Android 8.0 启动Service适配(Not allowed to start service Intent)
问题现象：
App出现异常： java.lang.IllegalStateException: Not allowed to start service Intent xxxx app is in background uid UidRecord
App直接崩溃。
问题原因：
App targetSdkVersion>= 26的情况下，用户允许App开机自启动，App被杀死或者系统重启后，系统直接将App后台启动起来，App在后台启动的过程中有使用startService()方法。
Google在Android 8.0之后对于处于后台的App启动Service进行了严格的限制，不再允许后台App启动后台Service，如果使用会直接抛出异常。
问题调研：
- 微信：反编译App后，没有找到对应Service的代码，怀疑可能是热加载的
- QQ：目前targetSdkVersion = 23，不存在此问题
- 小天才：使用startForegroundService方法，Notification设置channel为null，状态栏不显示通知
- 360儿童卫士：使用startForegroundService方法，Notification正常设置，状态栏显示通知
解决方法：
使用startForegroundService，此方法会在状态栏显示通知
// 启动服务的地方
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
context.startForegroundService(new Intent(context, MyService.class));
} else {
context.startService(new Intent(context, MyService.class));
}// 在MyService中
@Override
public void onCreate() {
super.onCreate();
if (android.os.Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.O) {
NotificationManager notificationManager = (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);
NotificationChannel channel = null;
channel = new NotificationChannel(CHANNEL_ID_STRING, getString(R.string.app_name), NotificationManager.IMPORTANCE_HIGH);
notificationManager.createNotificationChannel(channel);
Notification notification = new Notification.Builder(getApplicationContext(), CHANNEL_ID_STRING).build();
startForeground(1, notification);
}
}
去除状态栏方法
stopForeground()
//在 startForeground(1, notification);后添加如下代码，取消前台服务
myHandler.postDelayed(new Runnable() {
@Override
public void run() {
stopForeground(true);
}
}, 1000);channel 设置为null，此方法只适用于targetSdkVersion = 26的情况
Notification.Builder builder = new Notification.Builder(this, null)
.setContentTitle(getString(R.string.app_name))
.setContentText("")
.setAutoCancel(true);
Notification notification = builder.build();
startForeground(1, notification);对于去除通知的第2种方法，源码查看：
final class ServiceRecord extends Binder implements ComponentName.WithComponentName {
public void postNotification() {
if (foregroundId != 0 && foregroundNoti != null) {
...
ams.mHandler.post(new Runnable() {
public void run() {
NotificationManagerInternal nm = LocalServices.getService(NotificationManagerInternal.class);
if (nm == null) {
return;
}
Notification localForegroundNoti = _foregroundNoti;
try {
if (localForegroundNoti.getSmallIcon() == null) {
...//没有smallIcon进行处理
}
if (nm.getNotificationChannel(localPackageName, appUid, localForegroundNoti.getChannelId()) == null) {
int targetSdkVersion = Build.VERSION_CODES.O_MR1;
try {
final ApplicationInfo applicationInfo = ams.mContext.getPackageManager().getApplicationInfoAsUser(appInfo.packageName, 0, userId);
targetSdkVersion = applicationInfo.targetSdkVersion;
} catch (PackageManager.NameNotFoundException e) {
}
if (targetSdkVersion >= Build.VERSION_CODES.O_MR1) {
throw new RuntimeException("invalid channel for service notification: " + foregroundNoti);
}
}
nm.enqueueNotification(localPackageName, localPackageName, appUid, appPid, null, localForegroundId, localForegroundNoti, userId);
foregroundNoti = localForegroundNoti; // save it for amending next time
} catch (RuntimeException e) {
Slog.w(TAG, "Error showing notification for service", e);
// If it gave us a garbage notification, it doesn't
// get to be foreground.
ams.setServiceForeground(name, ServiceRecord.this, 0, null, 0);
ams.crashApplication(appUid, appPid, localPackageName, -1, "Bad notification for startForeground: " + e);
}
}
});
}
}
}从源码中可以看出，在发送通知检查时，如果targetSdkVersion >= Build.VERSION_CODES.O_MR1即targetSdkVersion >= 27时，如果设置channel为null才会抛出RuntimeException，crash当前App。
对于targetSdkVersion = 26的app会捕获异常，正常将notification加入队列，但此notification并不会进行显示。