android – 在QueryUtils中为每个片段更改值

概述如何从Fragment中更改QueryUtils文件中存在的json对象的索引值？ 这部分就在这里：JSONObject currentDay = dayArray.getJSONObject(0); 我想要为每个片段更改索引值,但无法绕过它.我尝试过意图并创建一个构造函数但失败了. 就像现在一样,应用程序正在“处理”所有显示星期一时间表的片段(JSONObject索引0). QueryUtils 如何从Fragment中更改queryUtils文件中存在的Json对象的索引值？

这部分就在这里：JSONObject currentDay = dayArray.getJsONObject(0);

我想要为每个片段更改索引值,但无法绕过它.我尝试过意图并创建一个构造函数但失败了.

就像现在一样,应用程序正在“处理”所有显示星期一时间表的片段(JsONObject索引0).

queryUtils.java

import androID.text.TextUtils;import androID.util.Log;import org.Json.JsONArray;import org.Json.JsONException;import org.Json.JsONObject;import java.io.BufferedReader;import java.io.IOException;import java.io.inputStream;import java.io.inputStreamReader;import java.net.httpURLConnection;import java.net.MalformedURLException;import java.net.URL;import java.nio.charset.Charset;import java.util.Array@R_502_6818@;import java.util.@R_502_6818@;public final class queryUtils {    private static final String LOG_TAG = queryUtils.class.getSimplename();    //makehttpRequest constants    private static final int READ_TIMEOUT = 10000 /* milliseconds */;    private static final int CONNECT_TIMEOUT = 15000 /* milliseconds */;    private static final int RESPONSE_CODE = 200 /*everything is OK*/;    public queryUtils() {    }    public static @R_502_6818@<Day> fetchDayData(String requestUrl) {        URL url = createUrl(requestUrl);        String JsonResponse = null;        try {            JsonResponse = makehttpRequest(url);        } catch (IOException e) {            Log.e(LOG_TAG,"Problem making the http request.",e);        }        @R_502_6818@<Day> days = extractFeatureFromJson(JsonResponse);        return days;    }    private static URL createUrl(String stringUrl) {        URL url = null;        try {            url = new URL(stringUrl);        } catch (MalformedURLException e) {            Log.e(LOG_TAG,"Problem building the URL ",e);        }        return url;    }    private static String makehttpRequest(URL url) throws IOException {        String JsonResponse = "";        if (url == null) {            return JsonResponse;        }        httpURLConnection urlConnection = null;        inputStream inputStream = null;        try {            urlConnection = (httpURLConnection) url.openConnection();            urlConnection.setReadTimeout(READ_TIMEOUT);            urlConnection.setConnectTimeout(CONNECT_TIMEOUT);            urlConnection.setRequestMethod("GET");            urlConnection.connect();            if (urlConnection.getResponseCode() == RESPONSE_CODE) {                inputStream = urlConnection.getinputStream();                JsonResponse = readFromStream(inputStream);            } else {                Log.e(LOG_TAG,"Error response code: " + urlConnection.getResponseCode());            }        } catch (IOException e) {            Log.e(LOG_TAG,"Problem retrIEving Berceni JsON results.",e);        } finally {            if (urlConnection != null) {                urlConnection.disconnect();            }            if (inputStream != null) {                inputStream.close();            }        }        return JsonResponse;    }    private static String readFromStream(inputStream inputStream) throws IOException {        StringBuilder output = new StringBuilder();        if (inputStream != null) {            inputStreamReader inputStreamReader = new inputStreamReader(inputStream,Charset.forname("UTF-8"));            BufferedReader reader = new BufferedReader(inputStreamReader);            String line = reader.readline();            while (line != null) {                output.append(line);                line = reader.readline();            }        }        return output.toString();    }    private static @R_502_6818@<Day> extractFeatureFromJson(String dayJsON) {        if (TextUtils.isEmpty(dayJsON)) {            return null;        }        @R_502_6818@<Day> days = new Array@R_502_6818@<>();        //Try to parse        try {            JsONObject baseJsonResponse = new JsONObject(dayJsON);            JsONArray dayArray = baseJsonResponse.getJsONObject("schedule").getJsONArray("day");            JsONObject currentDay = dayArray.getJsONObject(0);            JsONArray getClasses = currentDay.getJsONArray("classes");                for (int j = 0; j < getClasses.length(); j++) {                    JsONObject currentClass = getClasses.getJsONObject(j);                     String retrIEveCourseTitle = currentClass.getString("class");                     String retrIEveCourseTime = currentClass.getString("time");                     String retrIEveCourseTrainer = currentClass.getString("trainer");                     String retrIEveCourseCancelState = currentClass.getString("canceled");                     Day day = new Day(retrIEveCourseTitle,retrIEveCourseTime,retrIEveCourseTrainer,retrIEveCourseCancelState);                     days.add(day);                }        } catch (JsONException e) {            // If an error is thrown when executing any of the above statements in the "try" block,// catch the exception here,so the app doesn't crash. Print a log message            // with the message from the exception.            Log.e("queryUtils","Problem parsing JsON results",e);        }        return days;    }}

