Is there a way prevent AlertDialog from closing with invalid inputs?

Question

I am using a simple text field alert dialog with a positive and a cancel button. I want to validate my alert dialog and prevent the done button from closing the AlertDialog

Answer 1

Here's how I did it. Technically, it doesn't technically keep the dialog open, it closes it momentarily and re-opens it, but the net result is the same.

class MyAlertDialog implements OnDismissListener, OnCancelListener {
    final private EditText editText;
    final private AlertDialog alertDialog;
    final private EventManager eventManager;
    final private CategorySelector categorySelector;

    private Boolean canceled;

    MyAlertDialog(Context context) {
        editText = new EditText(context);
        alertDialog = buildAlertDialog(context);
        alertDialog.setOnDismissListener(this);
        alertDialog.setOnCancelListener(this);
        show();
    }

    private AlertDialog buildAlertDialog(Context context) {
        return new AlertDialog.Builder(context)
        .setTitle(context.getString(R.string.enter_name))
        .setMessage(context.getString(R.string.enter_name))
        .setView(editText)
        .setNeutralButton(context.getString(R.string.save_text), null)
        .setNegativeButton(context.getString(R.string.cancel_text), null)
            .create();
    }

    public void show() {
        canceled = false;
        alertDialog.show();
    }

    @Override public void onDismiss(DialogInterface dialog) {
        if(!canceled) {
            final String name = editText.getText().toString();
            if(name.equals("")) {
                editText.setError("Please enter a non-empty name");
                show();
            } else {
                doWhateverYouWantHere(name);
            }
        }
    }

    @Override public void onCancel(DialogInterface dialog) {
        canceled = true;
    }
}