ANR簡介

APP出現程序無響應之後，系統通常會向用戶顯示一個對話方塊，這個對話方塊稱作應用程式無響應（ANR：Application Not Responding）對話方塊，使用者可以選擇“等待”而讓程式繼續執行，也可以選擇“強制關閉”，但是無法定位導致出現anr的原因。我們可以通過抓取anr log，幫助我們定位導致APP出現anr的原因。APP執行出現anr的同時，會在data目錄下生成一個 anr 的檔案，anr log儲存在此資料夾下，將其匯出即可。

檢視APP ANR檔案的方法

手機連線USB ,進入CMD命令視窗，輸入以下命令：  >adb shell   $ su  # cd data   # ls  在列出的檔案列表有一個 anr 檔案； 

匯出anr log的方法

進入CMD命令視窗，輸入以下命令：  > adb pull /data/anr/traces.txt D:\   即可將APP生成的anr log檔案匯出到PC D盤根目錄下。 PS：APP生成的anr log儲存在手機/data/anr目錄下的traces.txt檔案裡。

定位ANR異常

log日誌如下： "main" prio=5 tid=1Native| group="main" sCount=1 dsCount=0 obj=0x74a50f90 self=0x7fa197ba00| sysTid=2588 nice=-1 cgrp=top_visible sched=0/0 handle=0x7fa5ebb000

| state=S schedstat=(16137737202215382002428) utm=133 stm=28 core=3 HZ=100| stack=0x7fcc7c8000-0x7fcc7ca000 stackSize=8MB| held mutexes= kernel: __switch_to+0x74/0x8c kernel: futex_wait_queue_me+0xd8/0x168 kernel: futex_wait+0xe4/0x234 kernel: do_futex+0x184/0xa54 kernel:SyS_futex+0x88/0x19c kernel: cpu_switch_to+0x48/0x4cnative

:#00 pc 000000000001cef0/system/lib64/libc.so (syscall+28)native:#01 pc 00000000000679c4/system/lib64/libc.so (_ZL33__pthread_mutex_lock_with_timeoutP24pthread_mutex_internal_tPK8timespeci.constprop.0+260)native:#02 pc 0000000000067d4c/system/lib64/libc.so (pthread_mutex_lock+36)native:#03 pc 00000000000da578/data/app/com.yzxdemo-1/lib/arm64/libUGo.so (_ZN9Conductor26VideoSetSendReciveRotationEjj+44)native:#04 pc 00000000000b4208/data/app/com.yzxdemo-1/lib/arm64/libUGo.so (_Z33me_video_set_send_recive_rotationjj+40)native:#05 pc 000000000006cbbc/data/app/com.yzxdemo-1/oat/arm64/base.odex (int com.gl.softphone.UGoManager.UGoVideoSetSendReciveRotation(int,int)+144)native:#06 pc 000000000006f3a0/data/app/com.yzxdemo-1/oat/arm64/base.odex (int com.gl.softphone.UGoManager.pub_UGoVideoSetSendReciveRotation(int,int)+84)native:#07 pc 000000000008cd88/data/app/com.yzxdemo-1/oat/arm64/base.odex (void com.yzx.api.UCSCall.videoSetSendReciveRotation(int,int)+124)native:#08 pc 0000000000136d3c/data/app/com.yzxdemo-1/oat/arm64/base.odex (void com.yzxdemo.activity.VideoConverseActivity$4.onSensorChanged(android.hardware.SensorEvent)+528)native:#09 pc 0000000000ee5e68/data/dalvik-cache/arm64/[email protected]@boot.oat (???) at com.gl.softphone.UGoManager.UGoVideoSetSendReciveRotation(Native method) at com.gl.softphone.UGoManager.pub_UGoVideoSetSendReciveRotation(UGoManager.java:280)- locked <0x0b2f89b7>(a com.gl.softphone.UGoManager) at com.yzx.api.UCSCall.videoSetSendReciveRotation(UCSCall.java:1050) at com.yzxdemo.activity.VideoConverseActivity$4.onSensorChanged(VideoConverseActivity.java:434) at android.hardware.SystemSensorManager$SensorEventQueue.dispatchSensorEvent(SystemSensorManager.java:496) at android.os.MessageQueue.nativePollOnce(Native method) at android.os.MessageQueue.next(MessageQueue.java:330) at android.os.Looper.loop(Looper.java:137) at android.app.ActivityThread.main(ActivityThread.java:5665) at java.lang.reflect.Method.invoke!(Native method) at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:822) at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:712) 我們從traces.txt異常日誌檔案中匯出了關鍵日誌，其中紅色的這兩行可以定位出問題的所在。