Question

I get trouble when I created one form and one midlet and I want through an alert for user when user enters detail, but I got trouble it can’t change screen to show alert

Answer 1

nothing can be easier with the code provided in rev 4 of your question

// ... your AddReview class

    public AddReview(String title, MainFoodie mf) {
        super(title);
        this.mf = mf; // without that you'll get NPE in changeSreen
        // ...
    }

    //...
    private void changeScreen(Alert a, Form f){
        Display.getDisplay(mf).setCurrent(a, f);
    }

    public void commandAction(Command c, Displayable d) {
       if(c.getLabel().equals("Save")){
           // how to show alert here:
           changeScreen(cfmAlert, this)
       }