Error:(1, 0) Plugin with id 'kotlin-android-extensions' not found

Question

apply plugin: 'kotlin-android-extensions'.

When i add this extensions in android studio preview, give me this error "Error:(1, 0) Plugin with id 'kotlin-android-extensions' not found.".

My build gradle

   apply plugin: 'com.android.application'

android {
    compileSdkVersion 26
    buildToolsVersion "26.0.1"
    defaultConfig {
        applicationId "com.example.mohamed_elbaz.myapplication"
        minSdkVersion 15
        targetSdkVersion 26
        versionCode 1
        versionName "1.0"
        testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
    }
    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
        }
    }
}

dependencies {
    implementation fileTree(dir: 'libs', include: ['*.jar'])
    implementation 'com.android.support:appcompat-v7:26.0.2'
    implementation 'com.android.support.constraint:constraint-layout:1.0.2'
    testImplementation 'junit:junit:4.12'
    androidTestImplementation 'com.android.support.test:runner:1.0.1'
    androidTestImplementation 'com.android.support.test.espresso:espresso-core:3.0.1'
}

Answer 1

The build.gradle snippet you posted looks like the config inside your app module. What does the build.gradle in your project's root directory look like? To add the kotlin plugin dependencies it should look something like this:

buildscript {
    ext.kotlin_version = '1.1.50'
    repositories {
        jcenter()
        google()

    }
    dependencies {
        classpath 'com.android.tools.build:gradle:3.0.0-beta6'
        classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"

        // NOTE: Do not place your application dependencies here; they belong
        // in the individual module build.gradle files
    }
}

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

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

The important part being the line classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"which adds the kotlin plugins.

Answer 2

To use the plugin, you have to add it in your root build.gradle file

buildscript {
ext.kotlin_version = '1.1.60'
    repositories {
        jcenter()
        maven {
            url 'https://maven.google.com'
        }
    }

    dependencies {
        classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
    }
}