1 /* 2 * Copyright (C) 2021 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.systemui.flags 17 18 /** 19 * Plugin for loading flag values 20 */ 21 interface FlagListenable { 22 /** Add a listener to be alerted when the given flag changes. */ addListenernull23 fun addListener(flag: Flag<*>, listener: Listener) 24 25 /** Remove a listener to be alerted when any flag changes. */ 26 fun removeListener(listener: Listener) 27 28 /** A simple listener to be alerted when a flag changes. */ 29 fun interface Listener { 30 /** Called when the flag changes */ 31 fun onFlagChanged(event: FlagEvent) 32 } 33 34 /** An event representing the change */ 35 interface FlagEvent { 36 /** the id of the flag which changed */ 37 val flagName: String 38 /** if all listeners alerted invoke this method, the restart will be skipped */ requestNoRestartnull39 fun requestNoRestart() 40 } 41 }