Question

请帮帮我。

在我的列表视图中，我显示数据库中的图像和文本。

我遇到了问题。

当我使用.php文件时，不会显示图像。当我尝试复制我的php的结果以保存到.txt文件并更改我的URL时，图像可以正常工作。

我的问题是我想使用.php文件显示图像。

这是代码。

CategoryFragment.java

package com.example.administrator.mosbeau;

import android.app.Activity;
import android.app.Fragment;
import android.app.FragmentManager;
import android.app.ProgressDialog;
import android.os.AsyncTask;
import android.os.Bundle;
import android.support.annotation.Nullable;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.EditText;
import android.widget.ExpandableListView;
import android.widget.ListView;

import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.NameValuePair;
import org.apache.http.client.HttpClient;
import org.apache.http.client.entity.UrlEncodedFormEntity;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.message.BasicNameValuePair;
import org.apache.http.params.BasicHttpParams;
import org.apache.http.params.HttpConnectionParams;
import org.apache.http.params.HttpParams;
import org.apache.http.util.EntityUtils;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;

import java.io.BufferedReader;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;

/**
 * Created by Administrator on 9/18/2015.
 */
public class CategoryFragment extends Fragment {

    public static CategoryFragment newInstance(String id,String name) {
        CategoryFragment fragment = new CategoryFragment();

        Bundle bundle = new Bundle();
        bundle.putString("id", id);
        bundle.putString("name", name);
        fragment.setArguments(bundle);

        return fragment;
    }

    public CategoryFragment () {
    }

    EditText tpid, tpname;
    String cid;
    String cname;

    String myJSON;
    JSONObject jsonobject;
    JSONArray jsonarray;
    ListView productlistview;
    ListViewAdapter adapter;
    ProgressDialog mProgressDialog;
    ArrayList<HashMap<String, String>> arraylist;
    public static String products_id = "products_id";
    public static String products_name = "products_name";
    public static String products_price = "products_price";
    public static String products_image = "products_image";

    Boolean InternetAvailable = false;
    Seocnd detectconnection;

    @Nullable
    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState){
        View rootView = inflater.inflate(R.layout.categorylayout, container, false);

        getActivity().invalidateOptionsMenu();

        tpid = (EditText) rootView.findViewById(R.id.tpid);
        tpname = (EditText) rootView.findViewById(R.id.tpname);

        if(getArguments() != null) {
            String catid = getArguments().getString("id");
            String catname = getArguments().getString("name");

            tpid.setText(catid);
            tpname.setText(catname);
            cid = catid;
            cname = catname;
        }

        productlistview = (ListView) rootView.findViewById(R.id.productlistview);

        //new DownloadJSON().execute();

        detectconnection = new Seocnd(getActivity());
        InternetAvailable = detectconnection.InternetConnecting();
        if (InternetAvailable) {
            getProduct();
        } else {
            NointernetFragment fragment = new NointernetFragment();
            FragmentManager fragmentManager = getFragmentManager();
            fragmentManager.beginTransaction()
                    .replace(R.id.container, fragment)
                    .commit();
        }

        return rootView;
    }

    public void getProduct(){
        class DownloadJSON extends AsyncTask<String, Void, String> {

            @Override
            protected void onPreExecute() {
                super.onPreExecute();
                // Create a progressdialog
                mProgressDialog = new ProgressDialog(getActivity());
                // Set progressdialog title
                mProgressDialog.setTitle(cname);
                // Set progressdialog message
                mProgressDialog.setMessage("Loading...");
                mProgressDialog.setIndeterminate(false);
                // Show progressdialog
                mProgressDialog.show();
            }

            @Override
            protected String doInBackground(String... params) {
                DefaultHttpClient httpclient = new DefaultHttpClient(new BasicHttpParams());
                HttpPost httppost = new HttpPost("http://joehamirbalabadan.com/android/android/products.php");

                // Depends on your web service
                httppost.setHeader("Content-type", "application/json");

                InputStream inputStream = null;
                String result = null;
                try {
                    HttpResponse response = httpclient.execute(httppost);
                    HttpEntity entity = response.getEntity();

                    inputStream = entity.getContent();
                    // json is UTF-8 by default
                    BufferedReader reader = new BufferedReader(new InputStreamReader(inputStream, "UTF-8"), 8);
                    StringBuilder sb = new StringBuilder();

                    String line = null;
                    while ((line = reader.readLine()) != null)
                    {
                        sb.append(line + "\n");
                    }
                    result = sb.toString();
                } catch (Exception e) {
                    // Oops
                }
                finally {
                    try{if(inputStream != null)inputStream.close();}catch(Exception squish){}
                }
                return result;
            }

