How to check in Vaadin 7 if scrollbar is visible or not for a certain component, for example for Panel
Any implementation of AbstractClientConnector can be extended with AbstractExtension: https://vaadin.com/api/com/vaadin/server/AbstractExtension.html
An extension is a possible way to extend the functionality of your component: https://vaadin.com/docs/-/part/framework/gwt/gwt-extension.html
Adding features to existing components by extending them by inheritance creates a problem when you want to combine such features. For example, one add-on could add spell-check to a TextField, while another could add client-side validation. Combining such add-on features would be difficult if not impossible. You might also want to add a feature to several or even to all components, but extending all of them by inheritance is not really an option. Vaadin includes a component plug-in mechanism for these purposes. Such plug-ins are simply called extensions.
In the client-side extension implementation you can write your custom GWT code like following (pseudo code):
#Override
protected void extend(ServerConnector target) {
// Get the extended widget
final Widget widget = ((ComponentConnector) target).getWidget();
// register RPCs
YourServerRpcImplementation serverRpc = getRpcProxy(YourServerRpcImplementation.class); // client to server
registerRpc(YourClientRpcImplementation.class, this); // server to client, unused in this example
// add listener and update server state
Window.addResizeHandler(new ResizeHandler() {
#Override
public void onResize(ResizeEvent event) {
boolean scrollbarVisible = widget.getElement().getScrollHeight() > widget.getElement().getClientHeight();
serverRpc.yourEventMethod(scrollbarVisible);
}
});
}
Passing events between server and client: https://vaadin.com/docs/-/part/framework/gwt/gwt-rpc.html
Related
I need to add pusher object to vertical layout in Vaadin 13
sources: https://vaadin.com/directory/component/icepush/samples
public class Playboard extends VerticalLayout
{
private ICEPush pusher;
public Playboard() throws ExecutionException, InterruptedException{
generateGUI();
}
private void generateGUI() throws ExecutionException, InterruptedException {
..................
.................
pusher = new ICEPush();
VerticalLayout playboard = new VerticalLayout();
playboard.add(pusher); //Cannot resolve method
...........
............
}
Why would you want to do so? It states at add-on page that
A component that adds push support to Vaadin!
Vaadin(both 7-8 versions as well as Flow 10+, which you are using) has a built-in support for Push currently, so there is no need to use a mentioned add-on. In the simplest case, all you need to do to get push working for your view is to add an annotation. There is a good official documentation on push:
Server Push Configuration
Asynchronous Updates
But,anyway, as mentioned in the previous answer you can't use the add-on with V13,since it's available only for Vaadin 6 and 7
You can't - this is for the so called Vaadin Platform (Vaadin 6-8). You have to find a web component replacement for that feature, write your own, or maybe sometime in the future there will be tooling to retrofit the old components into Vaadin Flow.
In my controller, via service, I get from DB a list of the names of widgets (eg. chart, calendar, etc). Every widget implements WidgetInterface and may need other services as its own dependencies. The list of widgets can be different for each user, so I don't know which widgets / dependencies I will need in my controller. Generally, I put dependencies via DI, using factories, but in this case I don't know dependencies at the time of controller initialization.
I want to avoid using service locator directly in controller. How can I manage that issue? Should I get a list of the names of widgets in controller factory? And depending on widgets list get all dependencies and put them to controller?
Thanks, Tom
Solution
I solved my issue in a way that suggested Kwido and Sven Buis, it means, I built my own Plugin Manager.
Advantages: I do not need use service locator directly in controller and I have clear and extensible way to get different kinds of widgets.
Thank you.
Create your own Manager, like some sort of ServiceManager, for your widgets.
class WidgetManager extends AbstractPluginManager
Take a look at: Samsonik tutorial - pluginManager. So this way you can inject the WidgetManager and only retrieve the widgets from this manager as your function: validatePlugin, checks whether or not the fetched instance is using the WidgetInterface. Keep in mind that you can still call the parent ServiceManager.
Or keep it simple and build a plugin for your controller that maps your widget names to the service. This plugin can then use the serviceLocator/Manager to retrieve your widget(s), whether they're created by factories or invokableFactories. So you dont inject all the widget directly but only fetch them when they're requested. Something realy simplistic:
protected $map = [
// Widget name within the plugin => Name or class to call from the serviceManager
'Charts' => Widget\Charts::class,
];
public function load($name)
{
if (array_key_exists($name, $this->map)) {
return $this->getServiceManager()->get($this->map[$name]);
}
return null;
}
Injecting all the Widgets might be bad for your performance so you might consider something else, as when the list of your widgets grow so will the time to handle your request.
Hope this helped you and pushed you in some direction.
This indeed is a interesting question. You could consider using Plugins for the widgets, which can be loaded on the fly.
Depency injection is a good practise, but sometimes, with dynamic content, impossible to implement.
