图像随机变化

Question

我有以下问题：

我有一个显示很多 ImageView 的 GridView，如果我开始滚动，项目会随机开始更改，因此错误的图像会出现在错误的位置，并且它们每次都会从位置到位置。

ImageAdapter

package com.zippyscore.pr0gramm.Adapter;

import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.os.AsyncTask;
import android.util.Log;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.ImageView;

import com.zippyscore.pr0gramm.MainActivity;
import com.zippyscore.pr0gramm.Util.Constants;

import java.io.InputStream;

/**
 * Created by Dominik on 16.01.2015.
 */
public class ImageAdapter extends BaseAdapter {
    private Context mContext;

    public ImageAdapter(Context c) {
        mContext = c;
    }

    public int getCount() {
        return MainActivity.mainPagePostLoader.getPostList().size();
    }

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

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

    // create a new ImageView for each item referenced by the Adapter
    public View getView(int position, View convertView, ViewGroup parent) {
        ViewHolder vh;
        if (convertView == null) {
            convertView = new ImageView(mContext);
            vh = new ViewHolder();
            vh.imageView = (ImageView) convertView;
            convertView.setTag(vh);
        } else {
            vh = (ViewHolder) convertView.getTag();
        }
        new DownloadImageTask(vh.imageView).execute(MainActivity.mainPagePostLoader.getPosts().get(MainActivity.mainPagePostLoader.getPostList().get(position)).getThumb());
        return convertView;
    }


    protected class DownloadImageTask extends AsyncTask<String, Void, Bitmap> {
        ImageView bmImage;

        public DownloadImageTask(ImageView bmImage) {
            this.bmImage = bmImage;
        }

        protected Bitmap doInBackground(String... urls) {
            String urldisplay = "http://" + Constants.THUMB_DOMAIN + urls[0];
            Bitmap mIcon11 = null;
            try {
                InputStream in = new java.net.URL(urldisplay).openStream();
                mIcon11 = BitmapFactory.decodeStream(in);
            } catch (Exception e) {
                Log.e("Pr0gramm", e.getMessage());
                e.printStackTrace();
            }
            return mIcon11;
        }

        protected void onPostExecute(Bitmap result) {
            bmImage.setImageBitmap(result);
        }
    }


    private class ViewHolder{

        public ViewHolder(){}

        public ImageView imageView;
        //public TextView textView;
        //Add any views you want to use in getView here
    }


}

MainPagePostLoader(应该无关紧要)

package com.zippyscore.pr0gramm.Network;

import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Point;
import android.os.AsyncTask;
import android.util.Log;
import android.view.WindowManager;
import android.widget.ImageView;
import android.widget.RelativeLayout;

import com.zippyscore.pr0gramm.CustomViews.ThumbImageView;
import com.zippyscore.pr0gramm.MainActivity;
import com.zippyscore.pr0gramm.Post.MainPagePost;
import com.zippyscore.pr0gramm.Util.GridRow;

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

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

/**
 * Created by Dominik on 13.01.2015.
 */
public class MainPagePostLoader{
    int chunksLoaded;
    int lastPromoted;
    private HashMap<String, MainPagePost> posts = new HashMap<String, MainPagePost>();
    private List<String> postList = new ArrayList<String>();
    private NetworkHelper networkHelper;

    public MainPagePostLoader(){
        chunksLoaded = 0;
        lastPromoted = 0;
        networkHelper = new NetworkHelper();
    }

    public HashMap<String, MainPagePost> getPosts(){
        return this.posts;
    }

