联网请求数据：Android篇

这篇文章主要回顾之前的MYangtzeu App教程的联网请求方法和json解析套路，主要目的是实现左侧菜单数据的联网获取。

1、先上请求地址实体类Constants.java

package com.vitoyan.myangtzeu.utils;

/**
 * 作者：Vito-Yan
 * 作用：常量类，配置联网请求地址
 */
public class Constants {

    /**
     * 联网请求的ip和端口
     */
    public static final String BASE_URL = "http://10.155.106.108:9090/web_home";
//    public static final String BASE_URL = "http://192.168.191.1:8080/web_home";

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

    /**
     * 新闻中心的网络地址
     */
    public static final String HOME_PAGER_URL = BASE_URL+"/static/api/news/categories.json";
}

2、解析Json后的实体类HomePageBean.java

package com.vitoyan.myangtzeu.pojo;

import java.util.List;

/**
 * 作者：Vito-Yan
 * 作用：新闻中心解析后对应的数据
 */
public class HomePagerBean {

    private List<DetailPagerData> data;
    private List extend;
    private int retcode;

    public List<DetailPagerData> getData() {
        return data;
    }

    public void setData(List<DetailPagerData> data) {
        this.data = data;
    }

    public List getExtend() {
        return extend;
    }

    public void setExtend(List extend) {
        this.extend = extend;
    }

    public int getRetcode() {
        return retcode;
    }

    public void setRetcode(int retcode) {
        this.retcode = retcode;
    }

    @Override
    public String toString() {
        return "NewsCenterPagerBean2{" +
                "data=" + data +
                ", extend=" + extend +
                ", retcode=" + retcode +
                '}';
    }

    public static class DetailPagerData{
        private int id;
        private String title;
        private int type;
        private String url;
        private String url1;
        private String dayurl;
        private String excurl;
        private String weekurl;
        private List<ChildrenData> children;

        public int getId() {
            return id;
        }

        public void setId(int id) {
            this.id = id;
        }

        public String getTitle() {
            return title;
        }

        public void setTitle(String title) {
            this.title = title;
        }

        public int getType() {
            return type;
        }

        public void setType(int type) {
            this.type = type;
        }

        public String getUrl() {
            return url;
        }

        public void setUrl(String url) {
            this.url = url;
        }

        public String getUrl1() {
            return url1;
        }

        public void setUrl1(String url1) {
            this.url1 = url1;
        }

        public String getDayurl() {
            return dayurl;
        }

        public void setDayurl(String dayurl) {
            this.dayurl = dayurl;
        }

        public String getExcurl() {
            return excurl;
        }

        public void setExcurl(String excurl) {
            this.excurl = excurl;
        }

        public String getWeekurl() {
            return weekurl;
        }

        public void setWeekurl(String weekurl) {
            this.weekurl = weekurl;
        }

        public List<ChildrenData> getChildren() {
            return children;
        }

        public void setChildren(List<ChildrenData> children) {
            this.children = children;
        }

        @Override
        public String toString() {
            return "DetailPagerData{" +
                    "id=" + id +
                    ", title='" + title + '\'' +
                    ", type=" + type +
                    ", url='" + url + '\'' +
                    ", url1='" + url1 + '\'' +
                    ", dayurl='" + dayurl + '\'' +
                    ", excurl='" + excurl + '\'' +
                    ", weekurl='" + weekurl + '\'' +
                    ", children=" + children +
                    '}';
        }

        public static class ChildrenData{
            private int id;
            private String title;
            private int type;
            private String url;

            public int getId() {
                return id;
            }

            public void setId(int id) {
                this.id = id;
            }

            public String getTitle() {
                return title;
            }

            public void setTitle(String title) {
                this.title = title;
            }

            public int getType() {
                return type;
            }

            public void setType(int type) {
                this.type = type;
            }

            public String getUrl() {
                return url;
            }

            public void setUrl(String url) {
                this.url = url;
            }

            @Override
            public String toString() {
                return "ChildrenData{" +
                        "id=" + id +
                        ", title='" + title + '\'' +
                        ", type=" + type +
                        ", url='" + url + '\'' +
                        '}';
            }
        }
    }
}

