Android ANR

1）什麼引發了ANR？

在Android裏，應用程序的響應性是由Activity Manager和WindowManager系統服務監視的。當它監測到以下情況中的一個時，Android就會針對特定的應用程序顯示ANR：

在5秒內沒有響應輸入的事件（例如，按鍵按下，屏幕觸摸）
BroadcastReceiver在10秒內沒有執行完畢

一個ANR對話框顯示給用戶

2）如何避免ANR？

考慮上面的ANR定義，讓我們來研究一下爲什麼它會在Android應用程序裏發生和如何最佳構建應用程序來避免ANR。

Android應用程序通常是運行在一個單獨的線程（例如，main）裏。這意味着你的應用程序所做的事情如果在主線程裏佔用了太長的時間的話，就會引發ANR對話框，因爲你的應用程序並沒有給自己機會來處理輸入事件或者Intent廣播。

因此，運行在主線程裏的任何方法都儘可能少做事情。特別是，Activity應該在它的關鍵生命週期方法（如onCreate()和onResume()）裏儘可能少的去做創建操作。潛在的耗時操作，例如網絡或數據庫操作，或者高耗時的計算如改變位圖尺寸，應該在子線程裏（或者以數據庫操作爲例，通過異步請求的方式）來完成。然而，不是說你的主線程阻塞在那裏等待子線程的完成——也不是調用Thread.wait()或是Thread.sleep()。替代的方法是，主線程應該爲子線程提供一個Handler，以便完成時能夠提交給主線程。以這種方式設計你的應用程序，將能保證你的主線程保持對輸入的響應性並能避免由於5秒輸入事件的超時引發的ANR對話框。這種做法應該在其它顯示UI的線程裏效仿，因爲它們都受相同的超時影響。

IntentReceiver執行時間的特殊限制意味着它應該做：在後臺裏做小的、瑣碎的工作如保存設定或者註冊一個Notification。和在主線程裏調用的其它方法一樣，應用程序應該避免在BroadcastReceiver裏做耗時的操作或計算。但不再是在子線程裏做這些任務（因爲BroadcastReceiver的生命週期短），替代的是，如果響應Intent廣播需要執行一個耗時的動作的話，應用程序應該啓動一個Service。順便提及一句，你也應該避免在IntentReceiver裏啓動一個Activity，因爲它會創建一個新的畫面，並從當前用戶正在運行的程序上搶奪焦點。如果你的應用程序在響應Intent廣播時需要向用戶展示什麼，你應該使用Notification Manager來實現。

3）增強響應靈敏性

一般來說，在應用程序裏，100到200ms是用戶能感知阻滯的時間閾值。因此，這裏有一些額外的技巧來避免ANR，並有助於讓你的應用程序看起來有響應性。

如果你的應用程序爲響應用戶輸入正在後臺工作的話，可以顯示工作的進度（ProgressBar和ProgressDialog對這種情況來說很有用）。
特別是遊戲，在子線程裏做移動的計算。
如果你的應用程序有一個耗時的初始化過程的話，考慮可以顯示一個SplashScreen或者快速顯示主畫面並異步來填充這些信息。在這兩種情況下，你都應該顯示正在進行的進度，以免用戶認爲應用程序被凍結了。

15:59:37 I/ActivityManager(130): ANR in process: com.android.email(last in com.android.email)

=>frameworks\base\services\java\com\android\server\am\ActivityManagerService.java
=>提示輸出cpu信息

Annotation: keyDispatchingTimedOut
CPU usage:

=>frameworks\base\services\java\com\android\server\ProcessStats.java
=>輸出cpu當前狀態

=>/proc/loadavg 顯示cpu負荷
=>1-分鐘平均負載 / 5-分鐘平均負載 / 15-分鐘平均負載

Load: 4.37 /4.55 / 3.97
=>cpu狀態的時間段
CPU usage from 10987ms to 27ms ago:

=>/proc/state讀取cpu的使用情況
=>http://linux.die.net/man/5/proc
=>user
=>kernel
=>iowait
=>irq ->0
=>softirq ->0
=>minor

The number of minor faults the process has madewhich have not required loading a memory page fromdisk.

