经过一番研究,我终于解决了这个问题。
Android 提供了一些在测试中使用的类,例如 MockContext、IsolatedContext。
http://developer.android.com/reference/android/test/mock/MockContext.html http://developer.android.com/reference/android/test/mock/MockContext.html
http://developer.android.com/reference/android/test/IsolatedContext.html http://developer.android.com/reference/android/test/IsolatedContext.html
为了完成此任务,我创建了 ContextWrapper 的子类并覆盖(??) getSystemService 方法。
根据文档:
“Context 的代理实现,只需将其所有调用委托给另一个 Context。可以进行子类化以修改行为,而无需更改原始 Context。”
http://developer.android.com/reference/android/content/ContextWrapper.html http://developer.android.com/reference/android/content/ContextWrapper.html
这样,我在 Activity 中使用常规 AndroidActivityUnitTestCase 注入了原始上下文,但进行了修改以满足我的需求。
看一下这个:
public class FakeContextWrapper extends ContextWrapper {
private static final String ACCOUNT_TYPE = "com.example.android";
private static final Account ACCOUNT_1 = new Account("[email protected] /cdn-cgi/l/email-protection", ACCOUNT_TYPE);
private static final Account ACCOUNT_2 = new Account("[email protected] /cdn-cgi/l/email-protection", ACCOUNT_TYPE);
private static final Account[] TWO_ACCOUNTS = { ACCOUNT_1, ACCOUNT_2 };
@Mock
private AccountManager mMockAccountManager;
public FakeContextWrapper(Context base) {
super(base);
MockitoAnnotations.initMocks(this);
Mockito.when(mMockAccountManager.getAccounts()).thenReturn(TWO_ACCOUNTS);
}
@Override
public Object getSystemService(String name) {
if (Context.ACCOUNT_SERVICE.equals(name)) {
return mMockAccountManager;
} else {
return super.getSystemService(name);
}
}
}
测试内部:
public void testAccountNotFound() {
Context context = new FakeContextWrapper(getInstrumentation().getTargetContext());
setActivityContext(context);
Intent intent = new Intent(Intent.ACTION_MAIN);
startActivity(intent, null, null);
// TODO assertions.
}
最后,测试的 Activity:
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_pressures_list);
AccountManager am = AccountManager.get(this);
Account[] accounts = am.getAccounts();
if (accounts.length == 0) {
// TODO call login.
} else {
Log.i("TAG", "it works!");
}
}