Cannot invoke method allprojects() on null object. A problem occurred evaluating root project 'android'

Question

I am getting the following error while running my flutter app

• What went wrong:

A problem occurred evaluating root project 'android'.

Cannot invoke method allprojects() on null object

• 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 0s

Cannot invoke method allprojects() on null object

Open File 20:26:40: Task execution finished.

The app build.gradle file

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'
}

apply plugin: 'com.android.application'
apply plugin: 'kotlin-android'
apply from: "$flutterRoot/packages/flutter_tools/gradle/flutter.gradle"

android {
    compileSdkVersion 29

    sourceSets {
        main.java.srcDirs += 'src/main/kotlin'
    }

    lintOptions {
        disable 'InvalidPackage'
    }

    defaultConfig {
        // TODO: Specify your own unique Application ID (https://developer.android.com/studio/build/application-id.html).
        applicationId "com.emart.emart_app"
        minSdkVersion 21
        targetSdkVersion 29
        versionCode flutterVersionCode.toInteger()
        versionName flutterVersionName
        testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
        multiDexEnabled true
    }

    buildTypes {
        release {
            // TODO: Add your own signing config for the release build.
            // Signing with the debug keys for now, so `flutter run --release` works.
            signingConfig signingConfigs.debug
        }
    }
}

flutter {
    source '../..'
}

dependencies {
    implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk7:$kotlin_version"
    testImplementation 'junit:junit:4.12'
    androidTestImplementation 'com.android.support.test:runner:1.0.2'
    androidTestImplementation 'com.android.support.test.espresso:espresso-core:3.0.2'
    implementation "com.android.support-v4:27.1.1"
    implementation 'com.google.firebase:firebase-core:17.2.1'
    implementation 'com.google.firebase:firebase-analytics:17.2.1'
}

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

build.gradle

buildscript {
    ext.kotlin_version = '1.3.50'
    repositories {
        jcenter()
        google()
    }

    dependencies {
        classpath 'com.google.gms:google-services:4.3.2'
        classpath 'com.android.tools.build:gradle:3.5.2'
        classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
    }
}.

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

rootProject.buildDir = '../build'
subprojects {
    project.buildDir = "${rootProject.buildDir}/${project.name}"
}
subprojects {
    project.evaluationDependsOn(':app')
}

task clean(type: Delete) {
    delete rootProject.buildDir
}

I have updated all dependencies. Used command Flutter upgrade and then used flutter doctor and it shows no issues. But when I run the app I get the above error in the terminal. Thanks for the help.

Answer 1

As previously pointed out, there's an unexpected character on the project's build.gradle file. Removing this should hopefully fix the issue. Another option that you can try to resolve build issues on Android is by regenerating platform-specific project files. To do so, you can delete the android folder, and regenerate the project files again by running flutter create --platforms=android on the terminal.