Add ScreenResolutionController to Settings app

Settings for resolution switch

Bug: b/199559703
Test: Check resolution switch UI in Settings app
      atest SettingsUnitTests:ScreenResolutionControllerTest
      atest SettingsUnitTests:ScreenResolutionFragmentTest

Change-Id: I46d3be3b82ca512b8672efaa489df2cdaab26d6d

src/com/android/settings/display/ScreenResolutionController.java

@@ -0,0 +1,87 @@
+/*
+ * Copyright (C) 2022 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.display;
+
+import android.content.Context;
+import android.hardware.display.DisplayManager;
+import android.view.Display;
+
+import androidx.annotation.VisibleForTesting;
+
+import com.android.settings.R;
+import com.android.settings.core.BasePreferenceController;
+
+/** Controller that switch the screen resolution. */
+public class ScreenResolutionController extends BasePreferenceController {
+
+    static final int FHD_WIDTH = 1080;
+    static final int QHD_WIDTH = 1440;
+
+    private Display mDisplay;
+
+    public ScreenResolutionController(Context context, String key) {
+        super(context, key);
+
+        mDisplay =
+                mContext.getSystemService(DisplayManager.class).getDisplay(Display.DEFAULT_DISPLAY);
+    }
+
+    /** Check if the width is supported by the display. */
+    private boolean isSupportedMode(int width) {
+        for (Display.Mode mode : getSupportedModes()) {
+            if (mode.getPhysicalWidth() == width) return true;
+        }
+        return false;
+    }
+
+    /** Return true if the device contains two (or more) resolutions. */
+    protected boolean checkSupportedResolutions() {
+        return isSupportedMode(FHD_WIDTH) && isSupportedMode(QHD_WIDTH);
+    }
+
+    @Override
+    public int getAvailabilityStatus() {
+        return (checkSupportedResolutions()) ? AVAILABLE : UNSUPPORTED_ON_DEVICE;
+    }
+
+    @Override
+    public CharSequence getSummary() {
+        String summary = null;
+        switch (getDisplayWidth()) {
+            case FHD_WIDTH:
+                summary = mContext.getString(R.string.screen_resolution_summary_high);
+                break;
+            case QHD_WIDTH:
+                summary = mContext.getString(R.string.screen_resolution_summary_highest);
+                break;
+            default:
+                summary = mContext.getString(R.string.screen_resolution_title);
+        }
+
+        return summary;
+    }
+
+    @VisibleForTesting
+    public int getDisplayWidth() {
+        return mDisplay.getMode().getPhysicalWidth();
+    }
+
+    @VisibleForTesting
+    public Display.Mode[] getSupportedModes() {
+        return mDisplay.getSupportedModes();
+    }
+}