=>major

The number of major faults the process has madewhich have required loading a memory page from disk.

system_server: 12% = 4% user + 7% kernel /faults: 1886 minor
m.android.email: 12% = 6% user + 5% kernel /faults: 2716 minor
sensorserver_ya: 7% = 0% user + 7%kernel
breeze.launcher: 3% = 0% user + 3% kernel /faults: 94 minor
ocess.msn.shell: 0% = 0% user + 0% kernel /faults: 38 minor
m.android.phone: 0% = 0% user + 0%kernel
alog: 0% = 0% user + 0% kernel
rpcrotuer_smd_x: 0% = 0% user + 0%kernel
rild: 0% = 0% user + 0% kernel
alog: 0% = 0% user + 0% kernel
events/0: 0% = 0% user + 0% kernel
port-bridge: 0% = 0% user + 0% kernel
TOTAL: 81% = 13% user + 25% kernel + 42% iowait

15:59:37 I/ActivityManager(130): Removing old ANR trace file from/data/anr/traces.txt

Android ANR這個錯誤大家並不陌生，但是從Android2.2開始出錯的ANR信息會自動上傳給Google進行系統分析改進，當然了你的應用ANR錯誤其實保存在一個文件中，在/data/anr/traces.txt文件中.
下面一起來分析下錯誤吧，第一行爲出錯的時間，第二行都會寫上發生ANR的packageName，下文是com.android.systemui這個包，裏面的部分線程出了問題，通過下面的的xxx方法以及對應的java文件，後面的數字爲xxx.java文件的第幾行，是不是很方便呢?

----- pid 125 at 2011-02-22 05:18:01 -----
Cmd line: com.android.systemui

DALVIK THREADS:
(mutexes: tll=0 tsl=0 tscl=0 ghl=0 hwl=0 hwll=0)
"main" prio=5 tid=1 NATIVE
| group="main" sCount=1 dsCount=0 obj=0x4001f1a8self=0xce48
| sysTid=125 nice=0 sched=0/0 cgrp=defaulthandle=-1345006528
| schedstat=( 981213067 8042604425 151 )
at android.os.BinderProxy.transact(NativeMethod)
atandroid.os.storage.IMountService$Stub$Proxy.isUsbMassStorageConnected(IMountService.java:95)
atandroid.os.storage.StorageManager.isUsbMassStorageConnected(StorageManager.java:385)
atcom.android.systemui.usb.StorageNotification.<init>(StorageNotification.java:71)
atcom.android.systemui.statusbar.policy.StatusBarPolicy.<init>(StatusBarPolicy.java:412)
atcom.android.systemui.statusbar.StatusBarService.onCreate(StatusBarService.java:239)
atandroid.app.ActivityThread.handleCreateService(ActivityThread.java:1920)
atandroid.app.ActivityThread.access$2500(ActivityThread.java:117)
atandroid.app.ActivityThread$H.handleMessage(ActivityThread.java:982)
atandroid.os.Handler.dispatchMessage(Handler.java:99)
at android.os.Looper.loop(Looper.java:123)
atandroid.app.ActivityThread.main(ActivityThread.java:3647)
at java.lang.reflect.Method.invokeNative(NativeMethod)
atjava.lang.reflect.Method.invoke(Method.java:507)
atcom.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:839)
atcom.android.internal.os.ZygoteInit.main(ZygoteInit.java:597)
at dalvik.system.NativeStart.main(NativeMethod)

"Binder Thread #2" prio=5 tid=8 NATIVE
| group="main" sCount=1 dsCount=0 obj=0x40511270self=0x1c1100
| sysTid=153 nice=0 sched=0/0 cgrp=defaulthandle=1141608
| schedstat=( 27181321 64708345 5 )
at dalvik.system.NativeStart.run(NativeMethod)

"Binder Thread #1" prio=5 tid=7 NATIVE
| group="main" sCount=1 dsCount=0 obj=0x405111a8self=0x1349c8
| sysTid=152 nice=0 sched=0/0 cgrp=defaulthandle=1264008
| schedstat=( 31857510 74284459 5 )
at dalvik.system.NativeStart.run(NativeMethod)

"Compiler" daemon prio=5 tid=6 VMWAIT
| group="system" sCount=1 dsCount=0obj=0x4050dd10 self=0x116538
| sysTid=144 nice=0 sched=0/0 cgrp=defaulthandle=982520
| schedstat=( 7319346 103454345 12 )
at dalvik.system.NativeStart.run(NativeMethod)

