log visibility of views

Depends-On: I5b1dccb5d103ece3112acf38889bae16273b092f
Change-Id: I116aed2bb805f723a5bf2ec9eb94257de0b4a7b5

src/com/android/settings/InstrumentedFragment.java

@@ -0,0 +1,39 @@
+/*
+ * Copyright (C) 2015 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;
+
+import android.preference.PreferenceFragment;
+import com.android.internal.logging.MetricsLogger;
+
+/**
+ * Instrumented fragment that logs visibility state.
+ */
+public abstract class InstrumentedFragment extends PreferenceFragment {
+    protected abstract int getMetricsCategory();
+
+    @Override
+    public void onResume() {
+        super.onResume();
+        MetricsLogger.visible(getActivity(), getMetricsCategory());
+    }
+
+    @Override
+    public void onPause() {
+        super.onPause();
+        MetricsLogger.hidden(getActivity(), getMetricsCategory());
+    }
+}