how to get bitmap image from hashtable into simple adapter to view in imageview for listactivity

Question

Below is my code. I am getting url for an image through JSONArray. Then i converted the image to Bitmap image and stored in Hashtable.

I am using ImageView to show the images in listview. So i am using simple adapter for getting images. But image is not loading.

Please help me out of this, I am new to Android!!!!!!

ArrayList<Hashtable<String, Bitmap>> mylist1 = new ArrayList<Hashtable<String, Bitmap>>();

try{                
    JSONArray  earthquakes = json.getJSONArray("earthquakes");              
    for(int i=0;i<10;i++){                      
        imagemap = new Hashtable<String, Bitmap>();
        JSONObject e = earthquakes.getJSONObject(i);
        try
        {
            aURL = new URL(photo);
        }
        catch (MalformedURLException e1)
        {
            // TODO Auto-generated catch block
            e1.printStackTrace();
        }
        URLConnection conn = null;
        try
        {
            conn = aURL.openConnection();
        }
        catch (IOException e1)
        {
            // TODO Auto-generated catch block
            e1.printStackTrace();
        }
        try
        {
            conn.connect();
        }
        catch (IOException e1)
        {
            // TODO Auto-generated catch block
            e1.printStackTrace();
        }
        InputStream is = null;
        try
        {
            is = conn.getInputStream();
        }
        catch (IOException e1)
        {
            // TODO Auto-generated catch block
            e1.printStackTrace();
        }
        BufferedInputStream bis = new

        BufferedInputStream(is,8*1024);

        Bitmap bm = BitmapFactory.decodeStream(bis);

        imagemap.put("im",bm);

        mylist1.add(imagemap);
        ListAdapter adapter = new SimpleAdapter(this,mylist1,R.layout.main,new String[] {"im"},new int[] {R.id.image});

        setListAdapter(adapter);

Update:

Below is the ArrayAdapter i used to load the string to text fields in the listview. I have one ImageView in it. How to override the listadapter to load the dynamic images into the listview.

ListAdapter adapter = new SimpleAdapter(this, mylist , R.layout.main4, 
                       new String[] { "percent","propertyid",  "cityname", "statecode", "propertytype", "footage", "bathroom", "bedroom", "price", "estimated" }, 
                        new int[] { R.id.percent, R.id.property_id,  R.id.city_name, R.id.state_code, R.id.prop_type, R.id.foot, R.id.bath, R.id.bed, R.id.list, R.id.estimat});

setListAdapter(adapter);

pintaf · Answer 1 · 2014-08-15T15:32:09.647

Basically the simple adapter automatically bind some ressource id or URI to the imageview of your row layout. But it don't support Bitmap.

That's a problem, because everyone who had to manage bitmap know that we often have to reduce the size of the picture to prevent outOfMemory exceptions. But if you want to add images into a listView, you cannot reduce the image's size if you only provide URI. So here is the solution :

I have modified the simpleAdapter to be able to handle bitmap. Add this class into your project, and use it instead of simpleAdapter. Then instead of passing an URI or a ressourceId for an image, pass a Bitmap !

Hereunder is the code :

import java.util.HashMap;
import java.util.List;
import java.util.Map;

import android.content.Context;
import android.graphics.Bitmap;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Checkable;
import android.widget.ImageView;
import android.widget.SimpleAdapter;
import android.widget.TextView;



public class ExtendedSimpleAdapter extends SimpleAdapter{
    List<? extends Map<String, ?>> map; // if fails to compile, replace with List<HashMap<String, Object>> map
    String[] from;
    int layout;
    int[] to;
    Context context;
    LayoutInflater mInflater;
    public ExtendedSimpleAdapter(Context context, List<? extends Map<String, ?>> data, // if fails to compile, do the same replacement as above on this line
            int resource, String[] from, int[] to) { 
        super(context, data, resource, from, to);
        layout = resource;
        map = data;
        this.from = from;
        this.to = to;
        this.context = context;
    }


@Override
public View getView(int position, View convertView, ViewGroup parent) {
    mInflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
    return this.createViewFromResource(position, convertView, parent, layout);
}

private View createViewFromResource(int position, View convertView,
        ViewGroup parent, int resource) {
    View v;
    if (convertView == null) {
        v = mInflater.inflate(resource, parent, false);
    } else {
        v = convertView;
    }

    this.bindView(position, v);

    return v;
}


private void bindView(int position, View view) {
    final Map dataSet = map.get(position);
    if (dataSet == null) {
        return;
    }

    final ViewBinder binder = super.getViewBinder();
    final int count = to.length;

    for (int i = 0; i < count; i++) {
        final View v = view.findViewById(to[i]);
        if (v != null) {
            final Object data = dataSet.get(from[i]);
            String text = data == null ? "" : data.toString();
            if (text == null) {
                text = "";
            }

            boolean bound = false;
            if (binder != null) {
                bound = binder.setViewValue(v, data, text);
            }

            if (!bound) {
                if (v instanceof Checkable) {
                    if (data instanceof Boolean) {
                        ((Checkable) v).setChecked((Boolean) data);
                    } else if (v instanceof TextView) {
                        // Note: keep the instanceof TextView check at the bottom of these
                        // ifs since a lot of views are TextViews (e.g. CheckBoxes).
                        setViewText((TextView) v, text);
                    } else {
                        throw new IllegalStateException(v.getClass().getName() +
                                " should be bound to a Boolean, not a " +
                                (data == null ? "<unknown type>" : data.getClass()));
                    }
                } else if (v instanceof TextView) {
                    // Note: keep the instanceof TextView check at the bottom of these
                    // ifs since a lot of views are TextViews (e.g. CheckBoxes).
                    setViewText((TextView) v, text);
                } else if (v instanceof ImageView) {
                    if (data instanceof Integer) {
                        setViewImage((ImageView) v, (Integer) data);                            
                    } else if (data instanceof Bitmap){
                        setViewImage((ImageView) v, (Bitmap)data);
                    } else {
                        setViewImage((ImageView) v, text);
                    }
                } else {
                    throw new IllegalStateException(v.getClass().getName() + " is not a " +
                            " view that can be bounds by this SimpleAdapter");
                }
            }
        }
    }
}



private void setViewImage(ImageView v, Bitmap bmp){
    v.setImageBitmap(bmp);
}



}

This class behave exactly like the original class (SimpleAdapter)

score 0 · Accepted Answer · edited May 23 '17 at 12:19

This is how I put an image inside a listview

public View getView(int position, View convertView, ViewGroup parent) {
    View vi=convertView;
    ViewHolder holder;
    if(convertView==null){
        vi = inflater.inflate(R.layout.highscore_item, null);
        holder=new ViewHolder();
        holder.Icon=(ImageView)vi.findViewById(R.id.icon);
        vi.setTag(holder);
    }
    else
        holder=(ViewHolder)vi.getTag();
    holder.Icon.setTag(mData[position].getIcon());
    imageLoader.DisplayImage(mData[position].getIcon(), activity, holder.Icon);
    return vi;
}

Take a look at Lazylist if you want more info.

how to get bitmap image from hashtable into simple adapter to view in imageview for listactivity

Update:

2 Answers2