Another way to do this, is to make your own widget-manager. This manager then can load the specific widgets you need. The widget-manager can be injected into the controller.
Edit:
As you can see above, same idea from #kwido.
I would use a separate service and inject that into the controller.
interface UserWidgetServiceInterface
{
public function __construct(array $widgets);
public function getWidget($name);
}
The controller factory
class MyControllerFactory
{
public function __invoke(ControllerManager $controllerManager, $name, $requestedName)
{
$serviceLocator = $controllerManager->getServiceLocator();
$userWidgetService = $serviceLocator->get('UserWidgetService');
return new MyController($userWidgetService);
}
}
Then the logic to load the widgets would be moved to the UserWidgetServiceFactory.
public function UserWidgetServiceFactory
{
public function __invoke(ServiceManager $serviceLocator, $name, $requestedName)
{
$userId = 123; // Load from somewhere e.g session, auth service.
$widgetNames = $this->getWidgetNames($serviceLocator, $userId);
$widgets = $this->loadWidgets($serviceManager, $widgetNames);
return new UserWidgetService($widgets);
}
public function getWidgetNames(ServiceManager $sm, $userId)
{
return ['foo','bar'];
}
public function loadWidgets(serviceManager $sm, array $widgets)
{
$w = [];
foreach($widgets as $widgetName) {
$w[$widgetName] = $sm->get($widgetName);
}
return $w;
}
}
The call to loadWidgets() would eager load all the widgets; should you wish to optimise this you could register your widgets as LazyServices
How can I change favicon of my pages in Vaadin ? I would like to change favicon of my pages but I have no idea where is the place to change it ? Has somebody experience on it ?
First, create a theme directory: /WebContent/VAADIN/themes/mynewtheme
Then, put your custom favicon.ico in this directory. You also need to set theme property in your application :
public class MyNewApplication extends Application {
#Override
public void init() {
...
...
setTheme("mynewtheme");
}
}
Here is a more detailed version of the similar Answer posted by Greg Ballot. My Answer here relates to Vaadin 7, current as of 7.5.3.
Custom Theme
In Vaadin 7.5, you can drop your favicon graphics image file into your own custom theme. If using the Vaadin plugin for various IDEs (NetBeans, Eclipse) or the Maven archetypes, a custom theme named mytheme should have already been created for you. Drop your image file into that mytheme folder.
The main part of your Vaadin 7 app, your subclass of UI, must specify that it uses your custom theme. Again, if using the IDE plugins and/or Maven archetype, this should have already been configured for you. The easiest way is an Java Annotation on the UI subclass.
#Theme ( "mytheme" ) // Tell Vaadin to apply your custom theme, usually a subclass of the Valo or Reindeer theme.
#Title ( "PowerWrangler" ) // Statically specify the title to appear in web browser window/tab.
#SuppressWarnings ( "serial" ) // If not serializing such as "sticky sessions" and such, disable compiler warnings about serialization.
#Push ( PushMode.AUTOMATIC ) // If using Push technology.
public class MyVaadinUI extends UI
{
…
Favicon Usage/Behavior Not Standard
Remember that favicon behavior is not standardized. Favicons developed haphazardly, mostly out of a sense of fun. The exact behavior depends on the particular browser and particular server. Other than the particular folder location, none of this is special to Vaadin.
Image File Formats
Originally the ICO file format was used exclusively. Since then most browsers have evolved to accept any of several formats including JPEG, TIFF, and PNG.
Image Size/Resolution
Originally favicons were intended to be very small bitmap icons. Some browsers have made various uses of the favicon in situations where you may want to provide a higher-resolution image. But remember that smaller files load faster without keeping your users waiting.
Favicon File Name
Some browsers or servers may handle other file names or name extensions, but I've found it easiest to name my file exactly favicon.ico -- even if using a different format! I usually use a PNG file but name it with the .ico extension. While I cannot guarantee this practice works one every server and browser, I’ve not encountered any problem.
Existing Favicon File
Recent versions of Vaadin have included a Vaadin-related icon in a favicon.ico file in a configured project. So you must replace that file with your own. In Vaadin 7.5.3 the file contains four sizes, the largest looking like this:
Older versions did not add a file, so you drop in your own.
IDE Screen Shots
Here are a pair of screen shots. One is the project (logical) view in NetBeans 8, while the other is a files (physical) view.
In case of custom icon name (Vaadin 7):
public class MyServlet extends VaadinServlet implements SessionInitListener {
#Override
protected void servletInitialized() throws ServletException {
super.servletInitialized();
getService().addSessionInitListener(this);
}
#Override
public void sessionInit(SessionInitEvent event) throws ServiceException {
event.getSession().addBootstrapListener(new BootstrapListener() {
#Override
public void modifyBootstrapPage(BootstrapPageResponse response) {
response.getDocument().head()
.getElementsByAttributeValue("rel", "shortcut icon")
.attr("href", "./VAADIN/themes/mynewtheme/custom.ico");
response.getDocument().head()
.getElementsByAttributeValue("rel", "icon")
.attr("href", "./VAADIN/themes/mynewtheme/custom.ico");
}
#Override
public void modifyBootstrapFragment(BootstrapFragmentResponse response) {
}
});
}
}
EDIT
It is better to use the BootstrapListener as a static nested class: link
Vaadin 23.x (plain spring/war application, no springboot!):
Derive an implementation of com.vaadin.flow.component.page.AppShellConfigurator:
#Theme(value = "mytheme")
#PWA(name = "My application", shortName = "MyApp", iconPath = "icons/favicon.ico" )
public class AppShellConfiguratiorImpl implements AppShellConfigurator {
#Override
public void configurePage(AppShellSettings settings) {
settings.addFavIcon("icon", "icons/favicon.ico", "16x16");
}
}
And put your favicon.ico into src\main\webapp\icons (in order that it is encluded in <war-root>/icons/favicon.ico)
A servlet container (3.0 plus, e.g. Tomcat 8.5) will pick up this class automagically and load it.
I'm doing a project in Vaadin 7.
In my project, I need to disable column reordering feature for particular columns in Treetable?
I'm really searching for function like this 'setColumnReorderIds()'.
Is it possible to do it in Vaadin 7.
Or else I need to write some code with 'ColumnReorderListener()'?
Update
This code is to set the first column fixed in a TreeTable. I want to disable reordering in Hierarchy column in the tree table.
public class CustomTreeTable extends TreeTable {
private static final long serialVersionUID = 1L;
private Object[] visibleColumns;
private KeyMapper<Object> columnIdMap = new KeyMapper<Object>();
#Override
public void paintContent(PaintTarget target) throws PaintException {
super.paintContent(target);
paintColumnOrder(target);
}
private void paintColumnOrder(PaintTarget target) throws PaintException {
visibleColumns = this.getVisibleColumns();
final String[] colorder = new String[visibleColumns.length];
int i = 0;
colorder[i++] = columnIdMap.key("Column 1"); // Logic to keep the first column fixed
for (Object colId : visibleColumns) {
if(!colId.equals("Column 1")) {
colorder[i++] = columnIdMap.key(colId);
}
}
target.addVariable(this, "columnorder", colorder);
}
}
Update 2
I tried what Oskar said..
In addition to
paintColumnOrder(target).
I'm calling
paintVisibleColumnOrder(target),
paintAvailableColumns(target),
paintVisibleColumns(target).
i'm able to stop reordering only for the table headers. But, the body is still reordering. Any guesses on this issue?
In the documentation there is only setColumnReorderingAllowed() which allows to control reordering of all columns. So if your case is to control particular ones it looks to me as a very custom behaviour and I would go with own implementation. Also ColumnReorderEvent is generated after processing the action itself therefore implementing own ColumnReorederListener won't help us here I think.
All actual magic which we want to change happens in private Table.paintColumnOrder() called from public Table.paintContent(), called from public TreeTable.paintContent() (see sources of Table and TreeTable). The solution would be:
extend TreeTable
override paintContent() with merged copies of Table.paintContent() and TreeTable.paintContent()
replace paintColumnOrder() call with your custom logic.
Update
Ok, now I see it's more tricky then I thought at the beginnig, since there is no easy way to access most of required fields and methods after subclassing TreeTable... Moreover, columns are reorered on the client side and only the change event status is sent to inform the server. I don't know how to handle custom reordering without creating custom gwt widget :(
Just started doing some code porting from .Net CF to Blackberry JDE 4.6.1. But haven't found how to implement custom events.
I have a custom syncManager that raise events in .Net CF so I can update the UI (sort of the observer patron).
Any pointers or help where I can start?
I can recommend the j2me-observer project. It has a liberal license and will give you an implementation of the observer pattern which isn't included in J2ME. It can be used to allow UI changes to happen based on fired events.
you can send custom event using.
//you can use any int value for CUSTOM_EVENT
fieldChangeNotify(CUSTOM_EVENT);
and you can handle that event using
public void fieldChanged(Field field, int context) {
if(cotext == CUSTOM_EVENT){
Dialog.alert("custom event");
}
}
I can recommend the open source project javaEventing. It's available at http://code.google.com/p/javaeventing , and makes it easy to define, register for and trigger custom events, much like in C#.
An example:
Class MyEvent extends EventManager.EventObject {}
EventManager.registerEventListener(new EventManager.GenericEventListener(){
public void eventTriggered(Object sender, Event event) {
// <-- The event is triggered, do something.
}
}, new MyEvent());
EventManager.triggerEvent(this, new MyEvent()); // <-- Trigger the event
bob