Log visibility change for all fragments.

Bug: 30681771
Test: SettingsUnitTests

Refactor visibility logging from InstrumentedFragment into a mixin. And
apply mixin in remaining fragments.

Change-Id: Ibbb59904336254a3e4bb9e8c7d0b36e5a6bc2622

src/com/android/settings/core/InstrumentedActivity.java

@@ -0,0 +1,42 @@
+/*
+ * Copyright (C) 2016 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.core;
+
+import android.app.Activity;
+
+import com.android.settings.core.instrumentation.Instrumentable;
+import com.android.settings.core.instrumentation.VisibilityLoggerMixin;
+
+/**
+ * Instrumented activity that logs visibility state.
+ */
+public abstract class InstrumentedActivity extends Activity implements Instrumentable {
+
+    private final VisibilityLoggerMixin mVisibilityLoggerMixin = new VisibilityLoggerMixin(this);
+
+    @Override
+    public void onResume() {
+        super.onResume();
+        mVisibilityLoggerMixin.onResume(this);
+    }
+
+    @Override
+    public void onPause() {
+        super.onPause();
+        mVisibilityLoggerMixin.onPause(this);
+    }
+}

src/com/android/settings/core/InstrumentedFragment.java

@@ -0,0 +1,47 @@
+/*
+ * Copyright (C) 2016 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.core;
+
+import android.os.Bundle;
+import android.support.v14.preference.PreferenceFragment;
+
+import com.android.settings.core.instrumentation.VisibilityLoggerMixin;
+import com.android.settings.core.instrumentation.Instrumentable;
+
+/**
+ * Instrumented fragment that logs visibility state.
+ */
+public abstract class InstrumentedFragment extends PreferenceFragment implements Instrumentable {
+
+    private final VisibilityLoggerMixin mVisibilityLoggerMixin = new VisibilityLoggerMixin(this);
+
+    @Override
+    public void onCreatePreferences(Bundle savedInstanceState, String rootKey) {
+    }
+
+    @Override
+    public void onResume() {
+        super.onResume();
+        mVisibilityLoggerMixin.onResume(getActivity());
+    }
+
+    @Override
+    public void onPause() {
+        super.onPause();
+        mVisibilityLoggerMixin.onPause(getActivity());
+    }
+}

src/com/android/settings/core/instrumentation/EventLogWriter.java

@@ -0,0 +1,59 @@
+/*
+ * Copyright (C) 2016 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.core.instrumentation;
+
+import android.content.Context;
+
+import com.android.internal.logging.MetricsLogger;
+
+/**
+ * Pass-through Metrics logger for {@link MetricsLogger}.
+ */
+public class EventLogWriter {
+
+    public void visible(Context context, int category) {
+        MetricsLogger.visible(context, category);
+    }
+
+    public void hidden(Context context, int category) {
+        MetricsLogger.hidden(context, category);
+    }
+
+    public void action(Context context, int category) {
+        MetricsLogger.action(context, category, "");
+    }
+
+    public void action(Context context, int category, int value) {
+        MetricsLogger.action(context, category, Integer.toString(value));
+    }
+
+    public void action(Context context, int category, boolean value) {
+        MetricsLogger.action(context, category, Boolean.toString(value));
+    }
+
+    public void action(Context context, int category, String pkg) {
+        MetricsLogger.action(context, category, pkg);
+    }
+
+    public void count(Context context, String name, int value) {
+        MetricsLogger.count(context, name, value);
+    }
+
+    public void histogram(Context context, String name, int bucket) {
+        MetricsLogger.histogram(context, name, bucket);
+    }
+}

src/com/android/settings/core/instrumentation/Instrumentable.java

@@ -0,0 +1,26 @@
+/*
+ * Copyright (C) 2016 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.core.instrumentation;
+
+public interface Instrumentable {
+
+    /**
+     * Instrumented name for a view as defined in
+     * {@link com.android.internal.logging.MetricsProto.MetricsEvent}.
+     */
+    int getMetricsCategory();
+}

src/com/android/settings/core/instrumentation/MetricsFactory.java

@@ -0,0 +1,38 @@
+/*
+ * Copyright (C) 2016 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.core.instrumentation;
+
+public class MetricsFactory {
+
+    private static MetricsFactory sInstance;
+
+    private EventLogWriter mLogger;
+
+    public static MetricsFactory get() {
+        if (sInstance == null) {
+            sInstance = new MetricsFactory();
+        }
+        return sInstance;
+    }
+
+    public EventLogWriter getLogger() {
+        if (mLogger == null) {
+            mLogger = new EventLogWriter();
+        }
+        return mLogger;
+    }
+}

src/com/android/settings/core/instrumentation/VisibilityLoggerMixin.java

@@ -0,0 +1,45 @@
+/*
+ * Copyright (C) 2016 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.core.instrumentation;
+
+import android.content.Context;
+
+/**
+ * Logs visibility change of a fragment.
+ */
+public class VisibilityLoggerMixin {
+
+    private final Instrumentable mInstrumentable;
+    private final EventLogWriter mEventLogWriter;
+
+    public VisibilityLoggerMixin(Instrumentable instrumentable) {
+        this(instrumentable, MetricsFactory.get().getLogger());
+    }
+
+    public VisibilityLoggerMixin(Instrumentable instrumentable, EventLogWriter eventLogWriter) {
+        mInstrumentable = instrumentable;
+        mEventLogWriter = eventLogWriter;
+    }
+
+    public void onResume(Context context) {
+        mEventLogWriter.visible(context, mInstrumentable.getMetricsCategory());
+    }
+
+    public void onPause(Context context) {
+        mEventLogWriter.hidden(context, mInstrumentable.getMetricsCategory());
+    }
+}