Question

我已经实现了Content Provider，它从网络上安装的服务中检索数据。内容提供者从共享首选项（用户凭据，应用程序名称等）中获取所需参数

SharedPreferences settings = getContext().getSharedPreferences(NET_PREFS, 0);

我对此内容提供商使用单元测试：


public class ResearchProviderTest extends ProviderTestCase2<MyProvider>{

    public ResearchProviderTest() {     
        super(MyProvider.class, MyProvider.CONTENT_AUTHORITY);
    }

    public void testInsert() {

        ContentValues values = new ContentValues();        
        values.put(QueryFields.FIELD_QUERY_TEXT, "query" );

        Uri newUri = getMockContentResolver().insert(MyProvider.CONTENT_URI, values);

        Cursor readMessagesCursor = getMockContentResolver().query(
                newUri ,
                        new String[] { FIELD_SR_TITLE }, 
                        null, null, null );
        assertTrue("The cursor should contain some entries", readMessagesCursor.moveToFirst());
    }
}

执行单元测试期间。抛出异常：


java.lang.UnsupportedOperationException
   at android.test.mock.MockContext.getSharedPreferences(MockContext.java:127)
   at android.content.ContextWrapper.getSharedPreferences(ContextWrapper.java:146)
   at android.content.ContextWrapper.getSharedPreferences(ContextWrapper.java:146)
   at com.company.mobile.android.net.RemoteExecutor.retrieveCredentials(RemoteExecutor.java:171)
   at com.company.mobile.android.net.service.Adapter.executeSearch(Adapter.java:33)
   at com.company.mobile.android.provider.MyProvider.insert(MyProvider.java:167)
   at android.content.ContentProvider$Transport.insert(ContentProvider.java:174)
   ...

有人知道如何将共享首选项传递给MockContext吗？如果在测试Content Provider期间需要Context，我应该使用其他方法吗？

Answer 1

您必须使用AndroidTestCase.setContext()注入Context MockContext，并至少覆盖getPackageName()和getSharedPreferences()。

不幸的是，不可能将MockContext注入ProviderTestCase2，因为setContext（）不受尊重。然后，解决方案是覆盖setUp()而不是调用super方法。

package com.example.aatg.ps.test;

import android.test.ProviderTestCase2;

import com.example.aatg.ps.ProviderSample;

public class ProviderSampleTests extends ProviderTestCase2<ProviderSample> {

    private ResolverRenamingMockContext mProviderContext;
    private Class<ProviderSample> mProviderClass;
    private ProviderSample mProvider;
    private String mProviderAuthority;

    public ProviderSampleTests() {
        super(ProviderSample.class, ProviderSample.AUTHORITY);
        setName("ProviderSampleTests");
        mProviderClass = ProviderSample.class;
        mProviderAuthority = ProviderSample.AUTHORITY;
    }

    @Override
    protected void setUp() throws Exception {
         // We should not invoke super.setUp() here to avoid the UnsupportedOperationException.
        //super.setUp();

        // This is needed to support getSharedPreferences() in ProviderSample.onCreate()
        mProviderContext = new ResolverRenamingMockContext(getContext());
        mProvider = mProviderClass.newInstance();
        assertNotNull(mProvider);
        mProvider.attachInfo(mProviderContext, null);
        mProviderContext.addProvider(mProviderAuthority, mProvider);
    }


    @Override
    public ProviderSample getProvider() {
        return mProvider;
    }

    protected void tearDown() throws Exception {
        super.tearDown();
    }

    public void testProviderSampleCreation() {
        ProviderSample provider = getProvider();
        assertNotNull(provider);
    }
}

这是ResolverRenamingMockContext：

package com.example.aatg.ps.test;

import java.io.File;

import android.content.ContentProvider;
import android.content.Context;
import android.content.SharedPreferences;
import android.content.res.Resources;
import android.test.IsolatedContext;
import android.test.mock.MockContentResolver;
import android.test.mock.MockContext;

/**
 * @author diego
 *
 */
public class ResolverRenamingMockContext extends IsolatedContext {

    /**
     * The renaming prefix.
     */
    private static final String PREFIX = "test.";


    /**
     * The resolver.
     */
    private static final MockContentResolver RESOLVER = new MockContentResolver();

    /**
     * Constructor.
     * @param context 
     */
    public ResolverRenamingMockContext(Context context) {
        super(RESOLVER, new DelegatedMockContext(context));
    }

    public MockContentResolver getResolver() {
        return RESOLVER;
    }

    public void addProvider(String name, ContentProvider provider) {
        RESOLVER.addProvider(name, provider);
    }

    /**
     * The DelegatedMockContext.
     *
     */
    private static class DelegatedMockContext extends MockContext {

        private Context mDelegatedContext;

        public DelegatedMockContext(Context context) {
            mDelegatedContext = context;
        }

        @Override
        public SharedPreferences getSharedPreferences(String name, int mode) {
            return mDelegatedContext.getSharedPreferences(PREFIX + name, mode);
        }
    }

}

Answer 2

只需展开AndroidTestCase而不是ProviderTestCase2并使用getContext()

Answer 3

您可以重构内容提供商，将共享首选项的所有用途推送到MyHelper类。

默认MyHelper实现可以像使用现在一样使用共享首选项，并通过getter返回所需的值。

在测试期间，您可以注入一个特殊的MyHelper实现，一个不使用共享首选项的实现。也许它被称为TestingHelper它只返回由测试定义的常量。

例如，在ResearchProviderTest：

中

@Override
protected void setUp() throws Exception {
    // set up normally
    super.setUp();

    // inject a special helper for testing
    MyProvider provider = (MyProvider) getProvider();
    provider.setHelper(new TestingHelper());
}

从单元测试中调用getSharedPreferences（）时出现UnsupportedOperationException

3 个答案: