locationManager=(LocationManager) getSystemService(Context.LOCATION_SERVICE);
        //获取所有可用的位置服务器
        
        List<String> providerList = locationManager.getProviders(true);
        
        if(providerList.contains(LocationManager.GPS_PROVIDER)){
            provider=locationManager.GPS_PROVIDER;
        }else if(providerList.contains(LocationManager.NETWORK_PROVIDER)){
            provider=locationManager.NETWORK_PROVIDER;
    
        }else{
            //当没有可用的位置提供器时，弹出Toast提示用户
            Toast.makeText(this, "No location provider to use", Toast.LENGTH_SHORT).show();
            return;
        }