Dismissing a modal dialog

Question

I am implementing a modal dialog in my Android application, allowing the user to either pick a player from a list, or create one with predefined traits.

PlayerPickerListener

public interface PlayerPickerListener {
    Activity getActivity();
    void playerCreated();
}

PlayerPicker (extends Dialog)

public PlayerPicker(Context context, String title, final PlayerPickerListener listener) {
    super(context);

    setTitle(title);
    setContentView(R.layout.player_dialog);

    View.OnClickListener changeHandler = new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            // PlayersActivity is basically a ListView selecting the player
            Intent intent = new Intent(listener.getActivity(), PlayersActivity.class);
            intent.putExtra(REQ_CODE, SELECT_ACTION);
            listener.getActivity().startActivityForResult(intent, SELECT_ACTION);
        }
    };

    Button b = (Button) findViewById(R.id.button_change);
    b.setOnClickListener(changeHandler);

    View.OnClickListener newHandler = new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            EntityPlayer player = PlayerManager.createNewPlayer();
            listener.playerCreated();
        }
    };
    b = (Button) findViewById(R.id.button_new);
    b.setOnClickListener(newHandler);

}

MainActivity (implements PlayerPickerListener)

public Activity getActivity() { return this; }

public void displayPlayer(View view) {
    myPlayerPicker = new PlayerPicker(this, "Pick a player", this);
    myPlayerPicker.show();
}

public void playerCreated() {
    myPlayerPicker.dismiss();
    // some extra stuff
}

@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
    if (requestCode == PlayersActivity.SELECT_ACTION && resultCode == RESULT_OK && data != null) {
        myPlayerPicker.dismiss();
        // some extra stuff
    }
    super.onActivityResult(requestCode, resultCode, data);
}

I have the following issues with my approach:

1. I am led to add the getActivity() method in my listener, because I have no other way of starting an intent from the Dialog. I need an intent to go to my ListView and return with a result.
2. Because of the above behavior, I am calling dismiss() on my Dialog from inside my Activity. For the new player case, I could easily add the dismissal of the Dialog inside the OnClickListener, but I am leaving it on the Activity just to have a type of uniform behavior.

My main question is whether it is common practice to dismiss a Dialog in its own code, or externally.

I'd argue that it would not seem natural for a dialog to be shut down from another source. A Dialog should disappear when its objective is complete. Is this bad design?

Answer 1

The code in general looks good, but here are a few observations:

1. Activity

   You can access the activity from the context as well. In your case, the context is actually the activity context. Therefore, you can cast to activity so that you can start an intent.

2. Dialog

   You can disable the dialog from wherever you want, depending on the needs. Disabling from inside is ok if, for example, you want to do something simple and return a callback to the caller and disable it immediately. Something simple and that's it, no complex operations involved, like rotation for example.

   If you want to handle rotations and other complicated operations as coming from memory, etc, then it might make sense to do it externally from the parent application, or from the application that started the dialog.