Error: Cannot find symbol class OkHttpClient

Hello Everyone,

I'm working on creating my weather app. I'm having issues with the build gradle(Module: app) For some reason I think it may not be syncing.

*******This is what's synced for the build gradle(Module:app)*******

apply plugin: 'com.android.application' android { compileSdkVersion 21 buildToolsVersion "21.1.2"

defaultConfig {
    applicationId "com.gbsjr.stromy"
    minSdkVersion 16
    targetSdkVersion 21
    versionCode 1
    versionName "1.0"
}
buildTypes {
    release {
        minifyEnabled false
        proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
    }
}

}

dependencies { compile fileTree(dir: 'libs', include: ['*.jar']) compile 'com.android.support:appcompat-v7:21.0.3' compile 'com.squareup.okhttp:okhttp:2.6.0' }

*******This is my code in the MainActivity Java*******

package com.gbsjr.stromy; import android.app.DownloadManager; import android.os.Bundle; import android.support.v7.app.ActionBarActivity;

public class MainActivity extends ActionBarActivity {

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);



    String apiKey = "2f2875ae75e8063b0bb0ce8de7295a07";
    double latitude = 37.8267;
    double longitude = -122.423;
    String forcastUrl =  "https://api.forecast.io/forecast/" + apiKey + "/"
           + latitude + longitude;


    OkHttpClient client = new OkHttpClient();
    //Request request = new Request.Builder().url(forecastUrl).build();

   // Call call = client.newCall(request);
    //Response response = call.execute();

}

}

Here is my error message. Error:(27, 9) error: cannot find symbol class OkHttpClient

Is there anything I can do resolve this issue? I've already tried the Invalidated/Cache Restart... and even resync the gradle, however this error message persist. Any help would be much appreciated?