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如何使用Android调用Web服务

web-services rest android

user9569492 · 技术社区 · 8 年前

我是Android应用程序开发的新手。我正在开发一个购物车应用程序。我正在尝试使用android调用GET方法中的web服务。但我该怎么做呢?我试过的就在这里。但这给了我一个错误 PostResponseAsyncTask: 405 Method not allowed .如何修复?有人能帮我吗?提前谢谢。

MainFragment类

public class MainFragment extends Fragment implements AsyncResponse, AdapterView.OnItemClickListener{
    public static final String PREFS = "prefFile";
    final String LOG = "MainFragment";

    final static String url = "http://10.0.3.2:8080/WebService/rest/get/products";

    private ArrayList<Products> productList;
    private ListView lv;
    FunDapter<Products> adapter;

    View view;


    public MainFragment() {

    }


    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {

        view = inflater.inflate(R.layout.fragment_main, container, false);

        ImageLoader.getInstance().init(UILConfig.config(MainFragment.this.getActivity()));

        PostResponseAsyncTask taskRead = new PostResponseAsyncTask(MainFragment.this.getActivity(), this);
        taskRead.execute(url);


        return view;
    }

    @Override
    public void processFinish(String s) {

        productList = new JsonConverter<Products>().toArrayList(s, Products.class);

        BindDictionary dic = new BindDictionary();

        dic.addStringField(R.id.tvName, new StringExtractor<Products>() {
            @Override
            public String getStringValue(Products item, int position) {
                return item.name;
            }
        });

        dic.addStringField(R.id.tvDesc, new StringExtractor<Products>() {
            @Override
            public String getStringValue(Products item, int position) {
                return item.description;
            }
        }).visibilityIfNull(View.GONE);

        dic.addStringField(R.id.tvPrice, new StringExtractor<Products>() {
            @Override
            public String getStringValue(Products item, int position) {
                return ""+item.price;
            }
        });

        dic.addDynamicImageField(R.id.ivImage, new StringExtractor<Products>() {
            @Override
            public String getStringValue(Products item, int position) {
                return item.pic;
            }
        }, new DynamicImageLoader() {
            @Override
            public void loadImage(String url, ImageView img) {
                //Set image
                ImageLoader.getInstance().displayImage(url, img);
            }
        });

        dic.addBaseField(R.id.btnCart).onClick(new ItemClickListener() {
        });

        adapter = new FunDapter<>(MainFragment.this.getActivity(), productList, R.layout.product_row, dic);
        lv = (ListView)view.findViewById(R.id.lvProduct);
        lv.setAdapter(adapter);

        lv.setOnItemClickListener(this);

    }

    @Override
    public void onItemClick(AdapterView<?> parent, View view, int position, long id) {

    }
}

4 回复 | 直到 8 年前

Tomin B Azhakathu 8 年前

尝试使用一些库,如Reformation、Volley、Loopj等来处理异步GET或POST HTTP请求。

要从url或文件路径实现动态图像,请使用Piccasso或Glide库。

下面是关于这些库的一些示例和文档

Loopj

Loopj official Documentation and Example

改装

截击

动态图像处理

毕加索

Android Picasso Library

滑行

Glide Library for Android

希望这些可以帮助你

改装示例

建筑gradle(应用程序)

        implementation 'com.google.code.gson:gson:2.6.2'
        implementation 'com.squareup.retrofit2:retrofit:2.0.2'
        implementation 'com.squareup.retrofit2:converter-gson:2.0.2'

主要片段

public class MainFragment extends Fragment {

    public static final String PREFS = "prefFile";
    final String LOG = "MainFragment";

    private ArrayList<Product> productList;
    private ListView lv;
    FunDapter adapter;
    private ApiInterface apiInterface;

    View view;


    public MainFragment() {
        // Required empty public constructor
    }


    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {
        // Inflate the layout for this fragment
        return inflater.inflate(R.layout.fragment_main, container, false);
    }

    @Override
    public void onViewCreated(@NonNull View view, @Nullable Bundle savedInstanceState) {
        super.onViewCreated(view, savedInstanceState);


        lv = (ListView) view.findViewById(R.id.lvProduct);
        apiInterface = ApiClient.getRetrofitApiClient().create(ApiInterface.class);

        productList  = new ArrayList<Product>();

        adapter= new FunDapter (getContext(), 0, productList);
        lv.setAdapter(adapter);

        getProduct();


    }

    private void getProduct() {

        Call<List<Product>> call = apiInterface.getProducts();
        call.enqueue(new Callback<List<Product>>() {
            @Override
            public void onResponse(Call<List<Product>> call, Response<List<Product>> response) {

                List<Product> products= response.body();
                Log.d("TEST", "onResponse: "+response.body().size());
                if(products.size()>0){
                    productList.addAll(products);
                }

                adapter.notifyDataSetChanged();
            }

            @Override
            public void onFailure(Call<List<Product>> call, Throwable t) {

            }
        });

    }
}

ApiClient公司

import retrofit2.Retrofit;
import retrofit2.converter.gson.GsonConverterFactory;

