调用活动 onStart 时，应用程序似乎在后台

Question

从 Android Oreo 开始，当应用不在前台时，您无法启动服务。在我的应用程序中，我在活动的 onStart 方法中启动了一项服务。这在大多数情况下都可以正常工作。但是，有时会抛出 IllegalStateException，说明应用程序正在后台尝试启动服务：

    java.lang.IllegalStateException: Not allowed to start service Intent { act=ui cmp=com.someapp/.services.ConnectionService }: app is in background uid UidRecord{8d70361 u0a255 TPSL bg:+3m12s948ms idle change:cached procs:1 proclist:20368, 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.someapp.ui.SomeActivity.connectToBackend(SomeActivity.java:62)
    at com.someapp.ui.SomeActivity.onStart(SomeActivity.java:55)
    at com.someapp.ui.MainActivity.onStart(MainActivity.kt:228)
    at android.app.Instrumentation.callActivityOnStart(Instrumentation.java:1391)
    at android.app.Activity.performStart(Activity.java:7348)
    at android.app.ActivityThread.handleStartActivity(ActivityThread.java:3131)
    at android.app.servertransaction.TransactionExecutor.performLifecycleSequence(TransactionExecutor.java:180)
    at android.app.servertransaction.TransactionExecutor.cycleToPath(TransactionExecutor.java:165)
    at android.app.servertransaction.TransactionExecutor.executeLifecycleState(TransactionExecutor.java:142)
    at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:70)
    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1947)
    at android.os.Handler.dispatchMessage(Handler.java:106)
    at android.os.Looper.loop(Looper.java:214)
    at android.app.ActivityThread.main(ActivityThread.java:7032)
    at java.lang.reflect.Method.invoke(Native Method)
    at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:493)
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:964)

我启动服务如下：

@Override
protected void onStart() {
    if (BuildConfig.DEBUG_MODE) Log.d(TAG, "activity started");
    super.onStart();
    connectToBackend();
}

void connectToBackend() {
    Intent intent = new Intent(this, ConnectionService.class);
    intent.setAction("ui");
    startService(intent);
    getApplicationContext().bindService(intent, mConnection, Context.BIND_AUTO_CREATE);
}

我注意到只有当我在应用程序中锁定然后解锁手机时才会发生这种情况。我无法始终如一地重现它。

有人有同样的问题吗？

我使用的设备是三星 Galaxy S10e。

Answer 1

对于牛轧糖后设备，使用startForegroundService，对于奥利奥前设备，使用startService

if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
    startForegroundService(intent);
} else {
    startService(intent);
}