1 /* 2 * Copyright (C) 2017 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 package com.android.wallpaper.util; 17 18 import android.content.res.Configuration; 19 import android.content.res.Resources; 20 import android.util.DisplayMetrics; 21 import android.util.Log; 22 import android.view.Display; 23 24 /** 25 * Retrieves copies of DisplayMetrics from Display objects and caches them in memory. All clients 26 * that need a copy of DisplayMetrics should use this retriever class to avoid excessive binder 27 * calls to the system server. 28 */ 29 public class DisplayMetricsRetriever { 30 31 private static final String TAG = "DisplayMetricsRetriever"; 32 33 private static DisplayMetricsRetriever sInstance; 34 35 private DisplayMetrics mPortraitDisplayMetrics; 36 private DisplayMetrics mLandscapeDisplayMetrics; 37 getInstance()38 public static DisplayMetricsRetriever getInstance() { 39 if (sInstance == null) { 40 sInstance = new DisplayMetricsRetriever(); 41 } 42 return sInstance; 43 } 44 45 /** 46 * Clears the static instance of DisplayMetricsRetriever. Used in test when display metrics are 47 * manipulated between test cases. 48 */ clearInstance()49 static void clearInstance() { 50 sInstance = null; 51 } 52 53 /** 54 * Returns the DisplayMetrics for the provided Display. 55 */ getDisplayMetrics(Resources resources, Display display)56 public DisplayMetrics getDisplayMetrics(Resources resources, Display display) { 57 switch (resources.getConfiguration().orientation) { 58 case Configuration.ORIENTATION_PORTRAIT: 59 return getPortraitDisplayMetrics(display); 60 case Configuration.ORIENTATION_LANDSCAPE: 61 return getLandscapeDisplayMetrics(display); 62 default: 63 Log.e(TAG, "Unknown device orientation: " + resources.getConfiguration().orientation); 64 return getPortraitDisplayMetrics(display); 65 } 66 } 67 getPortraitDisplayMetrics(Display display)68 private DisplayMetrics getPortraitDisplayMetrics(Display display) { 69 if (mPortraitDisplayMetrics == null) { 70 mPortraitDisplayMetrics = new DisplayMetrics(); 71 writeDisplayMetrics(display, mPortraitDisplayMetrics); 72 } 73 return mPortraitDisplayMetrics; 74 } 75 getLandscapeDisplayMetrics(Display display)76 private DisplayMetrics getLandscapeDisplayMetrics(Display display) { 77 if (mLandscapeDisplayMetrics == null) { 78 mLandscapeDisplayMetrics = new DisplayMetrics(); 79 writeDisplayMetrics(display, mLandscapeDisplayMetrics); 80 } 81 return mLandscapeDisplayMetrics; 82 } 83 writeDisplayMetrics(Display display, DisplayMetrics outMetrics)84 private void writeDisplayMetrics(Display display, DisplayMetrics outMetrics) { 85 display.getMetrics(outMetrics); 86 } 87 } 88