Dianne Hackborn | 8d044e8 | 2013-04-30 17:24:15 -0700 | [diff] [blame^] | 1 | /* |
| 2 | * Copyright (C) 2013 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.server; |
| 18 | |
| 19 | import android.os.Handler; |
| 20 | import android.os.HandlerThread; |
| 21 | import android.os.StrictMode; |
| 22 | import android.util.Slog; |
| 23 | |
| 24 | /** |
| 25 | * Shared singleton thread for showing UI. This is a foreground thread, and in |
| 26 | * additional should not have operations that can take more than a few ms scheduled |
| 27 | * on it to avoid UI jank. |
| 28 | */ |
| 29 | public final class UiThread extends HandlerThread { |
| 30 | private static UiThread sInstance; |
| 31 | private static Handler sHandler; |
| 32 | |
| 33 | private UiThread() { |
| 34 | super("android.ui", android.os.Process.THREAD_PRIORITY_FOREGROUND); |
| 35 | } |
| 36 | |
| 37 | private static void ensureThreadLocked() { |
| 38 | if (sInstance == null) { |
| 39 | sInstance = new UiThread(); |
| 40 | sInstance.start(); |
| 41 | sHandler = new Handler(sInstance.getLooper()); |
| 42 | sHandler.post(new Runnable() { |
| 43 | @Override |
| 44 | public void run() { |
| 45 | //Looper.myLooper().setMessageLogging(new LogPrinter( |
| 46 | // Log.VERBOSE, "WindowManagerPolicy", Log.LOG_ID_SYSTEM)); |
| 47 | android.os.Process.setCanSelfBackground(false); |
| 48 | |
| 49 | // For debug builds, log event loop stalls to dropbox for analysis. |
| 50 | if (StrictMode.conditionallyEnableDebugLogging()) { |
| 51 | Slog.i("UiThread", "Enabled StrictMode logging for UI thread"); |
| 52 | } |
| 53 | } |
| 54 | }); |
| 55 | } |
| 56 | } |
| 57 | |
| 58 | public static UiThread get() { |
| 59 | synchronized (UiThread.class) { |
| 60 | ensureThreadLocked(); |
| 61 | return sInstance; |
| 62 | } |
| 63 | } |
| 64 | |
| 65 | public static Handler getHandler() { |
| 66 | synchronized (UiThread.class) { |
| 67 | ensureThreadLocked(); |
| 68 | return sHandler; |
| 69 | } |
| 70 | } |
| 71 | } |