java - Android单元测试: Mock context that also returns a looper

Question

这是我的示例代码:
SomeClass.java

public class SomeClass {
    public SomeClass(Context mContext) {
        final Looper looper = mContext.getMainLooper();
        Handler mHandler = new Handler(looper);
    }
}

SomeClassTest.java

public class SomeClassTest {
    private SomeClass mSomeClass;

    @Mock
    private Context mContext;

    @before
    public void setup(){
        mSomeClass = new SomeClass(mContext);
    }
}

上面的代码在SomeClass中的final Looper Looper = mContext.getMainLooper();行生成了一个NullPointerException。
如何设置模拟上下文对象以避免此异常？

Answer 1

假设您正在使用 Mockito，您可以向模拟对象添加模拟行为:

public class SomeClassTest {
    private SomeClass mSomeClass;
    private Looper mLooper;

    @before
    public void setup(){
        mLooper = mock(Looper.class);
        Context ctx = mock(Context.class);
        when(ctx.getMainLooper()).thenReturn(mLooper);
        mSomeClass = new SomeClass(mContext);
    }
}