all com.android.libraries support must use same version when including play service in gradle

Question

I just included ads into my app and as part of that process I included

/*google play plugin for adMob*/
    compile 'com.google.android.gms:play-services:10.2.1'

as a dependency in my gradle app file. But I'm getting a red underscore error under

compile 'com.android.support:appcompat-v7:26.+'

error says: all com.android.libraries support must use same version specification. mixing can lead to crashes.

apply plugin: 'com.android.application'

android {
    compileSdkVersion 26
    buildToolsVersion "26.0.2"
    defaultConfig {
        applicationId "org.pctechtips.george.dailyquotes"
        minSdkVersion 16
        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 {
    compile fileTree(dir: 'libs', include: ['*.jar'])
    androidTestCompile('com.android.support.test.espresso:espresso-core:2.2.2', {
        exclude group: 'com.android.support', module: 'support-annotations'
        /*firebase */
//        compile 'com.google.firebase:firebase-core:10.2.1'
    })
    //    compile 'com.android.support:appcompat-v7:21.0.3'
    compile 'com.android.support:appcompat-v7:26.+'
    compile 'com.android.support.constraint:constraint-layout:1.0.2'
    compile 'com.android.support:support-v4:26.+'
    testCompile 'junit:junit:4.12'
    /*google play plugin for adMob*/
    compile 'com.google.android.gms:play-services:10.2.1'
}

Something in that older version of google play services probably uses something from the support library — tyczj, Jun 25 '18 at 20:48
https://github.com/googlesamples/android-architecture-components/issues/140 — Adi Mabfalin, Jun 26 '18 at 06:08

score 0 · Answer 1 · answered Jun 26 '18 at 13:37

play-services-ads:10.2.1 has a dependency onto play-services-basement:10.2.1 which has a dependency onto com.android.support:support-v4:24.0.0. This is likely the source of the mismatch.

See All com.android.support libraries must use the exact same version specification for more context.

all com.android.libraries support must use same version when including play service in gradle

1 Answers1