简单的android项目不适用于离子库

Question

我知道该怎么做。最后我创建了简单的android项目并附加了Ion库，制作了ImageView等等。但即使是简单的项目也有致命的错误。我做错了什么？

activity_main.xml中：

    <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent"
    android:layout_height="match_parent" android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    android:paddingBottom="@dimen/activity_vertical_margin" tools:context=".MainActivity">

    <TextView android:text="@string/hello_world" android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:id="@+id/textView" />

    <ImageView
        android:layout_width="300dp"
        android:layout_height="300dp"
        android:id="@+id/imageView"
        android:layout_centerVertical="true"
        android:layout_centerHorizontal="true" />

</RelativeLayout>

MainActivity.java：

    package ru.true_code.android.ionexample;

import android.app.Activity;
import android.support.v7.app.ActionBarActivity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.ImageView;

import com.koushikdutta.ion.Ion;


public class MainActivity extends Activity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        ImageView iv = (ImageView) findViewById(R.id.imageView);

        Ion.with(iv).placeholder(R.drawable.ic_launcher)
                .error(R.drawable.ic_launcher)
                .load("http://square.github.io/picasso/static/sample.png");

    }



}

清单文件：

    <?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="ru.true_code.android.ionexample" >
    <uses-permission android:name="android.permission.INTERNET" />

    <application
        android:allowBackup="true"
        android:icon="@drawable/ic_launcher"
        android:label="@string/app_name"
        android:theme="@style/AppTheme" >
        <activity
            android:name=".MainActivity"
            android:label="@string/app_name" >
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
    </application>

</manifest>

致命错误（logcat）：

01-29 20:50:00.800  14648-14648/ru.true_code.android.ionexample E/AndroidRuntime﹕ FATAL EXCEPTION: main
    Process: ru.true_code.android.ionexample, PID: 14648
    java.lang.NoClassDefFoundError: Failed resolution of: Lcom/koushikdutta/async/util/HashList;
            at com.koushikdutta.ion.Ion.<init>(Ion.java:145)
            at com.koushikdutta.ion.Ion.getInstance(Ion.java:114)
            at com.koushikdutta.ion.Ion.getDefault(Ion.java:100)
            at com.koushikdutta.ion.Ion.with(Ion.java:124)
            at ru.true_code.android.ionexample.MainActivity.onCreate(MainActivity.java:21)
            at android.app.Activity.performCreate(Activity.java:5933)
            at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1105)
            at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2251)
            at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2360)
            at android.app.ActivityThread.access$800(ActivityThread.java:144)
            at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1278)
            at android.os.Handler.dispatchMessage(Handler.java:102)
            at android.os.Looper.loop(Looper.java:135)
            at android.app.ActivityThread.main(ActivityThread.java:5221)
            at java.lang.reflect.Method.invoke(Native Method)
            at java.lang.reflect.Method.invoke(Method.java:372)
            at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:899)
            at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:694)
     Caused by: java.lang.ClassNotFoundException: Didn't find class "com.koushikdutta.async.util.HashList" on path: DexPathList[[zip file "/data/app/ru.true_code.android.ionexample-1/base.apk"],nativeLibraryDirectories=[/vendor/lib, /system/lib]]
            at dalvik.system.BaseDexClassLoader.findClass(BaseDexClassLoader.java:56)
            at java.lang.ClassLoader.loadClass(ClassLoader.java:511)
            at java.lang.ClassLoader.loadClass(ClassLoader.java:469)
            at com.koushikdutta.ion.Ion.<init>(Ion.java:145)
            at com.koushikdutta.ion.Ion.getInstance(Ion.java:114)
            at com.koushikdutta.ion.Ion.getDefault(Ion.java:100)
            at com.koushikdutta.ion.Ion.with(Ion.java:124)
            at ru.true_code.android.ionexample.MainActivity.onCreate(MainActivity.java:21)
            at android.app.Activity.performCreate(Activity.java:5933)
            at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1105)
            at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2251)
            at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2360)
            at android.app.ActivityThread.access$800(ActivityThread.java:144)
            at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1278)
            at android.os.Handler.dispatchMessage(Handler.java:102)
            at android.os.Looper.loop(Looper.java:135)
            at android.app.ActivityThread.main(ActivityThread.java:5221)
            at java.lang.reflect.Method.invoke(Native Method)
            at java.lang.reflect.Method.invoke(Method.java:372)
            at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:899)
            at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:694)
    Suppressed: java.lang.ClassNotFoundException: com.koushikdutta.async.util.HashList
            at java.lang.Class.classForName(Native Method)
            at java.lang.BootClassLoader.findClass(ClassLoader.java:781)
            at java.lang.BootClassLoader.loadClass(ClassLoader.java:841)
            at java.lang.ClassLoader.loadClass(ClassLoader.java:504)
            ... 19 more
     Caused by: java.lang.NoClassDefFoundError: Class not found using the boot class loader; no stack available