hi ,
i am making a app which takes photo on button click
i have camera.java which operates camera and takes photo
how to i call it on the below  event?
public void onClick(DialogInterface arg0, int arg1) {
setContentView(R.layout.startcamera);             
            }
Camera .java
package neuro.com;
import java.io.FileNotFoundException;
 import java.io.FileOutputStream;
 import java.io.IOException;
import android.app.Activity;
 import android.hardware.Camera;
 import android.hardware.Camera.PictureCallback;
 import android.hardware.Camera.ShutterCallback;
 import android.os.Bundle;
 import android.util.Log;
 import android.view.View;
 import android.view.View.OnClickListener;
 import android.widget.Button;
 import android.widget.FrameLayout;
public class CameraDemo extends Activity {
    private static final String TAG = "CameraDemo";
    Camera camera;
    Preview preview;
    Button buttonClick;
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.startcamera);
    preview = new Preview(this);
    ((FrameLayout) findViewById(R.id.preview)).addView(preview);
    buttonClick = (Button) findViewById(R.id.buttonClick);
    buttonClick.setOnClickListener( new OnClickListener() {
        public void onClick(View v) {
            preview.camera.takePicture(shutterCallback, rawCallback, jpegCallback);
        }
    });
    Log.d(TAG, "onCreate'd");
}
ShutterCallback shutterCallback = new ShutterCallback() {
    public void onShutter() {
        Log.d(TAG, "onShutter'd");
    }
};
/** Handles data for raw picture */
PictureCallback rawCallback = new PictureCallback() {
    public void onPictureTaken(byte[] data, Camera camera) {
        Log.d(TAG, "onPictureTaken - raw");
    }
};
/** Handles data for jpeg picture */
PictureCallback jpegCallback = new PictureCallback() {
    public void onPictureTaken(byte[] data, Camera camera) {
        FileOutputStream outStream = null;
        try {
            // write to local sandbox file system
//              outStream = CameraDemo.this.openFileOutput(String.format("%d.jpg", System.currentTimeMillis()), 0); 
                // Or write to sdcard
                outStream = new FileOutputStream(String.format("/sdcard/%d.jpg", System.currentTimeMillis()));
                outStream.write(data);
                outStream.close();
                Log.d(TAG, "onPictureTaken - wrote bytes: " + data.length);
            } catch (FileNotFoundException e) {
                e.printStackTrace();
            } catch (IOException e) {
                e.printStackTrace();
            } finally {
            }
            Log.d(TAG, "onPictureTaken - jpeg");
        }
    };
}