"JDWP" daemon prio=5 tid=5 VMWAIT
| group="system" sCount=1 dsCount=0obj=0x4050dc60 self=0x116400
| sysTid=142 nice=0 sched=0/0 cgrp=defaulthandle=986536
| schedstat=( 32876840 393298925 20 )
at dalvik.system.NativeStart.run(NativeMethod)

"Signal Catcher" daemon prio=5 tid=4 RUNNABLE
| group="system" sCount=0 dsCount=0obj=0x4050dba0 self=0x253ab0
| sysTid=141 nice=0 sched=0/0 cgrp=defaulthandle=2439792
| schedstat=( 94447996 796994478 19 )
at dalvik.system.NativeStart.run(NativeMethod)

"GC" daemon prio=5 tid=3 VMWAIT
| group="system" sCount=1 dsCount=0obj=0x4050daf8 self=0x8fd40
| sysTid=128 nice=0 sched=0/0 cgrp=defaulthandle=2439592
| schedstat=( 103352102 819201761 21 )
at dalvik.system.NativeStart.run(NativeMethod)

"HeapWorker" daemon prio=5 tid=2 VMWAIT
| group="system" sCount=1 dsCount=0obj=0x4050da40 self=0xf0c70
| sysTid=127 nice=0 sched=0/0 cgrp=defaulthandle=2439528
| schedstat=( 971134410 6445300652 103 )
at dalvik.system.NativeStart.run(NativeMethod)

二：ANR的常見類型

ANR一般有三種類型：

1：KeyDispatchTimeout(5 seconds) --主要類型

按鍵或觸摸事件在特定時間內無響應

2：BroadcastTimeout(10 seconds)

BroadcastReceiver在特定時間內無法處理完成

3：ServiceTimeout(20 seconds) --小概率類型

Service在特定的時間內無法處理完成

三：KeyDispatchTimeout

Akey or touch event was not dispatched within the specified time（按鍵或觸摸事件在特定時間內無響應）

具體的超時時間的定義在framework下的

ActivityManagerService.java

//How long we wait until we timeout on key dispatching.

staticfinal int KEY_DISPATCHING_TIMEOUT = 5*1000

四：爲什麼會超時呢？

超時時間的計數一般是從按鍵分發給app開始。超時的原因一般有兩種：

(1)當前的事件沒有機會得到處理（即UI線程正在處理前一個事件，沒有及時的完成或者looper被某種原因阻塞住了）

(2)當前的事件正在處理，但沒有及時完成

五：如何避免KeyDispatchTimeout

1：UI線程儘量只做跟UI相關的工作

2：耗時的工作（比如數據庫操作，I/O，連接網絡或者別的有可能阻礙UI線程的操作）把它放入單獨的線程處理

3：儘量用Handler來處理UIthread和別的thread之間的交互

六：UI線程

說了那麼多的UI線程，那麼哪些屬於UI線程呢？

UI線程主要包括如下：

Activity:onCreate(), onResume(), onDestroy(), onKeyDown(), onClick(),etc
AsyncTask: onPreExecute(), onProgressUpdate(), onPostExecute(), onCancel,etc
Mainthread handler: handleMessage(), post*(runnable r), etc
other

七:如何去分析ANR

先看個LOG:

04-01 13:12:11.572 I/InputDispatcher( 220): Application is not responding:Window{2b263310com.android.email/com.android.email.activity.SplitScreenActivitypaused=false}. 5009.8ms since event, 5009.5ms since waitstarted

04-0113:12:11.572 I/WindowManager( 220): Input event dispatching timedout sending tocom.android.email/com.android.email.activity.SplitScreenActivity

04-01 13:12:14.123 I/Process( 220): Sending signal. PID: 21404 SIG: 3---發生ANR的時間和生成trace.txt的時間

04-01 13:12:14.123 I/dalvikvm(21404):threadid=4: reacting to signal 3

……

04-0113:12:15.872 E/ActivityManager( 220): ANR in com.android.email(com.android.email/.activity.SplitScreenActivity)

04-0113:12:15.872 E/ActivityManager( 220): Reason:keyDispatchingTimedOut

04-0113:12:15.872 E/ActivityManager( 220): Load: 8.68 / 8.37 / 8.53

04-0113:12:15.872 E/ActivityManager( 220):CPUusage from 4361ms to 699ms ago----CPU在ANR發生前的使用情況

04-0113:12:15.872 E/ActivityManager( 220): 5.5%21404/com.android.email: 1.3% user + 4.1% kernel / faults: 10 minor