还有我的FragmentAdapter.java

import androID.content.Context;import androID.support.v4.app.Fragment;import androID.support.v4.app.FragmentManager;import androID.support.v4.app.FragmentPagerAdapter;public class FragmentAdapter extends FragmentPagerAdapter {    private Context mContext;    public FragmentAdapter(Context context,FragmentManager fm) {        super(fm);        mContext = context;    }    @OverrIDe    public Fragment getItem(int position) {        if (position == 0) {            return new MondayFragment();        } else if (position == 1) {            return new ThursdayFragment();        } else if (position == 2) {            return new WednesdayFragment();        } else if (position == 3) {            return new ThursdayFragment();        } else if (position == 4) {            return new FrIDayFragment();        } else if (position == 5) {            return new SaturdayFragment();        } else {            return new SundayFragment();        }    }    /**     * Return the total number of pages.     */    @OverrIDe    public int getCount() {        return 7;    }    @OverrIDe    public CharSequence getPageTitle(int position) {        if (position == 0) {            return mContext.getString(R.string.monday);        } else if (position == 1) {            return mContext.getString(R.string.tuesday);        } else if (position == 2) {            return mContext.getString(R.string.wednesday);        } else if (position == 3) {            return mContext.getString(R.string.thursday);        } else if (position == 4) {            return mContext.getString(R.string.frIDay);        } else if (position == 5) {            return mContext.getString(R.string.saturday);        }   else {            return mContext.getString(R.string.sunday);        }    }}

JsON示例响应

{     "schedule":{      "day":[         {              "ID":"Monday","classes":[                {                    "class" : "Class","time" : "00:00","trainer" : "Teacher","canceled" : ""                },{                    "class" : "Class","canceled" : ""                }            ]         },{              "ID":"Tuesday",{              "ID":"Wednesday",{              "ID":"Thursday",{              "ID":"FrIDay",{              "ID":"Saturday",{              "ID":"Sunday","classes":[]         }      ]   }}

解决方法 查看您的POJO,这并不明确等于您的JsON.

一天应宣布为：

class Day {    String ID;    @R_502_6818@<ClassDetail> classes;}class ClassDetail {    //all the details}

我认为你错过了接受你的功能,跟随签名不是太明确.

@R_502_6818@<Day> extractFeatureFromJson(String dayJsON)

为了使其更具可读性,我建议将其更改为：
(您可以使用Hashmap as recommended for @ρяσѕρєя)：

HashMap<String,ClassDetail> parseScheduleJson(String scheduleJsON)

并将每个ClassDetail添加到结果中

@Nullableprivate static Map<String,@R_502_6818@<ClassDetail>> parseScheduleJson(String scheduleJsON) {    if (TextUtils.isEmpty(scheduleJsON)) {        return null;    }    HashMap<String,@R_502_6818@<ClassDetail>> result = new HashMap<>();    try {        JsONObject baseJsonResponse = new JsONObject(scheduleJsON);        JsONArray dayArray = baseJsonResponse.getJsONObject("schedule").getJsONArray("day");        for (int i = 0; i < dayArray.length(); i++) {            Array@R_502_6818@<ClassDetail> classes = new Array@R_502_6818@<>();            JsONObject currentDay = dayArray.getJsONObject(i);            for (int j = 0; j < currentDay.getJsONArray("classes").length(); j++) {                JsONObject currentClass = currentDay.getJsONArray("classes").getJsONObject(j);                String retrIEveCourseTitle = currentClass.getString("class");                String retrIEveCourseTime = currentClass.getString("time");                String retrIEveCourseTrainer = currentClass.getString("trainer");                String retrIEveCourseCancelState = currentClass.getString("canceled");                classes.add(new ClassDetail(retrIEveCourseTitle,retrIEveCourseCancelState));            }            result.put(currentDay.getString("ID"),classes);        }    } catch (JsONException e) {        // If an error is thrown when executing any of the above statements in the "try" block,so the app doesn't crash. Print a log message        // with the message from the exception.        Log.e("queryUtils",e);        return null;    }    return result;}

在此之后,您可以使用以下方式访问当天的课程列表：

mymap.get("Monday");mymap.get("Tuesday");...mymap.get("Sunday");

编辑：

恕我直言,你必须在你的活动中调用你的日常活动,并将地图结果注入你的FragmentPagerAdapter：

public FragmentAdapter(Context context,FragmentManager fm,Map<String,@R_502_6818@<ClassDetail> schedule) {    super(fm);    mContext = context;    mSchedule = schedule;}@OverrIDepublic Fragment getItem(int position) {    if (position == 0) {        return MondayFragment.newInstance(mSchedule.get("Monday"));    //...    //same for all conditions    //...    } else {        return SundayFragment.newInstance(mSchedule.get("Sunday"));    }}

之后使用newIntance pattern时,您可以将片段声明为：

private @R_502_6818@<ClassDetail> mClasses;public static MondayClassDetailFragment newInstance(Array@R_502_6818@<ClassDetail> classes){    MondayClassDetailFragment myFragment = new MondayClassDetailFragment();    Bundle args = new Bundle();    args.putParcelableArray@R_502_6818@("classes",classes);    myFragment.setArguments(args);    return myFragment;}@OverrIDepublic voID onCreate(@Nullable Bundle savedInstanceState) {    super.onCreate(savedInstanceState);    mClasses = getArguments().getParcelableArray@R_502_6818@("classes");}

PS：在这些日子手动发出http请求和解析Json是浪费精力.我建议你去看看图书馆这样做,尤其是retrofit,它被广泛使用并且有很好的文档记录.

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