<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical" >
 
    <ImageView android:id="@+id/image_view_gallery" 
        android:layout_width="match_parent" 
	android:layout_height="match_parent"
	android:contentDescription="@string/gallery"/>
 
    <Gallery 
	android:id="@+id/gallery" 
	android:layout_width="match_parent"
	android:layout_height="wrap_content"
	android:layout_weight="0"/>
 
</LinearLayout>

 
import java.util.ArrayList;
 
import android.app.Activity;
import android.app.ProgressDialog;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.os.AsyncTask;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.AdapterView.OnItemSelectedListener;
import android.widget.Gallery;
import android.widget.ImageView;
import android.widget.Toast;
 
 
public class GalleryActivity extends Activity {
 
	private Gallery mGallery;
	private ImageView mImageView;
	private ProgressDialog mProgressDialog;
	private ArrayList<String> mImages = new ArrayList<String>();
	private int currentIndex;
	private GetImagesAsync getImagesAsync; 
 
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.gallery_layout);
 
		mGallery = (Gallery) findViewById(R.id.gallery);
		mImageView = (ImageView) findViewById(R.id.image_view_gallery);
 
		GalleryAdapter adapter = new GalleryAdapter(this);
		mGallery.setAdapter(adapter);
 
		mImageView.setImageResource(0);
 
		setViews();	
 
		getImagesAsync = new GetImagesAsync();
		getImagesAsync.execute((Void) null);
	}
 
	public void setView() {
		mGallery.setOnItemClickListener(new OnItemClickListener() {
			@Override
			public void onItemClick(AdapterView<?> arg0, View arg1, int arg2, long arg3) {
				mImageView.setImageURI(Uri.parse(mImages.get(arg2)));
			}
		});
 
		mGallery.setCallbackDuringFling(false);		
		mGallery.setOnItemSelectedListener(new OnItemSelectedListener() {
 
			@Override
			public void onItemSelected(AdapterView<?> arg0, View arg1, int arg2, long arg3) {
				mImageView.setImageURI(Uri.parse(mImages.get(arg2)));
			}
 
			@Override
			public void onNothingSelected(AdapterView<?> arg0) {
				// TODO Auto-generated method stub
			}
 
		});
	}
 
	public class GetImagesAsync extends AsyncTask<Void, Void, Boolean> {
		@Override
		protected void onPreExecute() {
			mProgressDialog = ProgressDialog.show(ImageAlbums.this,
					null, "Loading images...", true, false);
		}
 
		@Override 
		protected Boolean doInBackground(Void...voids) {
			result = getImages();
 
			return result;
		}
 
		@Override
		protected void onPostExecute(Boolean result) {
			mProgressDialog.dismiss();
			if(result) {
				adapter.setData(mImages);
				adapter.notifyDataSetChanged();	
			}else {
				Toast.makeText(SDImageGallery.this, "No SD card available", Toast.LENGTH_LONG).show();
			}
		}
	}
 
	private boolean getImages() {
 
		if(!isSdAvailable()){
			return false;
		}
 
		String[] projection = {MediaStore.Images.Media.DATA};
		String ord = MediaStore.Images.Media.DATA;
 
		ContentResolver cr = getContentResolver();
		Cursor mCursor = cr.query(MediaStore.Images.Media.EXTERNAL_CONTENT_URI, 
  				projection, 
  				null, 
  				null, 
  				ord + " ASC");	
 
  		if (mCursor != null && mCursor.moveToFirst()) 
  		{
			while(!mCursor.isAfterLast())
			{
	        		String data = mCursor.getString(mCursor.getColumnIndexOrThrow(ord));
	        		mImages.add(data);
	        		mCursor.moveToNext();
			}
			mCursor.close();
  		}
 
  		return true;
 
	}
 
	private boolean isSdAvailable()
	{
		boolean state = android.os.Environment.getExternalStorageState().equals(
				android.os.Environment.MEDIA_MOUNTED);
		return state;
	}
 
}

 
import android.content.Context;
import android.content.res.Resources;
import android.content.res.TypedArray;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.ImageView;
 
import java.util.ArrayList;
 
public class GalleryAdapter extends BaseAdapter{
 
	Context mContext;
	int mGalleryItemBackground;
	ArrayList<String> mImages = new ArrayList<String>();
	Resources resources;
 
	public GalleryAdapter(Context context) {
		mContext = context;
		TypedArray a = mContext.obtainStyledAttributes(R.styleable.Gallery1);
        	mGalleryItemBackground = a.getResourceId(R.styleable.Gallery1_android_galleryItemBackground, 0);
        	a.recycle();
        	resources = context.getResources();
	}
 
	@Override
	public int getCount() {
		return mImages.size();
	}
 
	@Override
	public String getItem(int index) {
		return mImages.get(index);
	}
 
	@Override
	public long getItemId(int id) {
		return id;
	}
 
	@Override
	public View getView(int position, View convertView, ViewGroup parent) {
		ImageView i = new ImageView(mContext);
 
		i.setImageURI(Uri.parse(mImages.get(position)));
		i.setLayoutParams(new Gallery.LayoutParams(resources.getDimension(R.dimen.mThumbnailWidth), resources.getDimension(R.dimen.mThumbnailHeight)));
		i.setBackgroundResource(mGalleryItemBackground);
 
    		return i;
	}
 
	public void setData(ArrayList<String> images) {
		mImages.addAll(images);
	}
 
	public void clearData() {
		mImages.clear();
	}
}

 
<resources>
 
    <dimen name="mThumbnailWidth">120dp</dimen>
    <dimen name="mThumbnailHeight">68dp</dimen>
 
</resources>

public class ImageFromWeb extends Activity {
 
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.image);
ImageView   image=(ImageView)findViewById(R.id.ImageView01);
Drawable drawable = LoadImageFromWebOperations("http://mywebsite.com/images/image.jpg");
image.setImageDrawable(drawable);
}/*as you can see there is a function used to load and make a drawable from a http link..so we need to make this function bellow*/
 
private Drawable LoadImageFromWebOperations(String url)
{
try
{
InputStream is = (InputStream) new URL(url).getContent();
Drawable d = Drawable.createFromStream(is, "src name");
return d;
}catch (Exception e) {
System.out.println("Exc="+e);
return null;
}
 }