android判断服务是否是运行状态

/**
     * 判断服务是否处于运行状态.
     * @param servicename
     * @param context
     * @return
     */
    public static boolean isServiceRunning(String servicename,Context context){
        ActivityManager am = (ActivityManager) context.getSystemService(Context.ACTIVITY_SERVICE);
        List<RunningServiceInfo>  infos = am.getRunningServices(100);
        for(RunningServiceInfo info: infos){
            if(servicename.equals(info.service.getClassName())){
                return true;
            }
        }
        return false;
    }