android oreo / pie - paho mqtt无法在后台启动活动

Question

我正在尝试解决在android pie（9.0）上运行的paho mqtt。

我在Service类中运行我的mqtt连接（返回START_STICKY）并使用bind连接到UI ...所有工作都很好但是什么不工作是当应用程序被杀死时，Service和mqtt连接停止。 Mqtt AlarmPingSender停止工作..试图在Nougat（7.0）上测试它并且它的工作非常好。

有没有一个解决方案让mqtt paho库在新版本的Android上运行？

logcat的：

2019-03-22 02:35:08.854 12651-12651/com.example.dominik.smarthome2 E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.example.dominik.smarthome2, PID: 12651
java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.dominik.smarthome2/com.example.dominik.smarthome2.MainActivity}: java.lang.IllegalStateException: Not allowed to start service Intent { cmp=com.example.dominik.smarthome2/.MyService }: app is in background uid UidRecord{ee07604 u0a297 TPSL idle procs:1 proclist:12651, seq(0,0,0)}
    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:3108)
    at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3251)
    at android.app.servertransaction.LaunchActivityItem.execute(LaunchActivityItem.java:78)
    at android.app.servertransaction.TransactionExecutor.executeCallbacks(TransactionExecutor.java:108)
    at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:68)
    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1948)
    at android.os.Handler.dispatchMessage(Handler.java:106)
    at android.os.Looper.loop(Looper.java:214)
    at android.app.ActivityThread.main(ActivityThread.java:7045)
    at java.lang.reflect.Method.invoke(Native Method)
    at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:493)
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:964)
 Caused by: java.lang.IllegalStateException: Not allowed to start service Intent { cmp=com.example.dominik.smarthome2/.MyService }: app is in background uid UidRecord{ee07604 u0a297 TPSL idle procs:1 proclist:12651, seq(0,0,0)}
    at android.app.ContextImpl.startServiceCommon(ContextImpl.java:1666)
    at android.app.ContextImpl.startService(ContextImpl.java:1611)
    at android.content.ContextWrapper.startService(ContextWrapper.java:677)
    at com.example.dominik.smarthome2.MainActivity.onCreate(MainActivity.java:122)
    at android.app.Activity.performCreate(Activity.java:7327)
    at android.app.Activity.performCreate(Activity.java:7318)
    at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1271)
    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:3088)
    at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3251) 
    at android.app.servertransaction.LaunchActivityItem.execute(LaunchActivityItem.java:78) 
    at android.app.servertransaction.TransactionExecutor.executeCallbacks(TransactionExecutor.java:108) 
    at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:68) 
    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1948) 
    at android.os.Handler.dispatchMessage(Handler.java:106) 
    at android.os.Looper.loop(Looper.java:214) 
    at android.app.ActivityThread.main(ActivityThread.java:7045) 
    at java.lang.reflect.Method.invoke(Native Method) 
    at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:493) 
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:964)   

Answer 1

Android 8.0引入了Background Execution Limits，因此您应该使用startForegroundService()而不是startService()来运行具有可见通知的Foreground Service：