kotlin简单小demo，请求，解析，gson的使用，volley的单例

-----------------------------------------------------------------------------------------------------------

mainactivity

class MainActivity : BaseActivity() {   internal val WHAT_MESSAGE = 0    var recyclerView : RecyclerView? = null    var adapter : MyAdapter? = null    override fun init() {        setContentView(R.layout.activity_main)        recyclerView = findViewById(R.id.recycler_view) as RecyclerView        recyclerView!!.layoutManager = LinearLayoutManager(this)        getData()    }    fun getData(){        var jsonRequest = JsonObjectRequest(Request.Method.GET                ,"http://www.tngou.net/api/food/list?id=1",null,Response.Listener<JSONObject> {             response: JSONObject ->            var gson = Gson()               var item : Foot = gson.fromJson(response.toString(),Foot::class.java)               var list : List<Tngou> = item.tngou               async {                  uiThread { adapter = MyAdapter(this@MainActivity,list)                  recyclerView!!.adapter = adapter                  }               }        },Response.ErrorListener { error ->            Log.d("---->error",error.toString())        })      SimpleRequest.getInstance(this).addToRequestQueue(jsonRequest)    }}-----------------------------------------------------------------------------adapter
class MyAdapter(var ctx:Context,var list: List<Tngou>) : Adapter<MyAdapter.MyViewHolder>() {    var inflater : LayoutInflater    init {        inflater = LayoutInflater.from(ctx)    }    override fun onBindViewHolder(holder: MyViewHolder, position: Int) {       holder.textTitle!!.text = list.get(position).description        holder.textContent!!.text = list.get(position).keywords        Glide.with(ctx).load("http://img1.imgtn.bdimg.com/it/u=489743113,36423855&fm=214&gp=0.jpg").into(holder.image)    }    override fun onCreateViewHolder(parent: ViewGroup?, viewType: Int): MyViewHolder {        var view : View = inflater.inflate(R.layout.item_view,null)         var holder : MyViewHolder = MyViewHolder(view)        return holder    }    override fun getItemCount(): Int {       return  list.size    }    class MyViewHolder(itemView : View) : RecyclerView.ViewHolder(itemView){      var textContent : TextView? = null      var textTitle : TextView? = null       var image : ImageView? =null        init {            textContent = itemView.findViewById(R.id.text_content) as TextView            image = itemView.findViewById(R.id.iv) as ImageView            textTitle = itemView.findViewById(R.id.description) as TextView        }    }}-----------------------------------------------------------------volley的单例
class  SimpleRequest private constructor(var ctx: Context){    private var requestQueue : RequestQueue? = null    init {        requestQueue = getRequestQueue()    }   private fun getRequestQueue() : RequestQueue? {       if (requestQueue==null){           requestQueue = Volley.newRequestQueue(ctx)       }       return requestQueue   }    //同步的代码块    companion object{        private var simpleRequest : SimpleRequest? = null        @Synchronized  fun getInstance(ctx : Context) : SimpleRequest {            if (simpleRequest == null){                simpleRequest = SimpleRequest(ctx)            }            return simpleRequest as SimpleRequest        }    }    //添加到请求队列    fun <T> addToRequestQueue(request : Request<T>) {        getRequestQueue()!!.add(request)    }}---------------------------------------------------------------------------两个dataclass
data class Foot(val status: Boolean,val total:Int,val tngou : List<Tngou>)
data class Tngou(val count : Int,var description : String,val disease : String,                 val fcount : Int,val food:String,val id:Int,val img : String = "",val keywords : String,                 val name:String,val rcount:Int,val summary:String,val symptom:String)
-----------------------------------------------------------------------------------
baseActivity
abstract class BaseActivity : Activity(){    override fun onCreate(savedInstanceState: Bundle?) {        super.onCreate(savedInstanceState)        init()    }    abstract fun init()}