Vaadin addStyleName problem - vaadin

Question

I created a TextField with TextChangeListener. When user types in certain values (in this case 'admin') then addStyleName is invoked on that field and font color becomes red. But afterwards, the value is blank and each entered character is being cleared.
Here is the code of the application. Why after adding new style to TextField its value changes?
public class VaadintestApplication extends Application {
#Override
public void init() {
Window mainWindow = new Window("Vaadintest Application");
setTheme("test");
TextField textField = new TextField("username");
textField.setEnabled(true);
textField.setTextChangeEventMode(TextChangeEventMode.EAGER);
textField.addListener(new TextChangeListener() {
public void textChange(TextChangeEvent event) {
if ("admin".equals(event.getText())) {
((TextField) event.getComponent()).addStyleName("text-error");
} else {
((TextField) event.getComponent()).removeStyleName("text-error");
}
}
});
mainWindow.addComponent(textField);
setMainWindow(mainWindow);
}
}

Answer 1

I would guess that the following happens:
The style name change triggers a repaint on the server, causing the TextField component to be serialized again to the client
The client receives the serialization (the whole bloody thing, not just the changed parts, because that's how things work with Vaadin), and hence it changes the contents of the textfield, while ignoring any changes that are pending from the text change listener
Solutions:
Update the value of the TextField at the same time you add/remove the style name: ((TextField) event.getComponent()).setValue(event.getText())
Create a custom client side widget which extends VTextField and add the functionality there