code to show alert dialog

showAlertDialog

    private void showAlertDialog() {
        AlertDialog.Builder builder = new AlertDialog.Builder(this);
        builder.setIcon(R.drawable.outline_error_24);
        builder.setTitle("Alert Dialog");
        builder.setMessage("This is an alert dialog.");
        builder.setPositiveButton("OK", (dialog, which) -> dialog.dismiss());
        builder.setNegativeButton("Cancel", new DialogInterface.OnClickListener() {
            @Override
            public void onClick(DialogInterface dialog, int which) {
                Toast.makeText(getBaseContext(), "Show Alert Dialog Canceled", Toast.LENGTH_SHORT).show();
                dialog.dismiss();
            }
        });

        AlertDialog alertDialog = builder.create();
        alertDialog.show();
    }