    public List<String> getPostList(){
        return this.postList;
    }

    public void loadNextChunk(){
        if(chunksLoaded==0){
            String serverResponse = networkHelper.connect("http://pr0gramm.com/api/items/get?flags=1&promoted=1"); //TODO ADD FLAG SUPPORT
            if(serverResponse!=null){
                try {
                    JSONObject serverResponseJSON = new JSONObject(serverResponse);
                    if(serverResponseJSON.has("items")) {
                        JSONArray postsJSON = serverResponseJSON.getJSONArray("items");
                        for(int i = 0; i < postsJSON.length();i++){
                            JSONObject post = postsJSON.getJSONObject(i);
                            posts.put(String.valueOf(post.getInt("id")),new MainPagePost(post.getInt("id"),post.getInt("promoted"),post.getInt("up"), post.getInt("down"), post.getLong("created"), post.getString("image"),post.getInt("flags"),post.getInt("mark"), post.getString("source"),post.getString("thumb"),post.getString("user")));
                            postList.add(String.valueOf(post.getInt("id")));
                            MainActivity.activity.runOnUiThread(new Runnable() {
                                @Override
                                public void run() {
                                    MainActivity.imageAdapter.notifyDataSetChanged();
                                }
                            });
                            //addThumb(i);
                        }


                    }
                    chunksLoaded++;
                } catch (JSONException e) {
                    Log.e("Pr0gramm","JSON Parse error : " + e.getMessage() + "|" + e.getCause());
                }
            }else{
                Log.e("Pr0gramm", "Chunk loading error");
            }

        }else{
            try {
                String serverResponse = networkHelper.connect("http://pr0gramm.com/api/items/get?older=" + String.valueOf(posts.get(postList.size() - 1).getID()));
                JSONObject serverResponseJSON = new JSONObject(serverResponse);
               if(serverResponseJSON.has("items")){
                   JSONArray postsJSON = serverResponseJSON.getJSONArray("items");
                   for(int i = 0; i < postsJSON.length();i++){
                       JSONObject post = postsJSON.getJSONObject(i);
                       posts.put(String.valueOf(post.getInt("id")),new MainPagePost(post.getInt("id"),post.getInt("promoted"),post.getInt("up"), post.getInt("down"), post.getLong("created"), post.getString("image"),post.getInt("flags"),post.getInt("mark"), post.getString("source"),post.getString("thumb"),post.getString("user")));
                       postList.add(String.valueOf(post.getInt("id")));
                       MainActivity.imageAdapter.notifyDataSetChanged();
                       //addThumb(i + (postList.size()-1));
                   }
               }
                chunksLoaded++;
            }catch(JSONException e){
                Log.e("Pr0gramm", "JSON Parse error : " + e.getMessage() + "|" + e.getCause());
            }
        }
    }

/*
    private void addThumb(int id){
        int currentRow = MainActivity.gridRows.size() - 1;
        Point size = new Point();
        MainActivity.defaultDisplay.getSize(size);
        if(currentRow!=-1) {
            if (MainActivity.gridRows.get(currentRow).getItemCount() < MainActivity.maxItemsPerRow) {
                final ThumbImageView thumbImageView = new ThumbImageView(MainActivity.context, id);
                thumbImageView.setLayoutParams(new RelativeLayout.LayoutParams(size.x / MainActivity.maxItemsPerRow, size.x / MainActivity.maxItemsPerRow));
                thumbImageView.setX(MainActivity.gridRows.get(currentRow).getItemCount() * size.x / MainActivity.maxItemsPerRow);
                thumbImageView.setY(currentRow * size.x / MainActivity.maxItemsPerRow);
                MainActivity.activity.runOnUiThread(new Runnable() {
                    @Override
                    public void run() {
                        MainActivity.rootLayout.addView(thumbImageView);
                    }
                });
                MainActivity.gridRows.get(currentRow).addItem();
            } else {
                MainActivity.gridRows.add(new GridRow());
                addThumb(id);
            }
        }else{
            MainActivity.gridRows.add(new GridRow());
            addThumb(id);
        }
    } */
}

Answer 1

考虑为此使用 Square Picasso 库，而不是自己动手：

http://square.github.io/picasso/

图像随机变化

Images randomly change

android

android-imageview

android-gridview