1 /* 2 * Copyright (C) 2022 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.systemui.settings 18 19 import android.view.Display 20 import java.util.concurrent.Executor 21 22 /** 23 * Display tracker for SystemUI. 24 * 25 * This tracker provides async access to display information, as well as callbacks for display 26 * changes. 27 */ 28 interface DisplayTracker { 29 30 /** The id for the default display for the current SystemUI instance. */ 31 val defaultDisplayId: Int 32 33 /** All displays that should be associated with the current SystemUI instance. */ 34 val allDisplays: Array<Display> 35 36 /** 37 * Add a [Callback] to be notified of display changes, including additions, removals, and 38 * configuration changes, on a particular [Executor]. 39 */ addDisplayChangeCallbacknull40 fun addDisplayChangeCallback(callback: Callback, executor: Executor) 41 42 /** 43 * Add a [Callback] to be notified of display brightness changes, on a particular [Executor]. 44 * This callback will trigger Callback#onDisplayChanged for a display brightness change. 45 */ 46 fun addBrightnessChangeCallback(callback: Callback, executor: Executor) 47 48 /** Remove a [Callback] previously added. */ 49 fun removeCallback(callback: Callback) 50 51 /** Ćallback for notifying of changes. */ 52 interface Callback { 53 54 /** Notifies that a display has been added. */ 55 @JvmDefault fun onDisplayAdded(displayId: Int) {} 56 57 /** Notifies that a display has been removed. */ 58 @JvmDefault fun onDisplayRemoved(displayId: Int) {} 59 60 /** Notifies a display has been changed */ 61 @JvmDefault fun onDisplayChanged(displayId: Int) {} 62 } 63 } 64