Android “Best Practice” returning values from a dialog

Perhaps I’m mis-understanding your question, but why not just use the built in listener system:

builder.setPositiveButton("Yes", new DialogInterface.OnClickListener() {
    public void onClick(DialogInterface dialog, int id) {
        // run whatever code you want to run here
        // if you need to pass data back, just call a function in your
        // activity and pass it some parameters
    }
})

This is how I’ve always handled data from dialog boxes.

EDIT: Let me give you a more concrete example which will better answer your question. I’m going to steal some sample code from this page, which you should read:

http://developer.android.com/guide/topics/ui/dialogs.html

// Alert Dialog code (mostly copied from the Android docs
AlertDialog.Builder builder = new AlertDialog.Builder(this);
builder.setTitle("Pick a color");
builder.setItems(items, new DialogInterface.OnClickListener() {
    public void onClick(DialogInterface dialog, int item) {
        myFunction(item);
    }
});
AlertDialog alert = builder.create();

…

// Now elsewhere in your Activity class, you would have this function
private void myFunction(int result){
    // Now the data has been "returned" (as pointed out, that's not
    // the right terminology)
}