FragmentController { @Nullable public Fragment findCurrentFragment() { this.assertNotDestroyed("FIND CURRENT FRAGMENT"); if (viewContainerId == NO_CONTAINER_ID) { throw new UnsupportedOperationException("Cannot find current fragment. No fragment container id specified!"); } return manager.findFragmentById(viewContainerId); } FragmentController(@NonNull final FragmentActivity parentActivity);  FragmentController(@NonNull final Fragment parentFragment);  FragmentController(@NonNull final FragmentManager fragmentManager);  FragmentController(@Nullable final Context context, @NonNull final FragmentManager fragmentManager); @NonNull FragmentManager getFragmentManager(); void setViewContainerId(@IdRes final int containerId); @IdRes int getViewContainerId(); void setFactory(@Nullable final FragmentFactory factory); boolean hasFactory(); @Nullable FragmentFactory getFactory(); void setRequestInterceptor(@Nullable final FragmentRequestInterceptor interceptor); void registerOnRequestListener(@NonNull final OnRequestListener listener); void unregisterOnRequestListener(@NonNull final OnRequestListener listener); void registerOnBackStackChangeListener(@NonNull final OnBackStackChangeListener listener); void unregisterOnBackStackChangeListener(@NonNull final OnBackStackChangeListener listener); @NonNull final FragmentRequest newRequest(); @NonNull final FragmentRequest newRequest(@NonNull final Fragment fragment); @NonNull final FragmentRequest newRequest(final int fragmentId); @SuppressWarnings("NewApi") @NonNull FragmentTransaction createTransaction(@NonNull final FragmentRequest request); @Nullable Fragment findCurrentFragment(); @Nullable Fragment findFragmentByFactoryId(final int factoryFragmentId); boolean hasBackStackEntries(); @Nullable FragmentManager.BackStackEntry getTopBackStackEntry(); void clearBackStack(); boolean clearBackStackImmediate(); final void destroy(); static final String FRAGMENT_TAG; static final int NO_CONTAINER_ID; }
@Test public void testFindCurrentFragment() { final FragmentManager mockManager = mock(FragmentManager.class); final Fragment mockFragment = mock(TestFragment.class); final FragmentController controller = new FragmentController(mockManager); controller.setViewContainerId(TestActivity.CONTENT_VIEW_ID); when(mockManager.findFragmentById(controller.getViewContainerId())).thenReturn(mockFragment); assertThat(controller.findCurrentFragment(), is(mockFragment)); verify(mockManager).findFragmentById(controller.getViewContainerId()); }
@Test(expected = UnsupportedOperationException.class) public void testFindCurrentFragmentWithoutViewContainerIdSpecified() { final FragmentController controller = new FragmentController(mock(FragmentManager.class)); controller.findCurrentFragment(); }
@Test(expected = IllegalStateException.class) public void testFindCurrentFragmentWhenDestroyed() { createDestroyedController().findCurrentFragment(); }