Create a preference controller for "App info"

We try to avoid managing too many preferences in a controller.
So, we create another controller to manage all apps info preference.

RecentAppsPreferenceController and AllAppsInfoPreferenceController
share same state of recent apps in order to improve the performance.

Test: visual, robo test
Fixes: 126134996
Change-Id: I1d8a175b213831415797437c64fd9d432864f9d3

src/com/android/settings/applications/AllAppsInfoPreferenceController.java

@@ -0,0 +1,58 @@
+/*
+ * Copyright (C) 2019 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.applications;
+
+import android.app.usage.UsageStats;
+import android.content.Context;
+
+import androidx.preference.Preference;
+
+import com.android.settings.R;
+import com.android.settings.core.BasePreferenceController;
+
+import java.util.List;
+
+public class AllAppsInfoPreferenceController extends BasePreferenceController {
+
+    private List<UsageStats> mRecentApps;
+
+    public AllAppsInfoPreferenceController(Context context, String key) {
+        super(context, key);
+    }
+
+    public void setRecentApps(List<UsageStats> recentApps) {
+        mRecentApps = recentApps;
+    }
+
+    @Override
+    public int getAvailabilityStatus() {
+        return mRecentApps == null || mRecentApps.isEmpty() ? AVAILABLE : CONDITIONALLY_UNAVAILABLE;
+    }
+
+    @Override
+    public void updateState(Preference preference) {
+        super.updateState(preference);
+        // Show total number of installed apps as See all's summary.
+        new InstalledAppCounter(mContext, InstalledAppCounter.IGNORE_INSTALL_REASON,
+                mContext.getPackageManager()) {
+            @Override
+            protected void onCountComplete(int num) {
+                preference.setSummary(mContext.getString(R.string.apps_summary, num));
+            }
+        }.execute();
+    }
+}