1 /* 2 * Copyright 2024 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 17 package com.android.wm.shell.compatui.letterbox 18 19 import com.android.wm.shell.compatui.letterbox.LetterboxControllerStrategy.LetterboxMode.MULTIPLE_SURFACES 20 import com.android.wm.shell.compatui.letterbox.LetterboxControllerStrategy.LetterboxMode.SINGLE_SURFACE 21 import com.android.wm.shell.dagger.WMSingleton 22 import javax.inject.Inject 23 24 /** 25 * Encapsulate the logic related to the use of a single or multiple surfaces when 26 * implementing letterbox in shell. 27 */ 28 @WMSingleton 29 class LetterboxControllerStrategy @Inject constructor( 30 private val letterboxConfiguration: LetterboxConfiguration 31 ) { 32 33 // Different letterbox implementation modes. 34 enum class LetterboxMode { SINGLE_SURFACE, MULTIPLE_SURFACES } 35 36 @Volatile 37 private var currentMode: LetterboxMode = SINGLE_SURFACE 38 configureLetterboxModenull39 fun configureLetterboxMode() { 40 // TODO(b/377875146): Define criteria for switching between [LetterboxMode]s. 41 // At the moment, we use the presence of rounded corners to understand if to use a single 42 // surface or multiple surfaces for the letterbox areas. This rule will change when 43 // considering transparent activities which won't have rounded corners leading to the 44 // [MULTIPLE_SURFACES] option. 45 // The chosen strategy will depend on performance considerations, 46 // including surface memory usage and the impact of the rounded corners solution. 47 currentMode = if (letterboxConfiguration.isLetterboxActivityCornersRounded()) { 48 SINGLE_SURFACE 49 } else { 50 MULTIPLE_SURFACES 51 } 52 } 53 54 /** 55 * @return The specific mode to use for implementing letterboxing for the given [request]. 56 */ getLetterboxImplementationModenull57 fun getLetterboxImplementationMode(): LetterboxMode = currentMode 58 } 59