判断程序是否在后台运行

public boolean isBackgroundRunning(){
 String processName = "com.enigma.yuemote";
 activityManager = (ActivityManager) getSystemService(ACTIVITY_SERVICE);
 KeyguardManager keyguardManager = (KeyguardManager) getSystemService(KEYGUARD_SERVICE);
 if (activityManager == null)
  return false;
  List<ActivityManager.RunningAppProcessInfo> processList = activityManager.getRunningAppProcesses();
  for (ActivityManager.RunningAppProcessInfo process : processList) {
  if (process.processName.startsWith(processName)) {
boolean isBackground = process.importance != ActivityManager.RunningAppProcessInfo.IMPORTANCE_FOREGROUND && process.importance != ActivityManager.RunningAppProcessInfo.IMPORTANCE_VISIBLE;
boolean isLockedState = keyguardManager.inKeyguardRestrictedInputMode();
 if (isBackground || isLockedState)
  return true;
 else
  return false;
 }
 }
 return false;
 }