* Displays the {@link StartupDialog} dialog and, if the user provides login credentials,
* logs into the S3 service using those credentials.
*/
private void loginEvent() {
try {
StartupDialog startupDialog = new StartupDialog(ownerFrame, this);
startupDialog.setVisible(true);
AWSCredentials awsCredentials = startupDialog.getAWSCredentials();
startupDialog.dispose();
s3ServiceMulti = new S3ServiceMulti(
new RestS3Service(awsCredentials, APPLICATION_DESCRIPTION, this), this);
if (awsCredentials == null) {