Android : how Custom Dialog returns intent result to parent activity

In my mainactivity class, on clicking a button, it displays a dialog that shows, "capture a photo", "capture a video", pick from gallery" buttons upon clicking any of those button it has to do the respective action and return the path of file to mainactivity. It is easy to do with startActivityForResult&onActivityResult within mainactivity. But how can I use intent with in custom dialog and return the intent result from custom dialog to mainactivity.

Thanks for your time.

takeaPhoto.setOnClickListener(new View.OnClickListener() {
    @Override
    public void onClick(View v) {
        Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
        startActivityForResult(intent, ACTION_TAKE_PHOTO);
    }
});

public void onActivityResult(int requestCode, int resultCode, Intent data) { 
    switch(){
        //do action
        String filePath = data.getDataString();
        filename.setText(filePath);
    }
}

It's not tough. Just use alert Dialog and make sure that your views are right.

final Context context = this;
static final int SELECT_PICTURE = 1; 

takeaphoto.setOnClickListener(new View.OnClickListener() {
public void onClick(View v){  

LayoutInflater myLayout = LayoutInflater.from(context);
final View dialogView = myLayout.inflate(R.layout.YOURCUSTOM.XML, null);
AlertDialog.Builder alertDialogBuilder = new AlertDialog.Builder(context);
alertDialogBuilder.setView(dialogView);
final AlertDialog alertDialog = alertDialogBuilder.create();        


Button button1 = (Button) dialogView.findViewById(R.id.button1);
button1.setOnClickListener(new OnClickListener(){
public void onClick(View v) {


Intent intent = new Intent(Intent.ACTION_PICK);
intent.setType("image/*");
intent.setAction(Intent.ACTION_GET_CONTENT);
startActivityForResult(intent, SELECT_PICTURE);
}});

alertDialog.show();
return;}});