[Testing] Use AndroidJUnit4 instead in GlobalSettingsChangeListenerTest

1. Use AndroidJunit4 instead of RobolectricTestRunner
2. Use ApplicationProvider instead of RuntimeEnvironment to get context
3. Add new TestListener for spy GlobalSettingsChangeListener

Bug: 163299183
Test: atest -c GlobalSettingsChangeListenerTest
Change-Id: I0290470d3d3b235e0069ecbb9c1ce87a705d71d1

tests/unit/src/com/android/settings/network/GlobalSettingsChangeListenerTest.java

@@ -0,0 +1,97 @@
+/*
+ * Copyright (C) 2020 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 com.android.settings.network;
+
+import static org.mockito.Mockito.doNothing;
+import static org.mockito.Mockito.spy;
+import static org.mockito.Mockito.times;
+import static org.mockito.Mockito.verify;
+
+import android.content.Context;
+import android.os.Looper;
+import android.provider.Settings;
+
+import androidx.lifecycle.Lifecycle;
+import androidx.test.core.app.ApplicationProvider;
+import androidx.test.ext.junit.runners.AndroidJUnit4;
+
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.mockito.Mock;
+import org.mockito.MockitoAnnotations;
+
+@RunWith(AndroidJUnit4.class)
+public class GlobalSettingsChangeListenerTest {
+
+    @Mock
+    private Lifecycle mLifecycle;
+
+    private Context mContext;
+    private TestListener mTestListener;
+
+    private static final String SETTINGS_FIELD = Settings.Global.AIRPLANE_MODE_ON;
+
+    public class TestListener extends GlobalSettingsChangeListener {
+        TestListener(Looper looper, Context context, String field) {
+            super(looper, context, field);
+        }
+        @Override
+        public void onChanged(String field) {}
+    }
+
+    @Before
+    public void setUp() {
+        MockitoAnnotations.initMocks(this);
+        mContext = spy(ApplicationProvider.getApplicationContext());
+        mTestListener = spy(new TestListener(Looper.getMainLooper(), mContext, SETTINGS_FIELD));
+
+        doNothing().when(mLifecycle).addObserver(mTestListener);
+        doNothing().when(mLifecycle).removeObserver(mTestListener);
+    }
+
+    /*
+     * The method onChange is override from {@link ContentObserver}, and when the content change
+     * occurs will be called. And the method onChanged is subclass from
+     * {@link GlobalSettingsChangeListener}, it will be called when the onChange be called.
+     */
+    @Test
+    public void whenChanged_onChangedBeenCalled() {
+        mTestListener.onChange(false);
+
+        verify(mTestListener, times(1)).onChanged(SETTINGS_FIELD);
+    }
+
+    @Test
+    public void whenNotifyChangeBasedOnLifecycle_onStopEvent_onChangedNotCalled() {
+        mTestListener.notifyChangeBasedOn(mLifecycle);
+        mTestListener.onStart();
+
+        mTestListener.onChange(false);
+        verify(mTestListener, times(1)).onChanged(SETTINGS_FIELD);
+
+        mTestListener.onStop();
+
+        mTestListener.onChange(false);
+        verify(mTestListener, times(1)).onChanged(SETTINGS_FIELD);
+
+        mTestListener.onStart();
+
+        mTestListener.onChange(false);
+        verify(mTestListener, times(2)).onChanged(SETTINGS_FIELD);
+    }
+}