* @throws IOException if there is an I/O error.
*/
public void doSaveAs() throws IOException {
JFileChooser fileChooser = new JFileChooser();
ExtensionFileFilter filter =
new ExtensionFileFilter(localizationResources.getString("PNG_Image_Files"), ".png");
fileChooser.addChoosableFileFilter(filter);
fileChooser.addChoosableFileFilter(new ExtensionFileFilter("All files", ""));
int option = fileChooser.showSaveDialog(this);
if (option == JFileChooser.APPROVE_OPTION) {
String filename = fileChooser.getSelectedFile().getPath();
if (isEnforceFileExtensions()) {