/**
 * Created by android on 3/10/17.
 */
class ApiClient {

        public static final String BASE_URL = "http://10.0.2.2:8080/WebService/rest/";

        public static Retrofit retrofit = null;

        public static Retrofit getRetrofitApiClient() {
            if (retrofit == null) {
                retrofit = new Retrofit.Builder().baseUrl(BASE_URL).addConverterFactory(GsonConverterFactory.create()).build();
            }

            return retrofit;
        }
    }

API接口

import java.util.List;

import retrofit2.Call;
import retrofit2.http.Body;
import retrofit2.http.GET;
import retrofit2.http.POST;
import retrofit2.http.Query;


public interface ApiInterface {

    @GET("get/products")
    Call<List<Product>> getProducts();

}

产品

import com.google.gson.annotations.Expose;
import com.google.gson.annotations.SerializedName;

class Product {

    @SerializedName("name")
    @Expose
    private String name;
    @SerializedName("ram")
    @Expose
    private String ram;
    @SerializedName("price")
    @Expose
    private String price;
    @SerializedName("pic")
    @Expose
    private String pic;

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public String getRam() {
        return ram;
    }

    public void setRam(String ram) {
        this.ram = ram;
    }

    public String getPrice() {
        return price;
    }

    public void setPrice(String price) {
        this.price = price;
    }

    public String getPic() {
        return pic;
    }

    public void setPic(String pic) {
        this.pic = pic;
    }

}

FunDapter公司

class FunDapter extends ArrayAdapter<Product> {

    private Context context;
    private ArrayList<Product> objects;
    private static LayoutInflater inflater = null;

    public FunDapter(@NonNull Context context, int resource, @NonNull ArrayList<Product> objects) {
        super(context, resource, objects);
        try {
            this.context = context;
            this.objects = objects;

            inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);

        } catch (Exception e) {

        }
    }
    public int getCount() {
        return objects.size();
    }

    public Product getItem(Product position) {
        return position;
    }

    public long getItemId(int position) {
        return position;
    }

    public static class ViewHolder {
        public TextView display_name;
        public TextView display_number;
        public ImageView image;

    }

    public View getView(int position, View convertView, ViewGroup parent) {
        View vi = convertView;
        final ViewHolder holder;
        try {
            if (convertView == null) {
                vi = inflater.inflate(R.layout.singlerow_mylistview, null);
                holder = new ViewHolder();

                holder.display_name = (TextView) vi.findViewById(R.id.title_listview);
                holder.display_number = (TextView) vi.findViewById(R.id.subtitle_listview);
                holder.image = (ImageView) vi.findViewById(R.id.icon_listview);



                vi.setTag(holder);
            } else {
                holder = (ViewHolder) vi.getTag();
            }



            holder.display_name.setText(objects.get(position).getName());
            holder.display_number.setText(objects.get(position).getPrice());

            Picasso.with(context)
                    .load(objects.get(position).getPic())
                    .resize(50, 50)
                    .centerCrop()
                    .into(holder.image);


        } catch (Exception e) {


        }
        return vi;
    }
}

别忘了添加 <uses-permission android:name="android.permission.INTERNET" /> 在舱单中

noman404 8 年前

您正在执行POST请求 PostResponseAsyncTask 这就是为什么你 405 Method not allowed 。如果该端点接受GET,则执行GET请求。你应该使用更好的截击或改装网络通信图书馆。

Navneet Krishna 8 年前

尝试使用改装,首先添加以下依赖项

compile 'com.squareup.retrofit2:retrofit:2.3.0'

compile 'com.squareup.retrofit2:converter-gson:2.3.0'

首先,尝试找出您从后端得到的json响应的类型,它可以是数组响应/对象响应。

Json数组响应的形式如下 [{"field1":"value1",..},{"field2":"value2",..}..] 鉴于对象回复的形式如下 {"field1":"value1",..}

您可以检查 this tutorial 了解如何解析json响应

如果检查后端并找出响应,则可以使用相同的 http://www.jsonschema2pojo.org/

案例1:假设您有 json object 回答 ( {“field1”:“value1”,…} )

首先使用您的响应创建一个模型类 jsonschema2pojo 如上所述,然后像下面这样调用它(假设 YourObjectModel 是您的模型类)

Retrofit retrofit = new Retrofit.Builder()
            .baseUrl("http://10.0.3.2:8080/WebService/")
            .addConverterFactory(GsonConverterFactory.create())
            .build();

    SampleInterface request = retrofit.create(SampleInterface.class);
    Call<YourObjectModel> call1=request.getResponse();
    call1.enqueue(new Callback<YourObjectModel>() {
        @Override
        public void onResponse(Call<YourObjectModel> call, Response<YourObjectModel> response) {
            Toast.makeText(MainActivity.this,response.body().toString(),Toast.LENGTH_SHORT).show();
        }

        @Override
        public void onFailure(Call<YourObjectModel> call, Throwable t) {
            Toast.makeText(MainActivity.this,t.toString(),Toast.LENGTH_SHORT).show();
        }

    });

SampleInterface。JAVA

public interface SampleInterface {
@GET("rest/get/products")
Call<YourObjectModel> getResponse();
}

案例2:假设您有 json array 回答 ( [{“field1”:“value1”,…},{“field2”:“value2”,…}….] )

首先像上面的例子一样创建一个模型类,因为它是一个数组响应,所以您可能需要将响应作为列表来获取,所以更改所有 call 方法来自 Call<YourObjectModel> 到 Call<List<YourArrayModel>>

哪里 YourArrayModel 是json数组响应的模型类

yathavan 8 年前

试试这个例子,这很简单,这个例子一定对你有帮助。