Breakupsong adlı üyeden alıntı: mesajı görüntüle
Sdk ile alakasi olmayabilir.Build.gradle dosyanizda repositories içine mavenCentral() ekleyin.Sync dedikten sonra build -> clean project deyin.

Mavencentral ekliyse build.gradle kodunuzu da paylaşın.

repositories { maven { url 'https://plugins.gradle.org/m2/' }}

Yukarıdaki gibi eklenmiş hocam. Full grandle dosyası aşağıdaki gibidir hala çözemedim sorunu

buildscript {    repositories {        maven { url 'https://plugins.gradle.org/m2/' }    }    dependencies {        classpath 'gradle.plugin.com.onesignal:onesignal-gradle-plugin:0.12.6'    }}apply plugin: 'com.onesignal.androidsdk.onesignal-gradle-plugin'repositories {    maven { url 'https://maven.google.com' }}apply plugin: 'com.android.application'android {    compileSdkVersion 29    defaultConfig {        applicationId "coxxx"        minSdkVersion 16        targetSdkVersion 29        versionCode 1        versionName "1.0"        multiDexEnabled true        testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"        buildConfigField "String", "BASE_HOST", ""https://d2isj403unfbyl.cloudfront.net""        buildConfigField "String", "BASE_CARRIER_ID", ""xxxx""        buildConfigField "String", "BASE_OAUTH_METHOD", ""anonymous""        buildConfigField "String", "SHARED_PREFS", ""NORTHGHOST_SHAREDPREFS""        buildConfigField "String", "STORED_HOST_URL_KEY", ""com.northghost.afvclient.STORED_HOST_KEY""        buildConfigField "String", "STORED_CARRIER_ID_KEY", ""com.northghost.afvclient.CARRIER_ID_KEY""        //one Signal        manifestPlaceholders = [                onesignal_app_id: 'xx7',                // Project number pulled from dashboard, local value is ignored.                onesignal_google_project_number: 'REMOTE'        ]    }    signingConfigs {        release {        }    }    buildTypes {        release {            minifyEnabled true            signingConfig signingConfigs.release            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'        }    }    compileOptions {        sourceCompatibility 1.8        targetCompatibility 1.8    }}dependencies {    implementation fileTree(dir: 'libs', include: ['*.jar'])    implementation 'com.github.AnchorFreePartner.hydra-sdk-android:sdk:3.3.1'    implementation 'com.github.AnchorFreePartner.hydra-sdk-android:openvpn:3.3.1'    implementation 'androidx.appcompat:appcompat:1.2.0'    implementation 'androidx.cardview:cardview:1.0.0'    implementation 'androidx.recyclerview:recyclerview:1.1.0'    implementation 'com.google.android.material:material:1.3.0-alpha02'    implementation 'com.jakewharton:butterknife:10.2.3'    implementation 'androidx.constraintlayout:constraintlayout:2.0.0'    implementation 'androidx.legacy:legacy-support-v4:1.0.0'    annotationProcessor 'com.jakewharton:butterknife-compiler:10.2.3'    implementation 'androidx.multidex:multidex:2.0.1'    //cutoms things    implementation 'com.airbnb.android:lottie:3.4.1'    //one Signal    implementation 'com.onesignal:OneSignal:3.15.2'    //ad-mob    implementation 'com.google.android.gms:play-services-ads:19.3.0'    //customs    implementation 'com.github.pepperonas:materialdialog:0.3.4'    //Preference Library    implementation 'com.pixplicity.easyprefs:library:1.9.0'    //speedTest    implementation 'fr.bmartel:jspeedtest:1.32.1'    //facebook ads    implementation 'com.facebook.android:audience-network-sdk:5.8.0'    //Drawer Library    implementation 'com.infideap.drawerbehavior:drawer-behavior:1.0.1'    //rating things    implementation 'com.codemybrainsout.rating:ratingdialog:1.0.8'    implementation 'com.github.CaiJingLong:Android-CustomRatingBar:-SNAPSHOT'    //Android Ripple background animation.    implementation 'com.skyfishjy.ripplebackground:library:1.0.1'    implementation 'com.balysv:material-ripple:1.0.2'                  // ripple effect    //Imageshadow Library    //checkBox    implementation 'net.igenius:customcheckbox:1.3'    //Google play billing    def billing_version = "3.0.0"    implementation "com.android.billingclient:billing:$billing_version"    implementation 'com.facebook.android:audience-network-sdk:5.9.1'    //Custom Toast    implementation 'com.github.GrenderG:Toasty:1.4.2'}