How can I shadow the PackageManager with Robolectric

问题:

My Android application has a simple method to fire off an intent to display a URL.

protected void launchBrowser(int id) {     Uri uri = Uri.parse( getString( id ) );     Intent intent = new Intent( ACTION_VIEW, uri);      PackageManager packageManager = getPackageManager();     List activities = packageManager.queryIntentActivities(intent, 0);     if (activities.size() > 0)     {         startActivity(intent);     }     else     {         Toast.makeText(getApplicationContext(),                        "ERROR - no application to display a web page",                        Toast.LENGTH_SHORT).show();     } } 

I'm using Robolectric for unit testing but I'm having trouble verifying this method. Specifically, getPackageManager() is always returning null. How I can shadow the PackageManager? I tried creating a ShadowPackageManager and calling bindShadowClass, but none of my code gets executed - getPackageManager() always returns null. I also tried to Shadow the Application context and return a concrete StubPackageManager, but got the same results. Maybe I've been searching/staring too long - is there a better way to unit test this method?

回答1:

I'm using Robolectric 2.3 for this. As noted in other answers, getPackageManager() does not return null, but shadowApplication.setPackageManager no longer exists.

Since you can't mock PackageManager, you can't give it a list of Intents to resolve for. Fortunately, Robolectric's PackageManager subclass, RobolectricPackageManager, can let you add these intents without a mock:

RobolectricPackageManager rpm = (RobolectricPackageManager)Robolectric.application.getPackageManager(); rpm.addResolveInfoForIntent(new Intent(Settings.ACTION_APPLICATION_DEVELOPMENT_SETTINGS), new ResolveInfo()); 

回答2:

For some reason you need to set the shadow packagemanager manually on your application. Create a custom test runner (by extending RobolectricTestRunner) and override the setApplicationState method:

public class MyTestRunner extends RobolectricTestRunner {      @Override   public void setupApplicationstate(RobolectricConfig robolectricConfig) {      super.setupApplicationState(robolectricConfig);      ShadowApplication shadowApplication = shadowOf(Robolectric.application);      shadowApplication.setPackageName(robolectricConfig.getPackageName());      shadowApplication.setPackageManager(new RobolectricPackageManager(Robolectric.application, robolectricConfig));   } } 

Then specify in your tests that you want to use your own test runner:

@RunWith(MyTestRunner.class) public class MyTest { ... } 

回答3:

I upgraded to the latest Robolectric (version 2.1.1) and the PackageManager doesn't come up null anymore.

The code below verifies that a browser intent is fired (and configured with a url). I haven't tested this on 1.x, but I think it works there too:

@Test public void recipeTitleShouldOpenBrowserOnClick() throws Exception {     title.performClick();     ShadowActivity shadowActivity = shadowOf( detailFragment.getActivity() );     ShadowActivity.IntentForResult intent = shadowActivity.peekNextStartedActivityForResult();      // or     // ShadowActivity.IntentForResult intent = shadowActivity.getNextStartedActivityForResult();      assertThat( intent.intent,                 equalTo( createBrowserIntentWithURL( "url" ) ) ); } 

Note: I'm invoking start activity from a fragment here.

回答4:

Just add on to aleph_null's answer, you can use ShadowResolveInfo.newResolveInfo() to quickly create a mock ResolveInfo ready to be used (I'm using Robolectric 2.4).

RobolectricPackageManager rpm = (RobolectricPackageManager)Robolectric.application.getPackageManager(); rpm.addResolveInfoForIntent(new Intent(Settings.ACTION_APPLICATION_DEVELOPMENT_SETTINGS), ShadowResolveInfo.newResolveInfo(...)); 

回答5:

You can set the ShadowPackageManager in a separate method (without extending RobolectricTestRunner)

private void setupPackageManager() {     ShadowApplication shadowApplication = shadowOf(Robolectric.application);     shadowApplication.setPackageManager(mockPackageManager);     List activities = new ArrayList();     activities.add(resolveInfo("com.test.package.Class1"));     activities.add(resolveInfo("com.test.package.Class2"));     when(mockPackageManager.queryIntentActivities(any(Intent.class), anyInt())).thenReturn(activities); } 

Note : Here, i have used mockito & mocked the packagemanager for my unittest instead of using the actual PackageManager.

回答6:

For Robolectric 3.1 you can

RobolectricPackageManager packageManager = RuntimeEnvironment.getRobolectricPackageManager(); // add necessary logic here 

文章来源: How can I shadow the PackageManager with Robolectric