            @Override
            protected void onPostExecute(String result){
                myJSON=result;

                try {
                    // Locate the array name in JSON
                    JSONObject jsonObj = new JSONObject(myJSON);
                    jsonarray = jsonObj.getJSONArray("products");

                    arraylist = new ArrayList<HashMap<String, String>>();

                    for (int i = 0; i < jsonarray.length(); i++) {
                        HashMap<String, String> map = new HashMap<String, String>();
                        JSONObject p = jsonarray.getJSONObject(i);
                        // Retrive JSON Objects
                        map.put("products_id", p.getString("products_id"));
                        map.put("products_name", p.getString("products_name"));
                        map.put("products_price", p.getString("products_price"));
                        map.put("products_image", p.getString("products_image"));
                        // Set the JSON Objects into the array
                        arraylist.add(map);
                    }
                } catch (JSONException e) {
                    Log.e("Error", e.getMessage());
                    e.printStackTrace();
                }

                adapter = new ListViewAdapter(getActivity(), arraylist);
                // Set the adapter to the ListView
                productlistview.setAdapter(adapter);
                // Close the progressdialog
                mProgressDialog.dismiss();
            }
        }
        DownloadJSON g = new DownloadJSON();
        g.execute();
    }

    @Override
    public void onAttach(Activity activity) {
        super.onAttach(activity);
        ((MainActivity) activity).onSectionAttached(2);
    }
}

ListViewAdapter.java

package com.example.administrator.mosbeau;

/**
 * Created by Administrator on 9/28/2015.
 */

import android.content.Context;
import android.content.Intent;
import android.view.LayoutInflater;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.ImageView;
import android.widget.TextView;

import java.util.ArrayList;
import java.util.HashMap;

public class ListViewAdapter extends BaseAdapter {

    // Declare Variables
    Context context;
    LayoutInflater inflater;
    ArrayList<HashMap<String, String>> data;
    ImageLoader imageLoader;
    HashMap<String, String> resultp = new HashMap<String, String>();

    public ListViewAdapter(Context context,
                           ArrayList<HashMap<String, String>> arraylist) {
        this.context = context;
        data = arraylist;
        imageLoader = new ImageLoader(context);
    }

    @Override
    public int getCount() {
        return data.size();
    }

    @Override
    public Object getItem(int position) {
        return null;
    }

    @Override
    public long getItemId(int position) {
        return 0;
    }

    public View getView(final int position, View convertView, ViewGroup parent) {
        // Declare Variables
        TextView products_id;
        TextView products_name;
        TextView products_price;
        ImageView products_image;

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

        View itemView = inflater.inflate(R.layout.product_listview_item, parent, false);
        // Get the position
        resultp = data.get(position);

        // Locate the TextViews in product_listview_item.xml
        products_id = (TextView) itemView.findViewById(R.id.products_id);
        products_name = (TextView) itemView.findViewById(R.id.products_name);
        products_price = (TextView) itemView.findViewById(R.id.products_price);

        // Locate the ImageView in product_listview_item.xml
        products_image = (ImageView) itemView.findViewById(R.id.products_image);

        // Capture position and set results to the TextViews
        products_id.setText(resultp.get(CategoryFragment.products_id));
        products_name.setText(resultp.get(CategoryFragment.products_name));
        products_price.setText(resultp.get(CategoryFragment.products_price));
        // Capture position and set results to the ImageView
        // Passes flag images URL into ImageLoader.class
        imageLoader.DisplayImage(resultp.get(CategoryFragment.products_image), products_image);
        // Capture ListView item click
        itemView.setOnClickListener(new OnClickListener() {

            @Override
            public void onClick(View arg0) {
                // Get the position
                resultp = data.get(position);
                Intent intent = new Intent(context, SingleItemView.class);
                // Pass all data rank
                intent.putExtra("products_id", resultp.get(CategoryFragment.products_id));
                // Pass all data country
                intent.putExtra("products_name", resultp.get(CategoryFragment.products_name));
                // Pass all data population
                intent.putExtra("products_price",resultp.get(CategoryFragment.products_price));
                // Pass all data flag
                intent.putExtra("products_image", resultp.get(CategoryFragment.products_image));
                // Start SingleItemView Class
                context.startActivity(intent);

            }
        });
        return itemView;
    }
}

ImageLoader.java

package com.example.administrator.mosbeau;

/**
 * Created by Administrator on 9/28/2015.
 */

import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.os.Handler;
import android.widget.ImageView;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.HttpURLConnection;
import java.net.URL;
import java.util.Collections;
import java.util.Map;
import java.util.WeakHashMap;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;

public class ImageLoader {

    MemoryCache memoryCache = new MemoryCache();
    FileCache fileCache;
    private Map<ImageView, String> imageViews = Collections
            .synchronizedMap(new WeakHashMap<ImageView, String>());
    ExecutorService executorService;
    // Handler to display images in UI thread
    Handler handler = new Handler();

    public ImageLoader(Context context) {
        fileCache = new FileCache(context);
        executorService = Executors.newFixedThreadPool(5);
    }

    final int stub_id = R.drawable.temp_img;

    public void DisplayImage(String url, ImageView imageView) {
        imageViews.put(imageView, url);
        Bitmap bitmap = memoryCache.get(url);
        if (bitmap != null)
            imageView.setImageBitmap(bitmap);
        else {
            queuePhoto(url, imageView);
            imageView.setImageResource(stub_id);
        }
    }

    private void queuePhoto(String url, ImageView imageView) {
        PhotoToLoad p = new PhotoToLoad(url, imageView);
        executorService.submit(new PhotosLoader(p));
    }

    private Bitmap getBitmap(String url) {
        File f = fileCache.getFile(url);

