Question

正如标题所说，我希望能够将ACTION_DOWN上给出的坐标传递给onPostExecute内部类的AsyncTask方法。过去两天我一直试图这样做但没有成功。我该怎么做？任何帮助表示赞赏：）

这是我的代码：

package io.music.ui.settings;

import android.app.ProgressDialog;
import android.content.Intent;
import android.net.Uri;
import android.os.AsyncTask;
import android.os.Bundle;
import android.os.Handler;
import android.os.SystemClock;
import android.support.annotation.Nullable;

import android.support.v7.widget.LinearLayoutManager;
import android.support.v7.widget.RecyclerView;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;


import io.music.R;
import io.music.ui.base.BaseFragment;
import io.music.ui.main.MainActivity;

import android.view.MotionEvent;
import android.widget.ProgressBar;
import android.widget.TextView;
import android.widget.Toast;

import com.android.volley.RequestQueue;
import com.android.volley.toolbox.JsonArrayRequest;

import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;

import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.OutputStreamWriter;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;
import java.util.ArrayList;
import java.util.List;

import static android.R.attr.x;


public class SettingsFragment extends BaseFragment {

    public static final int CONNECTION_TIMEOUT = 10000;
    public static final int READ_TIMEOUT = 15000;
    private RecyclerView mRVFishPrice;
    private AdapterFish mAdapter;
    public float x = 0.95f;
    //String xx = String.format("%.2f", x);
    public float y = 0;
    float x1, x2, y1, y2;

    List<DataFish> data=new ArrayList<>();
    @Nullable
    @Override
    public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {

        final View view = inflater.inflate(R.layout.fragment_settings, container, false);

        view.setOnTouchListener(new View.OnTouchListener() {
            public boolean onTouch(View v, MotionEvent event) {

                int action = event.getAction();
                if (action == MotionEvent.ACTION_DOWN) {

                    x = 2f * (event.getX() / v.getWidth()) - 1f;
                    y = -2f * (event.getY() / v.getHeight()) + 1f;

                    //x1 = x - 0.1f;
                    //x2 = x + 0.1f;
                    //y1 = y - 0.1f;
                    //y2 = y + 0.1f;
                    TextView textView = (TextView) getView().findViewById(R.id.textView2);
                    textView.setText(String.format("%.2f", x));
                    TextView textView2 = (TextView) getView().findViewById(R.id.textView3);
                    textView2.setText(String.format("%.2f", y));
                }

                mRVFishPrice = (RecyclerView) view.findViewById(R.id.fishPriceList);
                mAdapter = new AdapterFish(getActivity(), data);
                mRVFishPrice.setAdapter(mAdapter);
                mRVFishPrice.setLayoutManager(new LinearLayoutManager(getActivity()));

                return false;
            }

        });


        new AsyncFetch().execute();

        return view;
    }




    private class AsyncFetch extends AsyncTask<String, String, String> {
        ProgressDialog pdLoading = new ProgressDialog(getActivity());
        HttpURLConnection conn;
        URL url = null;

        @Override
        protected void onPreExecute() {
            super.onPreExecute();

            //this method will be running on UI thread
            pdLoading.setMessage("\tLoading...");
            pdLoading.setCancelable(false);
            pdLoading.show();

        }

        @Override
        protected String doInBackground(String... params) {
            try {

                // Enter URL address where your json file resides
                // Even you can make call to php file which returns json data
                url = new URL("http://example.com/Subjects2.php");

            } catch (MalformedURLException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
                return e.toString();
            }
            try {

                // Setup HttpURLConnection class to send and receive data from php and mysql
                conn = (HttpURLConnection) url.openConnection();
                conn.setReadTimeout(READ_TIMEOUT);
                conn.setConnectTimeout(CONNECTION_TIMEOUT);
                conn.setRequestMethod("POST");

                // setDoOutput to true as we recieve data from json file

                conn.setDoOutput(true);


            } catch (IOException e1) {
                // TODO Auto-generated catch block
                e1.printStackTrace();
                return e1.toString();
            }

            try {

                int response_code = conn.getResponseCode();

                // Check if successful connection made
                if (response_code == HttpURLConnection.HTTP_OK) {

                    // Read data sent from server
                    InputStream input = conn.getInputStream();
                    BufferedReader reader = new BufferedReader(new InputStreamReader(input));
                    StringBuilder result = new StringBuilder();
                    String line;

                    while ((line = reader.readLine()) != null) {
                        result.append(line);
                    }

                    // Pass data to onPostExecute method
                    return (result.toString());

                } else {

                    return ("unsuccessful");
                }

            } catch (IOException e) {
                e.printStackTrace();
                return e.toString();
            } finally {
                conn.disconnect();
            }


        }


        @Override
        public void onPostExecute(String result) {

            //this method will be running on UI thread


            pdLoading.dismiss();


            pdLoading.dismiss();
            try {

                JSONArray jArray = new JSONArray(result);

                // Extract data from json and store into ArrayList as class objects
                for(int i=0;i<jArray.length();i++){

                    JSONObject json_data = jArray.getJSONObject(i);

                    String xx= String.format("%.2f", x);
                    if(json_data.getString("X").equals(xx) ) {
                        DataFish fishData = new DataFish();

                        fishData.fishName = json_data.getString("SongName");
                        fishData.catName = json_data.getString("X");
                        fishData.sizeName = json_data.getString("Y");

                        data.add(fishData);

                    }
                }

                // Setup and Handover data to recyclerview


            } catch (JSONException e) {
                Toast.makeText(getActivity(), e.toString(), Toast.LENGTH_LONG).show();
            }

        }

    }


}

编辑：我还想指明我正在尝试将变量x和y添加到onPostExecute方法，我已经为x添加了一个值测试json输出是否正确。我希望x坐标来自TouchListener。

Answer 1

当活动/片段加载时，您确实应该只加载一次json文件，但是您可能希望在文件加载时显示一些进度条，并且片段尚未准备好接受用户触摸。（见this）

当文件完成下载后，你进入onPostExecute：

将jArray更改为类字段，并将new JSONArray(result);存储在其中，以便可以从班级的任何位置访问它。
隐藏您的进度条，并向用户显示真实的布局。

然后在onTouch实现中，使用jArray中的值来执行填充RecyclerView的循环（将代码从onPostExecute移动到onTouch侦听器）

将MotionEvent ActionDown坐标传递给内部类（AsyncTask）

1 个答案: