的ndkVersion flutter.ndkVersion，替换为：

ndkVersion "25.1.8937393"

修改后的android块开头示例：

android {
    namespace "com.example.egyreef_smart_doser"
    compileSdkVersion flutter.compileSdkVersion
    ndkVersion "25.1.8937393"

    // 其余原有代码不变
}

三、关于deprecated API和unchecked操作的提示 #

日志中提到的cloud_firestore插件内部代码警告，属于插件自身兼容性问题，不影响当前应用构建，等待插件官方更新即可。若需查看详细警告信息，可在编译时添加-Xlint:deprecation或-Xlint:unchecked参数，但一般无需额外处理。

内容的提问来源于stack exchange，提问作者Mohamed Gendia