• • bounty明天到期**。回答此问题可获得+100声望奖励。Alexander Dyagilev希望吸引更多人关注此问题。

我希望使用Firebase的方式与任何不使用Qt的原生Android应用程序相同（即使用Java）。我已经有一个（一切正常）。
现在，我尝试将Firebase添加到我现有的Qt项目中。现在，我尝试将所有必需的依赖项添加到build.gradle中（这样我就可以在我的Qt项目的Java源代码部分中使用Firebase APIs），但遇到了奇怪的错误。
我不擅长Gradle，所以任何帮助都是感激的（如果这是可能的，因为我使用的是相当旧的Qt 5.12.12）。
这是我拥有的build.gradle（构建和运行良好）：

buildscript {
    repositories {
        google()
        jcenter()
    }

    dependencies {
        classpath 'com.android.tools.build:gradle:3.2.0'
    }
}

repositories {
    google()
    jcenter()
}

apply plugin: 'com.android.application'

dependencies {
    implementation fileTree(dir: 'libs', include: ['*.jar', '*.aar'])
    implementation 'androidx.appcompat:appcompat:1.0.2'
    implementation 'androidx.constraintlayout:constraintlayout:1.1.3'
    implementation 'androidx.swiperefreshlayout:swiperefreshlayout:1.1.0'
    implementation 'com.google.code.gson:gson:2.7'
    implementation 'com.jakewharton:process-phoenix:2.1.2' // https://github.com/JakeWharton/ProcessPhoenix
    implementation 'me.dm7.barcodescanner:zxing:1.9.13' // https://github.com/dm77/barcodescanner
}

android {
    /*******************************************************
     * The following variables:
     * - androidBuildToolsVersion,
     * - androidCompileSdkVersion
     * - qt5AndroidDir - holds the path to qt android files
     *                   needed to build any Qt application
     *                   on Android.
     *
     * are defined in gradle.properties file. This file is
     * updated by QtCreator and androiddeployqt tools.
     * Changing them manually might break the compilation!
     *******************************************************/

    // Buggy thing: fails to build. Needs to be replaced with actual numbers.
    // https://stackoverflow.com/a/46290586/3765267
    /*compileSdkVersion androidCompileSdkVersion.toInteger()
    buildToolsVersion androidBuildToolsVersion*/
    compileSdkVersion 30
    buildToolsVersion "30.0.2"

    sourceSets {
        main {
            manifest.srcFile 'AndroidManifest.xml'
            java.srcDirs = [qt5AndroidDir + '/src', 'src', 'java']
            aidl.srcDirs = [qt5AndroidDir + '/src', 'src', 'aidl']
            res.srcDirs = [qt5AndroidDir + '/res', 'res']
            resources.srcDirs = ['src']
            renderscript.srcDirs = ['src']
            assets.srcDirs = ['assets']
            jniLibs.srcDirs = ['libs']
       }
    }

    lintOptions {
        abortOnError false
    }
}

这是build.gradle，包含我尝试添加的所有依赖项（我已经将classpath 'com.google.gms:google-services:4.3.14'添加到dependencies节和apply plugin: 'com.google.gms.google-services'行）：

buildscript {
    repositories {
        google()
        jcenter()
    }

    dependencies {
        classpath 'com.android.tools.build:gradle:3.2.0'
        classpath 'com.google.gms:google-services:4.3.14'
    }
}

repositories {
    google()
    jcenter()
}

apply plugin: 'com.android.application'
apply plugin: 'com.google.gms.google-services'

dependencies {
    implementation fileTree(dir: 'libs', include: ['*.jar', '*.aar'])
    implementation 'androidx.appcompat:appcompat:1.0.2'
    implementation 'androidx.constraintlayout:constraintlayout:1.1.3'
    implementation 'androidx.swiperefreshlayout:swiperefreshlayout:1.1.0'
    implementation 'com.google.code.gson:gson:2.7'
    implementation 'com.jakewharton:process-phoenix:2.1.2' // https://github.com/JakeWharton/ProcessPhoenix
    implementation 'me.dm7.barcodescanner:zxing:1.9.13' // https://github.com/dm77/barcodescanner
}

android {
    /*******************************************************
     * The following variables:
     * - androidBuildToolsVersion,
     * - androidCompileSdkVersion
     * - qt5AndroidDir - holds the path to qt android files
     *                   needed to build any Qt application
     *                   on Android.
     *
     * are defined in gradle.properties file. This file is
     * updated by QtCreator and androiddeployqt tools.
     * Changing them manually might break the compilation!
     *******************************************************/

    // Buggy thing: fails to build. Needs to be replaced with actual numbers.
    // https://stackoverflow.com/a/46290586/3765267
    /*compileSdkVersion androidCompileSdkVersion.toInteger()
    buildToolsVersion androidBuildToolsVersion*/
    compileSdkVersion 30
    buildToolsVersion "30.0.2"

    sourceSets {
        main {
            manifest.srcFile 'AndroidManifest.xml'
            java.srcDirs = [qt5AndroidDir + '/src', 'src', 'java']
            aidl.srcDirs = [qt5AndroidDir + '/src', 'src', 'aidl']
            res.srcDirs = [qt5AndroidDir + '/res', 'res']
            resources.srcDirs = ['src']
            renderscript.srcDirs = ['src']
            assets.srcDirs = ['assets']
            jniLibs.srcDirs = ['libs']
       }
    }

    lintOptions {
        abortOnError false
    }
}

现在，我在尝试构建项目时遇到了以下奇怪的错误：

Generating Android Package
  Input file: C:/Work/Source/build-fdm-Android_Qt_5_12_12_Clang_armeabi_v7a-Debug/ui/android-libfdm.so-deployment-settings.json
  Output directory: C:/Work/Source/build-fdm-Android_Qt_5_12_12_Clang_armeabi_v7a-Debug/ui/android-build/
  Application binary: C:/Work/Source/build-fdm-Android_Qt_5_12_12_Clang_armeabi_v7a-Debug/bin/libfdm.so
  Android build platform: android-33
  Install to device: No

FAILURE: Build failed with an exception.

* Where:
Build file 'C:\Work\Source\build-fdm-Android_Qt_5_12_12_Clang_armeabi_v7a-Debug\ui\android-build\build.gradle' line: 18

* What went wrong:
A problem occurred evaluating root project 'android-build'.
> ASCII

* 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 3s

• • 第一项补充。**我可以使用Qt 6.4.1 + Firebase进行构建。问题是关于Qt 5.12.12。我怀疑原因是它使用的Gradle版本太旧（4.6）或类似的东西。