Error:(28, 13) Failed to resolve: com.squareup.okhttp3:okhttp:3.2.0

Question

I have a problem with android studio.

I have added the .jar file of okhttp from this link : https://github.com/square/okhttp to my libs directory on my android studio. and when I try to add this line : compile 'com.squareup.okhttp3:okhttp:3.2.0' in the dependencies in build.gradle(Module:app), after trying to syncing it I get error 28, 13. Actually after researching I found out that I can't compile anything in dependencies and sync it remember that I have checked my "android SDK build tool" is installed.

hear is the whole of my code in build.gradle(app) directory:

apply plugin: 'com.android.application'

android {
    compileSdkVersion 23
    buildToolsVersion "23.0.1"

 defaultConfig {
        applicationId "com.example.kasra.stormy"
        minSdkVersion 14
        targetSdkVersion 23
        versionCode 1
        versionName "1.0"
    }
    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
        }
    }
}

dependencies {
    compile fileTree(dir: 'libs', include: ['*.jar'], )
    testCompile 'junit:junit:4.12'
    compile 'com.android.support:appcompat-v7:23.1.1'
    compile 'com.android.support:design:23.1.1'
    compile files('libs/okhttp-3.2.0.jar')
    compile 'com.squareup.okhttp3:okhttp:3.2.0'
}

I'll be very glad and thankful if someone help me fix this problem.

Thank you very much:)

Answer 1

Either your internet is bad and you can't download that file from JCenter, or you are just missing a repositories section in your gradle file.

apply plugin: 'com.android.application'

repositories {
    jcenter()
}

Also, if you are going to be compiling using gradle instead of a JAR file, then delete the file libs/okhttp-3.2.0.jar and remove the line that says compile files('libs/okhttp-3.2.0.jar').

It is also worth mentioning that you don't need any lines that start with compile files('libs/ because compile fileTree(dir: 'libs', include: ['*.jar'], ) already includes all JAR files within the libs/ folder.

Answer 2

It may help someone. In my case after update com.squareup.okhttp3 to the latest version, I got this error in Android Java libaray. Then I update the Java version to 1.8 which solved my problem.

targetCompatibility = '1.8'
sourceCompatibility = '1.8'