Android : How to start a new activity while always keeping the gallery?

I am making a memory game using the gallery view. I want all the cards to be shown at the bottom and when the user picks one card from the gallery the particular card is displayed above it(in the image view). When the user touches this card, the card should turn (using flip animation) and the front of the card should be displayed (which should be a new activity). During this flip and all the time I want to display the gallery at the bottom. How can i do this? I have the following code which has no errors but the app crashes before starting. On viewing the log cat it suggests an error while starting the new acidity.

import android.app.Activity;
import android.content.Context;
import android.content.Intent;
import android.content.res.TypedArray;
import android.os.Bundle;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.BaseAdapter;
import android.widget.Gallery;
import android.widget.ImageView;
import android.widget.Toast;

public class GalleryActivity extends Activity { 
    //---the images to display---
    Integer[] imageIDs = {
            R.drawable.you,
            R.drawable.date,
            R.drawable.competition,
            R.drawable.contacts,
            R.drawable.memory,
            R.drawable.mission,
            R.drawable.recognition,
            R.drawable.report,
            R.drawable.stallion,
            R.drawable.strategy,
            R.drawable.team

    };
    ImageView youview;

    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        Gallery gallery = (Gallery) findViewById(R.id.gallery1);



        gallery.setAdapter(new ImageAdapter(this));
        gallery.setOnItemClickListener(new OnItemClickListener()
        {
            public void onItemClick(AdapterView<?> parent, View v,
            int position, long id)
            {
                Toast.makeText(getBaseContext(),
                        "card" + (position + 1) + " selected",
                        Toast.LENGTH_SHORT).show();

                //---display the images selected---
                ImageView imageView = (ImageView) findViewById(R.id.image1);
                imageView.setImageResource(imageIDs[position]);
            }
        });

        youview=(ImageView)findViewById(R.drawable.you);
        youview.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                // TODO Auto-generated method stub
                Intent intent = new Intent(GalleryActivity.this, You.class);
                startActivity(intent);
                }
        });
    }

    public class ImageAdapter extends BaseAdapter
    {
        Context context;
        int itemBackground;

        public ImageAdapter(Context c)
        {
            context = c;
            //---setting the style---
            TypedArray a = obtainStyledAttributes(R.styleable.Gallery1);            

            itemBackground = a.getResourceId(
                R.styleable.Gallery1_android_galleryItemBackground, 0);                

            a.recycle();
        }

        //---returns the number of images---
        public int getCount() {
            return imageIDs.length;
        }


        //---returns the item---
        public Object getItem(int position) {
            return position;
        }

         //---returns the ID of an item---
        public long getItemId(int position) {
            return position;
        }      

        //---returns an ImageView view---
        public View getView(int position, View convertView, ViewGroup parent) {
            ImageView imageView;
            if (convertView == null) {
                imageView = new ImageView(context);
                imageView.setImageResource(imageIDs[position]);
                imageView.setScaleType(ImageView.ScaleType.FIT_XY);
                imageView.setLayoutParams(new Gallery.LayoutParams(150, 120));                  
            } else {
                imageView = (ImageView) convertView;
            }            
            imageView.setBackgroundResource(itemBackground);
            return imageView;
        }
    }



}