3、使用xUtils3联网请求数据，使用前自行下载modules

/**
     * 使用xUtils3联网请求数据
     */
    private void getDataFromNet() {

        RequestParams params = new RequestParams(Constants.HOME_PAGER_URL);
        x.http().get(params, new Callback.CommonCallback<String>() {
            @Override
            public void onSuccess(String result) {
                long endTime = SystemClock.uptimeMillis();
                long passTime = endTime - startTime;

                LogUtil.e("xUtils3--passTime==" + passTime);

                LogUtil.e("使用xUtils3联网请求成功==" + result);

                //缓存数据
                CacheUtils.putString(context,Constants.HOME_PAGER_URL,result);

                //解析json数据和显示数据
                processData(result);

                //设置适配器

            }

            @Override
            public void onError(Throwable ex, boolean isOnCallback) {
                LogUtil.e("使用xUtils3联网请求失败==" + ex.getMessage());
            }

            @Override
            public void onCancelled(CancelledException cex) {
                LogUtil.e("使用xUtils3-onCancelled==" + cex.getMessage());
            }

            @Override
            public void onFinished() {
                LogUtil.e("使用xUtils3-onFinished");
            }
        });

    }

4、解析Json，这里使用Gson解析

/**
     * 解析json数据：1,使用系统的API解析json；2,使用第三方框架解析json数据，例如Gson,fastjson
     *
     * @param json
     * @return
     */
    private HomePagerBean parsedJson(String json) {
        //        Gson gson = new Gson();
        //        HomePagerBean bean = gson.fromJson(json,HomePagerBean.class);
        return new Gson().fromJson(json, HomePagerBean.class);
    }

5、解析Json数据和显示数据

/**
     * 解析json数据和显示数据
     *
     * @param json
     */
    private void processData(String json) {

        HomePagerBean bean = parsedJson(json);
//        HomePagerBean2 bean = parsedJson2(json);
//        String title = bean.getData().get(0).getChildren().get(1).getTitle();

//        LogUtil.e("使用Gson解析json数据成功-title==" + title);
        String title2 = bean.getData().get(0).getChildren().get(1).getTitle();
        LogUtil.e("使用Gson解析json数据成功HomePagerBean2-title2-------------------------==" + title2);
        //给左侧菜单传递数据
        data = bean.getData();

        MainActivity mainActivity = (MainActivity) context;
        //得到左侧菜单
        LeftmenuFragment leftmenuFragment = mainActivity.getLeftmenuFragment();

        //添加详情页面
        detaiBasePagers = new ArrayList<>();
        detaiBasePagers.add(new NewsMenuDetailPager(context,data.get(0)));//新闻详情页面
        detaiBasePagers.add(new News1MenuDetailPager(context));//新闻1详情页面
        detaiBasePagers.add(new News2MenuDetailPager(context));//新闻2详情页面
        detaiBasePagers.add(new News3MenuDetailPager(context));//新闻3详情页面
        detaiBasePagers.add(new News4MenuDetailPager(context));//新闻4详情页面

        //把数据传递给左侧菜单
        leftmenuFragment.setData(data);

    }

6、在LeftmenuFragment中接受数据

/**
     * 接收数据
     * @param data
     */
    public void setData(List<HomePagerBean.DetailPagerData> data) {
        this.data = data;
        for(int i=0;i<data.size();i++){
            LogUtil.e("title=="+data.get(i).getTitle());
        }

        //设置适配器
        adapter   = new LeftmenuFragmentAdapter();
        listView.setAdapter(adapter);

        //设置默认页面
        swichPager(prePosition);

    }