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 17package com.android.server; 18 19import static android.os.Process.THREAD_PRIORITY_DISPLAY; 20 21import android.os.Handler; 22import android.os.Trace; 23 24/** 25 * Thread for handling all window animations, or anything that's directly impacting animations like 26 * starting windows or traversals. 27 */ 28public final class AnimationThread extends ServiceThread { 29 private static AnimationThread sInstance; 30 private static Handler sHandler; 31 32 private AnimationThread() { 33 super("android.anim", THREAD_PRIORITY_DISPLAY, false /*allowIo*/); 34 } 35 36 private static void ensureThreadLocked() { 37 if (sInstance == null) { 38 sInstance = new AnimationThread(); 39 sInstance.start(); 40 sInstance.getLooper().setTraceTag(Trace.TRACE_TAG_WINDOW_MANAGER); 41 sHandler = new Handler(sInstance.getLooper()); 42 } 43 } 44 45 public static AnimationThread get() { 46 synchronized (AnimationThread.class) { 47 ensureThreadLocked(); 48 return sInstance; 49 } 50 } 51 52 public static Handler getHandler() { 53 synchronized (AnimationThread.class) { 54 ensureThreadLocked(); 55 return sHandler; 56 } 57 } 58} 59