04-0113:12:15.872 E/ActivityManager( 220): 4.3%220/system_server: 2.7% user + 1.5% kernel / faults: 11 minor 2 major

04-0113:12:15.872 E/ActivityManager( 220): 0.9%52/spi_qsd.0: 0% user + 0.9% kernel

04-0113:12:15.872 E/ActivityManager( 220): 0.5%65/irq/170-cyttsp-: 0% user + 0.5% kernel

04-0113:12:15.872 E/ActivityManager( 220): 0.5%296/com.android.systemui: 0.5% user + 0% kernel

04-0113:12:15.872 E/ActivityManager( 220): 100%TOTAL: 4.8% user + 7.6% kernel + 87% iowait

04-0113:12:15.872 E/ActivityManager( 220):CPUusage from 3697ms to 4223ms later:-- ANR後CPU的使用量

04-0113:12:15.872 E/ActivityManager( 220): 25%21404/com.android.email: 25% user + 0% kernel / faults: 191 minor

04-0113:12:15.872 E/ActivityManager( 220): 16% 21603/__eas(par.hakan: 16% user + 0% kernel

04-0113:12:15.872 E/ActivityManager( 220): 7.2% 21406/GC: 7.2% user + 0% kernel

04-0113:12:15.872 E/ActivityManager( 220): 1.8% 21409/Compiler: 1.8% user + 0% kernel

04-0113:12:15.872 E/ActivityManager( 220): 5.5%220/system_server: 0% user + 5.5% kernel / faults: 1 minor

04-0113:12:15.872 E/ActivityManager( 220): 5.5% 263/InputDispatcher: 0% user + 5.5% kernel

04-0113:12:15.872 E/ActivityManager( 220): 32%TOTAL: 28% user + 3.7% kernel

從LOG可以看出ANR的類型，CPU的使用情況，如果CPU使用量接近100%，說明當前設備很忙，有可能是CPU飢餓導致了ANR

如果CPU使用量很少，說明主線程被BLOCK了

如果IOwait很高，說明ANR有可能是主線程在進行I/O操作造成的

除了看LOG，解決ANR還得需要trace.txt文件，

如何獲取呢？可以用如下命令獲取

$chmod 777 /data/anr
$rm /data/anr/traces.txt
$ps
$kill -3PID
adbpull data/anr/traces.txt ./mytraces.txt

從trace.txt文件，看到最多的是如下的信息：

-----pid 21404 at 2011-04-0113:12:14 -----
Cmdline: com.android.email

DALVIK THREADS:
(mutexes: tll=0tsl=0 tscl=0 ghl=0 hwl=0 hwll=0)
"main" prio=5 tid=1NATIVE
| group="main" sCount=1 dsCount=0obj=0x2aad2248 self=0xcf70
| sysTid=21404 nice=0 sched=0/0cgrp=[fopen-error:2] handle=1876218976
atandroid.os.MessageQueue.nativePollOnce(Native Method)
atandroid.os.MessageQueue.next(MessageQueue.java:119)
atandroid.os.Looper.loop(Looper.java:110)
at android.app.ActivityThread.main(ActivityThread.java:3688)
at java.lang.reflect.Method.invokeNative(Native Method)
atjava.lang.reflect.Method.invoke(Method.java:507)
atcom.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:866)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:624)
at dalvik.system.NativeStart.main(Native Method)

說明主線程在等待下條消息進入消息隊列

八：Thread狀態

ThreadState (defined at “dalvik/vm/thread.h “)

THREAD_UNDEFINED = -1, /* makes enum compatible with int32_t */

THREAD_ZOMBIE = 0, /* TERMINATED */

THREAD_RUNNING = 1, /* RUNNABLE or running now */

THREAD_TIMED_WAIT = 2, /* TIMED_WAITING in Object.wait() */

THREAD_MONITOR = 3, /* BLOCKED on a monitor */

THREAD_WAIT = 4, /* WAITING in Object.wait() */

THREAD_INITIALIZING= 5, /* allocated, not yet running */

THREAD_STARTING = 6, /* started, not yet on thread list */

THREAD_NATIVE = 7, /* off in a JNI native method */

THREAD_VMWAIT = 8, /* waiting on a VM resource */

THREAD_SUSPENDED = 9, /* suspended, usually by GC or debugger */

九：如何調查並解決ANR

1：首先分析log

2: 從trace.txt文件查看調用stack.

