java.lang.NoClassDefFoundError:org.achartengine.model.CategorySeries AChartLibrary中的错误

我正在尝试使用AChartLibrary创建一个拨号表（我完全迷路了。我不知道怎么做，我正在尝试我的手，但没有用，所以欢迎任何可能有帮助的教程）

我已经设法实现了以下图表

import android.app.Fragment;
import android.graphics.Color;
import android.os.Bundle;
import android.view.ViewGroup;
import android.view.View;
import android.view.LayoutInflater;
import android.widget.GridLayout;
import android.widget.LinearLayout;
import org.achartengine.GraphicalView;
import org.achartengine.model.CategorySeries;
import org.achartengine.ChartFactory;
import org.achartengine.renderer.DefaultRenderer;
import org.achartengine.renderer.DialRenderer;
import org.achartengine.renderer.DialRenderer.Type;
import org.achartengine.renderer.SimpleSeriesRenderer;

public class Fragment_Statistics extends Fragment {
    private GraphicalView mChartView;
    public double MAX=180.00,MIN=0.00;
    public View onCreateView(LayoutInflater layoutInflater,ViewGroup container,Bundle SavedInstances){
        View statistics_fragment=getActivity().getLayoutInflater().inflate(R.layout.fragment_statistics, null);
        /** Colors to be used for the pie slices. */
        int[] COLORS = new int[] { Color.GREEN, Color.BLUE, Color.MAGENTA, Color.CYAN };
        /** The main series that will include all the data. */
        CategorySeries mSeries = new CategorySeries("Dial Chart");
        mSeries.add(MAX);
        /** The main renderer for the main dataset. */
        DialRenderer mRenderer = new DialRenderer();
        mRenderer.setAngleMin(MIN);
        mRenderer.setAngleMax(MAX);
        mRenderer.setMaxValue(MAX);
        mChartView=ChartFactory.getDialChartView(getActivity(),mSeries,mRenderer);
        return statistics_fragment;
    }

无论何时执行它，我都会得到以下错误

 java.lang.NoClassDefFoundError: org.achartengine.model.CategorySeries
            at com.spintum.preexam.Fragment_Statistics.onCreateView(Fragment_Statistics.java:30)
            at android.app.Fragment.performCreateView(Fragment.java:1700)
            at android.app.FragmentManagerImpl.moveToState(FragmentManager.java:890)
            at android.app.FragmentManagerImpl.moveToState(FragmentManager.java:1062)
            at android.app.BackStackRecord.run(BackStackRecord.java:698)
            at android.app.FragmentManagerImpl.execPendingActions(FragmentManager.java:1447)
            at android.app.Activity.performStart(Activity.java:5273)
            at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2311)
            at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2390)
            at android.app.ActivityThread.access$800(ActivityThread.java:151)
            at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1321)
            at android.os.Handler.dispatchMessage(Handler.java:110)
            at android.os.Looper.loop(Looper.java:193)
            at android.app.ActivityThread.main(ActivityThread.java:5292)
            at java.lang.reflect.Method.invokeNative(Native Method)
            at java.lang.reflect.Method.invoke(Method.java:515)
            at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:824)
            at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:640)
            at dalvik.system.NativeStart.main(Native Method)

错误指向

CategorySeries

行，如您所见，我已经导入了必要的文件，但仍然显示错误

这也处理了类似的情况，但解决方案是为eclipse而不是android studio提供的。上述帖子中的答案似乎表明问题出在gradle文件中，但我的文件似乎是正确的

格拉德尔：

apply plugin: 'com.android.application'
apply plugin: 'com.google.gms.google-services'
android {
    compileSdkVersion 22
    buildToolsVersion "23.0.3"

    defaultConfig {
        applicationId "com.spintum.preexam"
        minSdkVersion 19
        targetSdkVersion 22
        versionCode 1
        versionName "1.0"
        multiDexEnabled true
    }
    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
        }
    }
}
repositories {
    mavenCentral()
}
dependencies {
//    compile fileTree (dir:'libs',include:'achartengine-*.jar')
    //compile fileTree('libs/achartengine-1.1.0.jar')
    compile fileTree(include: ['*.jar'], dir: 'libs')
    testCompile 'junit:junit:4.12'
    compile 'com.android.support:percent:22.2.0'
    compile 'com.android.support:appcompat-v7:22.2.1'
    compile 'com.android.support:design:22.2.1'
    compile 'com.android.support:support-v4:22.2.0'
    compile 'com.google.code.gson:gson:2.3.1'
    compile 'com.google.android.gms:play-services:8.3.0'
    compile 'com.google.android.gms:play-services-auth:8.3.0'
    compile 'com.google.android.gms:play-services-identity:8.3.0'
    compile 'com.google.android.gms:play-services-plus:8.3.0'
    compile 'com.google.android.gms:play-services-location:8.3.0'
    compile 'com.android.support:multidex:1.0.0'
    compile 'com.github.markushi:circlebutton:1.1'
    compile 'com.facebook.android:facebook-android-sdk:4.0.0'
    compile 'com.ToxicBakery.viewpager.transforms:view-pager-transforms:1.2.32@aar'
}

导致此错误的原因是什么？如何纠正？感谢您的一切帮助