How can I test fragments with Robolectric?
Support fragments have been moved to module:
shadows-support-v4
(as of July,2015, Robolectric v3.0)
Add a gradle dependency to app/build.gradle:
testCompile 'org.robolectric:shadows-support-v4:3.0'
Then import to your Robolectric test java class:
import org.robolectric.shadows.support.v4.SupportFragmentTestUtil;
Then you can start & use a support-v4 fragment for testing:
@Test
public void minimalFragmentTest() throws Exception {
MyFunFragment fragment = new MyFunFragment();
SupportFragmentTestUtil.startVisibleFragment(fragment);
assertThat(fragment.getView()).isNotNull();
}
References:
- github changelog, moving support fragments to different module
You guys are all doing this the hard way. Just use FragmentTestUtil.
FragmentTestUtil.startFragment(yourfragment);
Edit #4 & #5: In Robolectric 3.*, they split up the fragment starting functions.
For support fragments, you will need to add a dependency to your build.gradle
:
testCompile "org.robolectric:shadows-supportv4:3.8"
Import: org.robolectric.shadows.support.v4.SupportFragmentTestUtil.startFragment;
For platform fragments, you don't need this dependency. Import: import static org.robolectric.util.FragmentTestUtil.startFragment;
They both use the same name of startFragment()
.
import static org.robolectric.shadows.support.v4.SupportFragmentTestUtil.startFragment;
@RunWith(RobolectricTestRunner.class)
@Config(constants = BuildConfig.class)
public class YourFragmentTest
{
@Test
public void shouldNotBeNull() throws Exception
{
YourFragment fragment = YourFragment.newInstance();
startFragment( fragment );
assertNotNull( fragment );
}
}
Edit #3: Robolectric 2.4 has an API for support and regular fragments. You can either use the newInstance()
pattern or use the constructor when constructing your Fragment
's.
import org.junit.Test;
import org.junit.runner.RunWith;
import static org.junit.Assert.assertNotNull;
import static org.robolectric.util.FragmentTestUtil.startFragment;
@RunWith(RobolectricGradleTestRunner.class)
public class YourFragmentTest
{
@Test
public void shouldNotBeNull() throws Exception
{
YourFragment fragment = new YourFragment();
startFragment( fragment );
assertNotNull( fragment );
}
}
Edit #2: There's a new helper if you're using support fragments (one that supports regular activities/fragments should be in the next release):
import static org.robolectric.util.FragmentTestUtil.startFragment;
@Before
public void setUp() throws Exception
{
fragment = YourFragment.newInstance();
startFragment( fragment );
}
Edit: If you upgraded to Robolectric 2.0:
public static void startFragment( Fragment fragment )
{
FragmentActivity activity = Robolectric.buildActivity( FragmentActivity.class )
.create()
.start()
.resume()
.get();
FragmentManager fragmentManager = activity.getSupportFragmentManager();
FragmentTransaction fragmentTransaction = fragmentManager.beginTransaction();
fragmentTransaction.add( fragment, null );
fragmentTransaction.commit();
}
Original answer
As the other commenter suggested, you do need to use the fragment manager (instead of calling the lifecycle methods you listed above).
@RunWith(MyTestRunner.class)
public class YourFragmentTest
{
@Test
public void shouldNotBeNull() throws Exception
{
YourFragment yourFragment = new YourFragment();
startFragment( yourFragment );
assertNotNull( yourFragment );
}
I create a test runner and have a function that starts up a fragment for me so I can use it everywhere.
public class MyTestRunner extends RobolectricTestRunner
{
public MyTestRunner( Class<?> testClass ) throws InitializationError
{
super( testClass );
}
public static void startFragment( Fragment fragment )
{
FragmentManager fragmentManager = new FragmentActivity().getSupportFragmentManager();
FragmentTransaction fragmentTransaction = fragmentManager.beginTransaction();
fragmentTransaction.add( fragment, null );
fragmentTransaction.commit();
}
}
I'm pretty sure you have to create a FragmentTransaction
using the FragmentManager
, then it will work.