Failure on Android 14 (sdk 34):

[10MoSi01]

This stack-overflow page seems to be the solutions to the problem:
https://stackoverflow.com/questions/77520968/why-am-i-encountering-the-error-starting-fgs-without-a-type-when-executing-the

[B-O-B-G-I-T]

You have this error ?
FAILURE: Build failed with an exception.

• What went wrong:
  A problem occurred configuring project ':flutter_nearby_connections'.

Could not create an instance of type com.android.build.api.variant.impl.LibraryVariantBuilderImpl.
Namespace not specified. Specify a namespace in the module's build file. See https://d.android.com/r/tools/upgrade-assistant/set-namespace for information about setting the namespace.

 If you've specified the package attribute in the source AndroidManifest.xml, you can use the AGP Upgrade Assistant to migrate to the namespace value in the build file. Refer to https://d.android.com/r/tools/upgrade-assistant/agp-upgrade-assistant for general information about using the AGP Upgrade Assistant.

[joshuamoreno1]

I have the same error

[kamaravichow]

Follow this to solve the issue => https://stackoverflow.com/a/78744535/10530434

[B-O-B-G-I-T]

I made the fix with the namespace, but new problem here is the gradle:

group 'com.nankai.flutter_nearby_connections'
version '1.0-SNAPSHOT'

buildscript {
    ext.kotlin_version = '1.7.10'
    repositories {
        google()
        jcenter()
    }

    dependencies {
        classpath 'com.android.tools.build:gradle:3.5.0'
        classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
    }
}

rootProject.allprojects {
    repositories {
        google()
        jcenter()
    }
}

apply plugin: 'com.android.library'
apply plugin: 'kotlin-android'

android {
    namespace 'com.nankai.flutter_nearby_connections'
    compileSdkVersion 34

    sourceSets {
        main.java.srcDirs += 'src/main/kotlin'
    }
    defaultConfig {
        minSdkVersion 16
        targetSdkVersion 34
    }
    lintOptions {
        disable 'InvalidPackage'
    }
}

dependencies {
    api 'com.google.android.gms:play-services-nearby:18.5.0'
    implementation 'com.google.code.gson:gson:2.10.1'
    implementation 'com.google.android.gms:play-services-location:17.1.0'
    implementation 'androidx.core:core-ktx:1.9.0'
    implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk7:$kotlin_version"
}
repositories {
    mavenCentral()
}

I have this error
Note: Some input files use or override a deprecated API.
Note: Recompile with -Xlint:deprecation for details.

FAILURE: Build failed with an exception.

• What went wrong:
  Execution failed for task ':flutter_nearby_connections:compileReleaseKotlin'.

Inconsistent JVM-target compatibility detected for tasks 'compileReleaseJavaWithJavac' (1.8) and 'compileReleaseKotlin' (17).

Consider using JVM Toolchain: https://kotl.in/gradle/jvm/toolchain
Learn more about JVM-target validation: https://kotl.in/gradle/jvm/target-validation

if anyone knows

[B-O-B-G-I-T]

Thanks to @kamaravichow and pull requests #62 and #63, I was able to fix the problem. Maybe this will solve yours too.