Robolectric错误：无法访问DownloadManager

Question

我决定为我正在开发的android应用程序编写一些单元测试。 我选择了Robolectric（2.3版）。 我是根据我在这里找到的教程完成的：

@Config(emulateSdk = 18)
@RunWith(RobolectricTestRunner.class)
public class MainTest {

    private Main mainActivity;

    @Before
    public void setup() {
         mainActivity = Robolectric.buildActivity(Main.class).create().get();
    }

    @Test
    public void shouldStartNextActivityWhenOnePlayerButtonWasClicked() throws Exception {
        Button button = (Button) mainActivity.findViewById(R.id.onePlayer);
        button.performClick();
        Intent intent = Robolectric.shadowOf(mainActivity).peekNextStartedActivity();
        assertThat(intent.getComponent().getClassName()).isEqualTo(NextActivity.class.getCanonicalName());
}

在运行测试期间，出现以下错误：

[ERROR] Failed to execute goal org.apache.maven.plugins:maven-compiler-plugin:2.3.2:testCompile (default-testCompile) on project app: Compilation failure
[ERROR] \workspace\app\src\test\java\com\example\app\activity\MainTest.java:[36,35] error: cannot access DownloadManager

它指示以下行（shadowOf方法）存在问题：

Intent intent = Robolectric.shadowOf(mainActivity).peekNextStartedActivity();

有人可以解释为什么会出现错误以及如何解决吗？ 也许Robolectric不是我做出的最佳选择？

编辑：我想这个问题可能在我的pom.xml中。 我使用的是robolectric（具有较小的大小），而不是教程中指示的robolectric-with-dependencies：

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
  <modelVersion>4.0.0</modelVersion>
  <groupId>com.example.app</groupId>
  <artifactId>app</artifactId>
  <version>1.0-SNAPSHOT</version>
  <packaging>apk</packaging>
  <name>app</name>

    <repositories>
        <repository>
            <id>android-support</id>
            <url>file://${env.ANDROID_HOME}/extras/android/m2repository</url>
        </repository>
    </repositories>

  <dependencies>
      <dependency>
          <groupId>com.google.android</groupId>
          <artifactId>android</artifactId>
          <version>2.2.1</version>
          <scope>provided</scope>
      </dependency>

      <dependency>
          <groupId>org.robolectric</groupId>
          <artifactId>robolectric</artifactId>
          <version>2.3</version>
          <scope>test</scope>
      </dependency>

      <dependency>
          <groupId>junit</groupId>
          <artifactId>junit</artifactId>
          <version>4.8.2</version>
          <scope>test</scope>
      </dependency>
  </dependencies>

  <build>
    <plugins>
      <plugin>
        <groupId>com.jayway.maven.plugins.android.generation2</groupId>
        <artifactId>maven-android-plugin</artifactId>
        <version>2.8.0</version>
        <configuration>
          <androidManifestFile>${project.basedir}/AndroidManifest.xml</androidManifestFile>
          <assetsDirectory>${project.basedir}/assets</assetsDirectory>
          <resourceDirectory>${project.basedir}/res</resourceDirectory>
          <nativeLibrariesDirectory>${project.basedir}/src/main/native</nativeLibrariesDirectory>
          <sdk>
            <platform>10</platform>
          </sdk>
          <deleteConflictingFiles>true</deleteConflictingFiles>
          <undeployBeforeDeploy>true</undeployBeforeDeploy>
        </configuration>
        <extensions>true</extensions>
      </plugin>
      <plugin>
        <artifactId>maven-compiler-plugin</artifactId>
        <version>3.1</version>
        <configuration>
          <source>1.7</source>
          <target>1.7</target>
        </configuration>
      </plugin>
    </plugins>
  </build>

    <profiles>
        <profile>
            <id>android</id>
            <properties>
                <android.sdk.path>c:/android/sdk</android.sdk.path>
            </properties>
            <activation>
                <activeByDefault>true</activeByDefault>
            </activation>
        </profile>
    </profiles>

</project>