fragment/src/androidTest/java/android/support/v4/app/LoaderViewModelTest.java

/*
 * Copyright 2018 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package android.support.v4.app;

import static org.junit.Assert.assertFalse;
import static org.junit.Assert.assertTrue;

import android.content.Context;
import android.support.test.filters.SmallTest;
import android.support.test.rule.ActivityTestRule;
import android.support.test.runner.AndroidJUnit4;
import android.support.v4.app.test.LoaderActivity;

import org.junit.Rule;
import org.junit.Test;
import org.junit.runner.RunWith;

@RunWith(AndroidJUnit4.class)
@SmallTest
public class LoaderViewModelTest {

    @Rule
    public ActivityTestRule<LoaderActivity> mActivityRule =
            new ActivityTestRule<>(LoaderActivity.class);

    @Test
    public void testHasRunningLoaders() {
        LoaderManagerImpl.LoaderViewModel loaderViewModel = new LoaderManagerImpl.LoaderViewModel();
        assertFalse("LoaderViewModel should not be running with before putLoader",
                loaderViewModel.hasRunningLoaders());

        AlwaysRunningLoaderInfo info = new AlwaysRunningLoaderInfo(mActivityRule.getActivity());
        loaderViewModel.putLoader(0, info);
        assertTrue("LoaderViewModel should be running after a running LoaderInfo is added",
                loaderViewModel.hasRunningLoaders());

        loaderViewModel.removeLoader(0);
        assertFalse("LoaderViewModel should not be running after all LoaderInfos are removed",
                loaderViewModel.hasRunningLoaders());
    }

    @Test
    public void testOnCleared() {
        LoaderManagerImpl.LoaderViewModel loaderViewModel = new LoaderManagerImpl.LoaderViewModel();
        AlwaysRunningLoaderInfo info = new AlwaysRunningLoaderInfo(
                mActivityRule.getActivity());
        loaderViewModel.putLoader(0, info);

        assertFalse("LoaderInfo shouldn't be destroyed before onCleared", info.mDestroyed);
        loaderViewModel.onCleared();
        assertTrue("LoaderInfo should be destroyed after onCleared", info.mDestroyed);
    }

    private class AlwaysRunningLoaderInfo extends LoaderManagerImpl.LoaderInfo<Boolean> {
        boolean mDestroyed = false;

        AlwaysRunningLoaderInfo(Context context) {
            super(0, null, new LoaderTest.DummyLoader(context));
        }

        @Override
        boolean isCallbackWaitingForData() {
            return true;
        }

        @Override
        void destroy() {
            mDestroyed = true;
        }
    }
}