3: 看代碼

4：仔細查看ANR的成因（iowait?block?memoryleak?）

十：案例

案例1：關鍵詞:ContentResolver in AsyncTask onPostExecute, high iowait

Process:com.android.email
Activity:com.android.email/.activity.MessageView
Subject:keyDispatchingTimedOut
CPU usage from 2550ms to -2814ms ago:
5%187/system_server: 3.5% user + 1.4% kernel / faults: 86 minor 20major
4.4% 1134/com.android.email: 0.7% user + 3.7% kernel /faults: 38 minor 19 major
4% 372/com.android.eventstream: 0.7%user + 3.3% kernel / faults: 6 minor
1.1% 272/com.android.phone:0.9% user + 0.1% kernel / faults: 33 minor
0.9%252/com.android.systemui: 0.9% user + 0% kernel
0%409/com.android.eventstream.telephonyplugin: 0% user + 0% kernel /faults: 2 minor
0.1% 632/com.android.devicemonitor: 0.1% user + 0%kernel
100%TOTAL: 6.9% user + 8.2% kernel +84%iowait

-----pid 1134 at 2010-12-17 17:46:51 -----
Cmd line:com.android.email

DALVIK THREADS:
(mutexes: tll=0 tsl=0tscl=0 ghl=0 hwl=0 hwll=0)
"main" prio=5 tid=1 WAIT
|group="main" sCount=1 dsCount=0 obj=0x2aaca180self=0xcf20
| sysTid=1134 nice=0 sched=0/0 cgrp=[fopen-error:2]handle=1876218976
at java.lang.Object.wait(Native Method)
-waiting on <0x2aaca218> (a java.lang.VMThread)
atjava.lang.Thread.parkFor(Thread.java:1424)
atjava.lang.LangAccessImpl.parkFor(LangAccessImpl.java:48)
atsun.misc.Unsafe.park(Unsafe.java:337)
atjava.util.concurrent.locks.LockSupport.park(LockSupport.java:157)
atjava.util.concurrent.locks.AbstractQueuedSynchronizer.parkAndCheckInterrupt(AbstractQueuedSynchronizer.java:808)
atjava.util.concurrent.locks.AbstractQueuedSynchronizer.acquireQueued(AbstractQueuedSynchronizer.java:841)
atjava.util.concurrent.locks.AbstractQueuedSynchronizer.acquire(AbstractQueuedSynchronizer.java:1171)
atjava.util.concurrent.locks.ReentrantLock$FairSync.lock(ReentrantLock.java:200)
atjava.util.concurrent.locks.ReentrantLock.lock(ReentrantLock.java:261)
atandroid.database.sqlite.SQLiteDatabase.lock(SQLiteDatabase.java:378)
atandroid.database.sqlite.SQLiteCursor.<init>(SQLiteCursor.java:222)
atandroid.database.sqlite.SQLiteDirectCursorDriver.query(SQLiteDirectCursorDriver.java:53)
atandroid.database.sqlite.SQLiteDatabase.rawQueryWithFactory(SQLiteDatabase.java:1356)
atandroid.database.sqlite.SQLiteDatabase.queryWithFactory(SQLiteDatabase.java:1235)
atandroid.database.sqlite.SQLiteDatabase.query(SQLiteDatabase.java:1189)
atandroid.database.sqlite.SQLiteDatabase.query(SQLiteDatabase.java:1271)
atcom.android.email.provider.EmailProvider.query(EmailProvider.java:1098)
atandroid.content.ContentProvider$Transport.query(ContentProvider.java:187)
atandroid.content.ContentResolver.query(ContentResolver.java:268)
atcom.android.email.provider.EmailContent$Message.restoreMessageWithId(EmailContent.java:648)
atcom.android.email.Controller.setMessageRead(Controller.java:658)
atcom.android.email.activity.MessageView.onMarkAsRead(MessageView.java:700)
atcom.android.email.activity.MessageView.access$2500(MessageView.java:98)
atcom.android.email.activity.MessageView$LoadBodyTask.onPostExecute(MessageView.java:1290)
atcom.android.email.activity.MessageView$LoadBodyTask.onPostExecute(MessageView.java:1255)
atandroid.os.AsyncTask.finish(AsyncTask.java:417)
atandroid.os.AsyncTask.access$300(AsyncTask.java:127)
atandroid.os.AsyncTask$InternalHandler.handleMessage(AsyncTask.java:429)
atandroid.os.Handler.dispatchMessage(Handler.java:99)
atandroid.os.Looper.loop(Looper.java:123)
atandroid.app.ActivityThread.main(ActivityThread.java:3652)
atjava.lang.reflect.Method.invokeNative(Native Method)
atjava.lang.reflect.Method.invoke(Method.java:507)
atcom.android.internal.os.ZygoteIn

