You can open this sample inside a Android Studio IDE using the project importer.

This sample shows how a simple Android application written in Java can be built with Gradle. The application was created following the Build your first app guide.

app/build.gradle
plugins {
    id('com.android.application') version '4.1.1'
}

repositories {
    google()
    jcenter()
}

android {
    compileSdkVersion 30
    buildToolsVersion '30.0.1'
    defaultConfig {
        applicationId 'org.gradle.samples'
        minSdkVersion 16
        targetSdkVersion 30
        versionCode 1
        versionName '1.0'
        testInstrumentationRunner 'androidx.test.runner.AndroidJUnitRunner'
    }
    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro'
        }
    }
}

dependencies {
    implementation 'androidx.appcompat:appcompat:1.1.0'
    implementation 'com.google.android.material:material:1.1.0'
    implementation 'androidx.constraintlayout:constraintlayout:1.1.3'
    implementation 'androidx.navigation:navigation-fragment-ktx:2.2.2'
    implementation 'androidx.navigation:navigation-ui-ktx:2.2.2'
    testImplementation 'junit:junit:4.13'
    androidTestImplementation 'androidx.test.ext:junit:1.1.1'
    androidTestImplementation 'androidx.test.espresso:espresso-core:3.2.0'
}
app/build.gradle.kts
plugins {
    id("com.android.application") version "4.1.1"
}

repositories {
    google()
    jcenter()
}

android {
    compileSdkVersion(30)
    buildToolsVersion("30.0.1")
    defaultConfig {
        applicationId = "org.gradle.samples"
        minSdkVersion(16)
        targetSdkVersion(30)
        versionCode = 1
        versionName = "1.0"
        testInstrumentationRunner = "androidx.test.runner.AndroidJUnitRunner"
    }
    buildTypes {
        getByName("release") {
            isMinifyEnabled = false
            proguardFiles(getDefaultProguardFile("proguard-android-optimize.txt"), "proguard-rules.pro")
        }
    }
}

dependencies {
    implementation("androidx.appcompat:appcompat:1.1.0")
    implementation("com.google.android.material:material:1.1.0")
    implementation("androidx.constraintlayout:constraintlayout:1.1.3")
    implementation("androidx.navigation:navigation-fragment-ktx:2.2.2")
    implementation("androidx.navigation:navigation-ui-ktx:2.2.2")
    testImplementation("junit:junit:4.13")
    androidTestImplementation("androidx.test.ext:junit:1.1.1")
    androidTestImplementation("androidx.test.espresso:espresso-core:3.2.0")
}

To build the application:

$ ./gradlew build