/** 判斷程序是否在后臺運行 */
public static boolean isRunBackground(Context context) {
  ActivityManager activityManager = (ActivityManager) context
      .getSystemService(Context.ACTIVITY_SERVICE);
  List<RunningAppProcessInfo> appProcesses = activityManager
      .getRunningAppProcesses();
  for (RunningAppProcessInfo appProcess : appProcesses) {
    if (appProcess.processName.equals(context.getPackageName())) {
      if (appProcess.importance == RunningAppProcessInfo.IMPORTANCE_BACKGROUND) {
        // 表明程序在后臺運行
        return true;
      } else {
        return false;
      }
    }
  }
  return false;
}
/** 判斷程序是否在前臺運行（當前運行的程序） */
public boolean isRunForeground() {
  ActivityManager activityManager = (ActivityManager) getApplicationContext()
      .getSystemService(Context.ACTIVITY_SERVICE);
  String packageName = getApplicationContext().getPackageName();
  List<RunningAppProcessInfo> appProcesses = activityManager
      .getRunningAppProcesses();
  if (appProcesses == null)
    return false;
  for (RunningAppProcessInfo appProcess : appProcesses) {
    if (appProcess.processName.equals(packageName)
        && appProcess.importance == RunningAppProcessInfo.IMPORTANCE_FOREGROUND) {
      return true;// 程序運行在前臺
    }
  }
  return false;
}