原因：IOWait很高，說明當前系統在忙於I/O，因此數據庫操作被阻塞

原來：

finalMessagemessage=Message.restoreMessageWithId(mProviderContext,messageId);
if(message==null){
   return;
}

Accountaccount=Account.restoreAccountWithId(mProviderContext,message.mAccountKey);

if(account==null){
   return;//isMessagingController returns false for null, but let's make itclear.
}

if(isMessagingController(account)){
   new Thread(){
       @Override
       public void run(){
          mLegacyController.processPendingActions(message.mAccountKey);
       }
   }.start();
}

解決後：

newThread() {
    finalMessagemessage=Message.restoreMessageWithId(mProviderContext,messageId);

    if(message==null){
        return;
    }

    Accountaccount=Account.restoreAccountWithId(mProviderContext,message.mAccountKey);

    if(account==null){
       return;//isMessagingController returns false for null, but let's make itclear.
    }

    if(isMessagingController(account)) {
        mLegacyController.processPendingActions(message.mAccountKey);
    }
}.start();

關於AsyncTask:http://developer.android.com/reference/android/os/AsyncTask.html

案例2：關鍵詞:在UI線程進行網絡數據的讀寫

ANRin process: com.android.mediascape:PhotoViewer (last incom.android.mediascape:PhotoViewer)
Annotation:keyDispatchingTimedOut
CPU usage:
Load: 6.74 / 6.89 / 6.12
CPUusage from 8254ms to 3224ms ago:
ovider.webmedia: 4% = 4% user +0% kernel / faults: 68 minor
system_server: 2% = 1% user + 0%kernel / faults: 18 minor
re-initialized>: 0% = 0% user + 0%kernel / faults: 50 minor
events/0: 0% = 0% user + 0%kernel
TOTAL:7% = 6% user + 1% kernel

DALVIKTHREADS:
""main"" prio=5 tid=3 NATIVE
|group=""main"" sCount=1 dsCount=0 s=Yobj=0x4001b240 self=0xbda8
| sysTid=2579 nice=0 sched=0/0cgrp=unknown handle=-1343993184
atorg.apache.harmony.luni.platform.OSNetworkSystem.receiveStreamImpl(NativeMethod)
atorg.apache.harmony.luni.platform.OSNetworkSystem.receiveStream(OSNetworkSystem.java:478)
atorg.apache.harmony.luni.net.PlainSocketImpl.read(PlainSocketImpl.java:565)
atorg.apache.harmony.luni.net.SocketInputStream.read(SocketInputStream.java:87)
atorg.apache.harmony.luni.internal.net.www.protocol.http.HttpURLConnection$LimitedInputStream.read(HttpURLConnection.java:303)
atjava.io.InputStream.read(InputStream.java:133)
atjava.io.BufferedInputStream.fillbuf(BufferedInputStream.java:157)
atjava.io.BufferedInputStream.read(BufferedInputStream.java:346)
atandroid.graphics.BitmapFactory.nativeDecodeStream(Native Method)
atandroid.graphics.BitmapFactory.decodeStream(BitmapFactory.java:459)
atcom.android.mediascape.activity.PhotoViewerActivity.getPreviewImage(PhotoViewerActivity.java:4465)
atcom.android.mediascape.activity.PhotoViewerActivity.dispPreview(PhotoViewerActivity.java:4406)
atcom.android.mediascape.activity.PhotoViewerActivity.access$6500(PhotoViewerActivity.java:125)
atcom.android.mediascape.activity.PhotoViewerActivity$33$1.run(PhotoViewerActivity.java:4558)
atandroid.os.Handler.handleCallback(Handler.java:587)
atandroid.os.Handler.dispatchMessage(Handler.java:92)
atandroid.os.Looper.loop(Looper.java:123)
atandroid.app.ActivityThread.main(ActivityThread.java:4370)
atjava.lang.reflect.Method.invokeNative(Native Method)
atjava.lang.reflect.Method.invoke(Method.java:521)
atcom.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:868)
atcom.android.internal.os.ZygoteInit.main(ZygoteInit.java:626)
atdalvik.system.NativeStart.main(Native Method)