        Bitmap b = decodeFile(f);
        if (b != null)
            return b;

        // Download Images from the Internet
        try {
            Bitmap bitmap = null;
            URL imageUrl = new URL(url);
            HttpURLConnection conn = (HttpURLConnection) imageUrl
                    .openConnection();
            conn.setConnectTimeout(30000);
            conn.setReadTimeout(30000);
            conn.setInstanceFollowRedirects(true);
            InputStream is = conn.getInputStream();
            OutputStream os = new FileOutputStream(f);
            Utils.CopyStream(is, os);
            os.close();
            conn.disconnect();
            bitmap = decodeFile(f);
            return bitmap;
        } catch (Throwable ex) {
            ex.printStackTrace();
            if (ex instanceof OutOfMemoryError)
                memoryCache.clear();
            return null;
        }
    }

    // Decodes image and scales it to reduce memory consumption
    private Bitmap decodeFile(File f) {
        try {
            // Decode image size
            BitmapFactory.Options o = new BitmapFactory.Options();
            o.inJustDecodeBounds = true;
            FileInputStream stream1 = new FileInputStream(f);
            BitmapFactory.decodeStream(stream1, null, o);
            stream1.close();

            // Find the correct scale value. It should be the power of 2.
            // Recommended Size 512
            final int REQUIRED_SIZE = 70;
            int width_tmp = o.outWidth, height_tmp = o.outHeight;
            int scale = 1;
            while (true) {
                if (width_tmp / 2 < REQUIRED_SIZE
                        || height_tmp / 2 < REQUIRED_SIZE)
                    break;
                width_tmp /= 2;
                height_tmp /= 2;
                scale *= 2;
            }

            // Decode with inSampleSize
            BitmapFactory.Options o2 = new BitmapFactory.Options();
            o2.inSampleSize = scale;
            FileInputStream stream2 = new FileInputStream(f);
            Bitmap bitmap = BitmapFactory.decodeStream(stream2, null, o2);
            stream2.close();
            return bitmap;
        } catch (FileNotFoundException e) {
        } catch (IOException e) {
            e.printStackTrace();
        }
        return null;
    }

    // Task for the queue
    private class PhotoToLoad {
        public String url;
        public ImageView imageView;

        public PhotoToLoad(String u, ImageView i) {
            url = u;
            imageView = i;
        }
    }

    class PhotosLoader implements Runnable {
        PhotoToLoad photoToLoad;

        PhotosLoader(PhotoToLoad photoToLoad) {
            this.photoToLoad = photoToLoad;
        }

        @Override
        public void run() {
            try {
                if (imageViewReused(photoToLoad))
                    return;
                Bitmap bmp = getBitmap(photoToLoad.url);
                memoryCache.put(photoToLoad.url, bmp);
                if (imageViewReused(photoToLoad))
                    return;
                BitmapDisplayer bd = new BitmapDisplayer(bmp, photoToLoad);
                handler.post(bd);
            } catch (Throwable th) {
                th.printStackTrace();
            }
        }
    }

    boolean imageViewReused(PhotoToLoad photoToLoad) {
        String tag = imageViews.get(photoToLoad.imageView);
        if (tag == null || !tag.equals(photoToLoad.url))
            return true;
        return false;
    }

    // Used to display bitmap in the UI thread
    class BitmapDisplayer implements Runnable {
        Bitmap bitmap;
        PhotoToLoad photoToLoad;

        public BitmapDisplayer(Bitmap b, PhotoToLoad p) {
            bitmap = b;
            photoToLoad = p;
        }

        public void run() {
            if (imageViewReused(photoToLoad))
                return;
            if (bitmap != null)
                photoToLoad.imageView.setImageBitmap(bitmap);
            else
                photoToLoad.imageView.setImageResource(stub_id);
        }
    }

    public void clearCache() {
        memoryCache.clear();
        fileCache.clear();
    }

}

这是结果..

products.php

products.txt

Answer 1

好像你的imageLoader类有问题，我建议使用Picasso代替这种自定义方法，它速度非常快，并且还可以自动管理您的网络操作。

 Picasso.with(GazuntiteMainActivity.context).load(urldisplay).placeholder(R.drawable.image_loader).into(bmImage);

此处占位符中，将显示此图像，直到下载远程图像。

Android Studio ListView图像无法显示

1 个答案: