I'm using GWT 2.4 with JUnit 4.8.1. When writing my class that extends GWTTestCase, I want to simulate clicking on a button on the page. Currently, in my onModuleLoad method, this button is only a local field ...
public void onModuleLoad() {
final Button submitButton = Button.wrap(Document.get().getElementById(SUBMIT_BUTTON_ID));
...
// Add a handler to send the name to the server
GetHtmlHandler handler = new GetHtmlHandler();
submitButton.addClickHandler(handler);
How do I simulate clicking on this button from the GWTTestCase? Do I have to expose this button as a public member accessor is there a more elegant way to access it? Here is what I have in my test case so far ...
public class GetHtmlTest extends GWTTestCase {
// Entry point class of the GWT application being tested.
private Productplus_gwt productPlusModule;
#Override
public String getModuleName() {
return "com.myco.clearing.productplus.Productplus_gwt";
}
#Before
public void prepareTests() {
productPlusModule = new Productplus_gwt();
productPlusModule.onModuleLoad();
} // setUp
#Test
public void testSuccessEvent() {
// TODO: Simulate clicking on button
} // testSuccessEvent
}
Thanks, - Dave
It can be as easy as buttonElement.click() (or ButtonElement.as(buttonWidget.getElement()).click(), or ButtonElement.as(Document.get().getElementById(SUBMIT_BUTTON_ID)).click())
But remember that a GWTTestCase doesn't run in your own HTML host page, but an empty one, so you'll first have to insert your button within the page before simulating your module's load.
gwt-test-utils seems to be the perfect framework to answer your need. Instead of inheriting from GWTTestCase, extend the gwt-test-utils GwtTest class and implement your click test with the Browser class, like shown in the getting starting guide :
#Test
public void checkClickOnSendMoreThan4chars() {
// Arrange
Browser.fillText(app.nameField, "World");
// Act
Browser.click(app.sendButton);
// Assert
assertTrue(app.dialogBox.isShowing());
assertEquals("", app.errorLabel.getText());
assertEquals("Hello, World!", app.serverResponseLabel.getHTML());
assertEquals("Remote Procedure Call", app.dialogBox.getText());
}
If you want to keep your button private, you'd be able to retrieve it by introspection. But my advice is to make you view's widgets package protected and to write your unit test in the same package so it could access them. It's more convinent and refactoring-friendly.
gwt-test-utils provide introspection convinence. For example, to retrieve the "dialogBox" field which could have been private, you could have do this :
DialogBox dialogBox = GwtReflectionUtils.getPrivateFieldValue(app, "dialogBox");
But note that using GwtReflectionUtils is not mandatory. gwt-test-utils allows you to use ANY java classes in GWT client side tests, without restriction :)
You can do it like this:
YourComposite view = new YourComposite();
RootPanel.get().add(view);
view.getSubmitButton.getElement().<ButtonElement>cast().click();
Related
I have couple of drop downdowns and a download link button. Based on the user selection, i get the file to be downloaded. if the user did not make a selection I show an error on the feedback panel. if the user then makes a selection and clicks on download link it works fine, but the previous feedback message is still visible. How do I clear it.
onclick of the download link, i tried the following, but no use
FeedbackMessages me = Session.get().getFeedbackMessages();
me.clear();
Probably it is
Session.get().cleanupFeedbackMessages()
even it has been changed in Wicket 6.x
I've found this post and I think it is time to share the way for Wicket 6.x and for Wicket 7.x, because Session.get().cleanupFeedbackMessages() was deprecated already.
To do it for Wicket 6.x you have to implement additional filter for the feedback panel. Where to do it, it is your decision to decide.
Create a new FeedbackPanel implementation by extending from the existing FeedBackPanel class
private class MessagesFeedbackPanel extends FeedbackPanel{
private MessageFilter filter = new MessageFilter();
public MessagesFeedbackPanel(String id){
super(id);
setFilter(filter);
}
#Override
protected void onBeforeRender(){
super.onBeforeRender();
// clear old messages
filter.clearMessages();
}
}
Provide a new Filter implementation, by implementing the existing IFeedbackMessageFilter interface
public class MessageFilter implements IFeedbackMessageFilter{
List<FeedbackMessage> messages = new ArrayList<FeedbackMessage>();
public void clearMessages(){
messages.clear();
}
#Override
public boolean accept(FeedbackMessage currentMessage){
for(FeedbackMessage message: messages){
if(message.getMessage().toString().equals(currentMessage.getMessage().toString()))
return false;
}
messages.add(currentMessage);
return true;
}
}
Following code works for me in Wicket 6:
public class MyComponent extends Panel {
...
FeedbackMessages feedback = getFeedbackMessages();
feedback.clear();
I have added some extra functionality to the standard GWT ListBox by extending it like so:
public class FeatureListBox extends ListBox
{
public FeatureListBox()
{
}
public FeatureListBox(boolean isMultipleSelect)
{
super(isMultipleSelect);
}
public FeatureListBox(Element element)
{
super(element);
}
}
Nothing fancy here. However, the Change event is not firing now, or at least the handler (attached per below) is not getting invoked.
FeatureListBox listBox = new FeatureListBox();
listBox.addChangeHandler(new ChangeHandler()
{
public void onChange(ChangeEvent event)
{
// Do something here...
}
});
Any ideas why?
Either remove the no-argument constructor from FeatureListBox or call super() inside it, otherwise the initialization in the superclasses won't happen, which would probably result in what you're seeing.
The problem was in the way I was using my custom list box. In my application I wrap GWT Widgets around existing DOM elements on the page using the static wrap() methods of their widget classes in which the widgets get marked as attached, making them fire events. I didn't do that with my custom list box class originally, so I ended up implementing a static wrap() method similar to the one of the regular ListBox widget and using it in my code. Everything works like a charm now.
I'm trying to use a custom widget: gwtupload with it's custom handlers. The handlers are defined as interfaces, as in, Interface.OnCustomEventHandler and the method, according to the API, that I want to use is like this code, but I'm not sure how to implement this with uiBinder.:
void onCustomEvent (Interface interface)
Normally for uiBinder I use this code for the regular gwt widgets:
#Widget widget;
#UiHandler("widget")
void onClick(ClickEvent event){
//Handle the event processing here.
}
Presently, when I try this,
#UiHandler("widget")
void onCustomEvent(ICustomInterface customInterface){
...
I get this null pointer exception:
[ERROR] Generator 'com.google.gwt.uibinder.rebind.UiBinderGenerator' threw an exception while rebinding '...ViewImpl.ViewImplUiBinder'
java.lang.NullPointerException
Here is the new code I tried:
public class MUpld extends Composite {
private static MUpldUiBinder uiBinder = GWT.create(MUpldUiBinder.class);
interface MUpldUiBinder extends UiBinder<Widget, MUpld> {
}
#UiField MultiUploader uploader;
public MUpld() {
final IUploader.OnFinishUploaderHandler onFinishUploaderHandler = new IUploader.OnFinishUploaderHandler() {
#Override
public void onFinish(IUploader iUploader) {
if (uploader.getStatus() == Status.SUCCESS){
System.out.println("In the onFinish method!");
}
}
};
initWidget(uiBinder.createAndBindUi(this));
uploader.addOnFinishUploadHandler(onFinishUploaderHandler);
}
}
In the debugger, I saw the handler get attached to the uploader widget I defined, but then the current uploader became a different one once the code moved out of this class. I tried using the final modifier, as that is the only way I know to get a variable into an inner class, but gwt would complain with:
[ERROR] com.cdg.complexityCalculator.client.view.MUpld has no default (zero args) constructor.
To fix this, you can define a #UiFactory method on the UiBinder's owner, or annotate a constructor of MUpld with #UiConstructor.
I wasn't able to get either of those options to work, but I realized I had the last two lines of code switched, so I changed it to what I have now and the handler loaded up with the correct object.
Any ideas as to how to get this to work? Everything else is in place, I just need a way to capture this event after my servlet has finished processing.
When I changed the last two lines of code, the handler got loaded properly. Now the objects are being created with the handler binding to the correct object.
initWidget(uiBinder.createAndBindUi(this));
uploader.addOnFinishUploadHandler(onFinishUploaderHandler);
I had to wait until the uiBinder created the instance of the uploader widget, then I was able to add the handler to it.
One of the tricks I've learned is to add a handler in the constructor for a composite widget you create, that way it's more of an encapsulated component. It handles it's own events.
lets say i have a custom widget which has a ClickHandler. Here's the example:
public class TestWidget extends Composite {
private static TestWidgetUiBinder uiBinder = GWT
.create(TestWidgetUiBinder.class);
interface TestWidgetUiBinder extends UiBinder<Widget, TestWidget> {
}
#UiField
Button button;
public TestWidget(String firstName) {
initWidget(uiBinder.createAndBindUi(this));
button.setText(firstName);
}
#UiHandler("button")
void onClick(ClickEvent e) {
Window.alert("Hello!");
}
}
When i try to add this Widget like this:
TestWidget testWidget = new TestWidget("myTestWidget");
RootPanel.get().add(testWidget);
everything is fine. If i click on my button i get the message i expect.
However if i add it like this:
TestWidget testWidget = new TestWidget("myTestWidget");
RootPanel.getBodyElement().appendChild(testWidget.getElement());
my click event is not being fired. I'm struggeling to understand why.
It would be nice if someone could explain this to me or link me to an resource where i can read this up. Finally i would like to know if it is possible to add the clickhandler afterwards i appended the child event and if that way is recommended. Thanks it advance for help.
kuku
When you call add(), Widget.onAttach() is called on the widget that is being added to the panel. onAttach does some work to register the widget to receive events. appendChild() simply attaches one DOM element to another and does nothing else. You should be able to get events working in the second case by doing this:
Element element = testWidget.getElement();
RootPanel.getBodyElement().appendChild(element);
DOM.sinkEvents(element,
Event.getTypeInt(ClickEvent.getType().getName())
| DOM.getEventsSunk(element);
However, I haven't tested this and I wouldn't recommend that you use it in a real application. Using add() is definitely preferred, using appendChild() in this way has no advantages and may lead to unexpected behaviour.
I have a larger application that I'm working with but the GWT History documentation has a simple example that demonstrates the problem. The example is copied for convenience:
public class HistoryTest implements EntryPoint, ValueChangeHandler
{
private Label lbl = new Label();
public void onModuleLoad()
{
Hyperlink link0 = new Hyperlink("link to foo", "foo");
Hyperlink link1 = new Hyperlink("link to bar", "bar");
Hyperlink link2 = new Hyperlink("link to baz", "baz");
String initToken = History.getToken();
if (initToken.length() == 0)
{
History.newItem("baz");
}
// Add widgets to the root panel.
VerticalPanel panel = new VerticalPanel();
panel.add(lbl);
panel.add(link0);
panel.add(link1);
panel.add(link2);
RootPanel.get().add(panel);
History.addValueChangeHandler(this); // Add history listener
History.fireCurrentHistoryState();
}
#Override
public void onValueChange(ValueChangeEvent event)
{
lbl.setText("The current history token is: " + event.getValue());
}
}
The problem is that if you refresh the application, the history stack gets blown away. How do you preserve the history so that if the user refreshes the page, the back button is still useful?
I have just tested it with Firefox and Chrome for my application and page refresh does not clear the history. Which browser do you use? Do you have the
<iframe src="javascript:''" id='__gwt_historyFrame' style='position:absolute;width:0;height:0;border:0'></iframe>
in your HTML?
GWT has catered for this problem by providing the History object. By making a call to it's static method History.newItem("your token"), you will be able to pass a token into your query string.
However you need to be aware that any time there is a history change in a gwt application, the onValueChange(ValueChangeEvent event){} event is fired, and in the method you can call the appropriate pages. Below is a list of steps which i use to solve this problem.
Add a click listener to the object that needs too call a new page. In handling the event add a token to the history.(History.newItem("new_token").
Implement the ValueChangeHandler in the class that implements your EntryPoint.
Add onValueChangeHandler(this) listener to the class that implements the EntryPoint. Ensure that the line is add in the onModuleLoad() method (it is important it is added in this method) of the class that implements the EntryPoint(pretty obvious ha!)
Finally implement onValueChange(ValueChangeEvent event){ //call a new page } method.
That's it