關於網絡連接，在設計的時候可以設置個timeout的時間或者放入獨立的線程來處理。

關於Handler的問題，可以參考：http://developer.android.com/reference/android/os/Handler.html

案例3：

關鍵詞：Memoryleak/Thread leak

11-1621:41:42.560 I/ActivityManager( 1190): ANR in process:android.process.acore (last in android.process.acore)
11-1621:41:42.560 I/ActivityManager( 1190): Annotation:keyDispatchingTimedOut
11-16 21:41:42.560 I/ActivityManager(1190): CPU usage:
11-16 21:41:42.560 I/ActivityManager( 1190):Load: 11.5 / 11.1 / 11.09
11-16 21:41:42.560 I/ActivityManager(1190): CPU usage from 9046ms to 4018ms ago:
11-16 21:41:42.560I/ActivityManager( 1190): d.process.acore:98%= 97% user + 0% kernel / faults: 1134 minor
11-16 21:41:42.560I/ActivityManager( 1190): system_server: 0% = 0% user + 0% kernel /faults: 1 minor
11-16 21:41:42.560 I/ActivityManager( 1190): adbd:0% = 0% user + 0% kernel
11-16 21:41:42.560 I/ActivityManager(1190): logcat: 0% = 0% user + 0% kernel
11-16 21:41:42.560I/ActivityManager( 1190): TOTAL:100% = 98% user + 1% kernel

Cmdline: android.process.acore

DALVIK THREADS:
"main"prio=5 tid=3 VMWAIT
|group="main" sCount=1 dsCount=0 s=N obj=0x40026240self=0xbda8
| sysTid=1815 nice=0 sched=0/0 cgrp=unknownhandle=-1344001376
atdalvik.system.VMRuntime.trackExternalAllocation(NativeMethod)
atandroid.graphics.Bitmap.nativeCreate(Native Method)
atandroid.graphics.Bitmap.createBitmap(Bitmap.java:468)
atandroid.view.View.buildDrawingCache(View.java:6324)
atandroid.view.View.getDrawingCache(View.java:6178)
atandroid.view.ViewGroup.drawChild(ViewGroup.java:1541)
……
atcom.android.internal.policy.impl.PhoneWindow$DecorView.draw(PhoneWindow.java:1830)
atandroid.view.ViewRoot.draw(ViewRoot.java:1349)
atandroid.view.ViewRoot.performTraversals(ViewRoot.java:1114)
atandroid.view.ViewRoot.handleMessage(ViewRoot.java:1633)
atandroid.os.Handler.dispatchMessage(Handler.java:99)
atandroid.os.Looper.loop(Looper.java:123)
atandroid.app.ActivityThread.main(ActivityThread.java:4370)
atjava.lang.reflect.Method.invokeNative(Native Method)
atjava.lang.reflect.Method.invoke(Method.java:521)
atcom.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:868)
atcom.android.internal.os.ZygoteInit.main(ZygoteInit.java:626)
atdalvik.system.NativeStart.main(Native Method)

"Thread-408"prio=5 tid=329 WAIT
|group="main" sCount=1 dsCount=0 s=N obj=0x46910d40self=0xcd0548
| sysTid=10602 nice=0 sched=0/0 cgrp=unknownhandle=15470792
at java.lang.Object.wait(Native Method)
-waiting on <0x468cd420> (a java.lang.Object)
atjava.lang.Object.wait(Object.java:288)
atcom.android.dialer.CallLogContentHelper$UiUpdaterExecutor$1.run(CallLogContentHelper.java:289)
atjava.lang.Thread.run(Thread.java:1096)

分析：

atdalvik.system.VMRuntime.trackExternalAllocation(NativeMethod)內存不足導致block在創建bitmap上

**MEMINFO in pid 1360 [android.process.acore] **
native dalvik other total
size: 17036 23111 N/A 40147
allocated: 16484 20675 N/A 37159
free: 296 2436 N/A 2732

解決：如果機器的內存族，可以修改虛擬機的內存爲36M或更大，不過最好是複查代碼，查看哪些內存沒有釋放

案例1：關鍵詞:ContentResolver in AsyncTask onPostExecute, high iowait

案例2：關鍵詞:在UI線程進行網絡數據的讀寫

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