如何在android中对这行LayoutInflater.from()进行单元测试
您好,我正在构建一个简单的RecycleView适配器,我正在尝试测试适配器的所有方法,但是onCreateViewHolder对我来说很困难如何在android中对这行LayoutInflater.from()进行单元测试,android,unit-testing,tdd,Android,Unit Testing,Tdd,您好,我正在构建一个简单的RecycleView适配器,我正在尝试测试适配器的所有方法,但是onCreateViewHolder对我来说很困难 @Override public NewsViewHolder onCreateViewHolder(ViewGroup parent, int viewType) { View v = LayoutInflater.from(parent.getContext()).inflate(R.layout.fragment_news,parent,
@Override
public NewsViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View v = LayoutInflater.from(parent.getContext()).inflate(R.layout.fragment_news,parent,false);
return new NewsViewHolder(v);
}
我尝试使用mockito构建viewGroup类的模拟,并在调用getContext()时返回MockContext的间谍,但似乎是因为我返回的是MockContext LayoutFlater。from()返回空指针异常
这是我的测试
@Test
public void testOnCreateViewHolder() throws Exception {
ViewGroup vg = mock(ViewGroup.class);
MockContext mockContext = new MockContext();
MockContext spyContext = spy(mockContext);
when(vg.getContext()).thenReturn(spyContext);
NewsViewHolder vh = adapter.onCreateViewHolder(vg, 0);
Assert.assertNotNull("Response cant be null",vh);
}
提前谢谢。我遇到这个问题时,我也是同样的问题。最后我自己解决了 假设您有一个简单的
onCreateViewHolder
,如下所示:
@Override
public TeamsViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
return new NewsViewHolder(LayoutInflater
.from(parent.getContext())
.inflate(R.layout.fragment_news_view_holder, parent, false)
);
}
使用PowerMock
模拟LayoutInflater
的静态实例。在下面的代码段中,我已经使用编号注释说明了为实现此功能所需的所有步骤:
import android.test.mock.MockContext;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import org.junit.Before;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.mockito.Mock;
import org.mockito.MockitoAnnotations;
import org.powermock.core.classloader.annotations.PrepareForTest;
import org.powermock.modules.junit4.PowerMockRunner;
import static junit.framework.Assert.assertEquals;
import static junit.framework.Assert.assertNotNull;
import static org.mockito.Matchers.anyInt;
import static org.mockito.Matchers.eq;
import static org.mockito.Mockito.when;
import static org.powermock.api.mockito.PowerMockito.mockStatic;
// 1. signal JUnit to run this test PowerMockRunner
@RunWith(PowerMockRunner.class)
// 2. signal PowerMock to prepare the static instance of LayoutInflater for testing
@PrepareForTest({LayoutInflater.class})
public class NewsRecyclerViewAdapterTest {
// 3. LayoutInflater.from(context) returns an inflater,
// so we need to mock that one
@Mock
LayoutInflater mockInflater;
@Mock
View mockView;
@Mock
ViewGroup mockParent;
private int dummyTestId;
private MockContext mockContext;
private NewsRecyclerViewAdapter adapter;
@Before
public void setUp() throws Exception {
MockitoAnnotations.initMocks(this);
dummyTestId = 0x10000;
// 4. mock the static LayoutInflater in "LayoutInflater.from()"
// so that we can ask it to return a mockInflater that we moked above
mockStatic(LayoutInflater.class);
mockContext = new MockContext();
adapter = new NewsRecyclerViewAdapter(Arrays.asList(new NewsItem(), new NewsItem(), new NewsItem()));
}
@Test
public void onCreateViewHolderShouldReturnAValidViewHolder() throws Exception {
// 5. mock the context that comes from parent ViewGroup
when(mockParent.getContext()).thenReturn(mockContext);
// 6. mock the inflater that is returned by LayoutInflater.from()
when(LayoutInflater.from(mockContext)).thenReturn(mockInflater);
// 7. pass anyInt() as a resource id to care of R.layout.fragment_news_view_holder in onCreateViewHolder()
when(mockInflater.inflate(anyInt(), eq(mockParent), eq(false))).thenReturn(mockView);
// call onCreateViewHolder() to act
NewsViewHolder viewHolder = adapter.onCreateViewHolder(mockParent, dummyTestId);
// OKAY straightfoward right?
assertNotNull(viewHolder);
// this is not very important but I recommend it,
// it just returns the view sent to NewsViewHolder
// and verify it against the mockView that you inflated above
assertEquals(viewHolder.getItemView(), mockView);
}
}
你得到答案了吗?没有,我的朋友最后公司决定测试这个功能,作为一个集成测试,非常好的一步一步的解释!