Calling a Composite's GWT method from another Composite - gwt

I'm new to GWT and trying to make a simple app (like a small version of fmylife). Up to now i made a composite that loads the facts and another composite that has a form to submit new facts (this one has a load method that clear the list and populate again).
I have a button that when you press it, it shows a Window with a form.
That form is used to add new Facts. But I want to refresh the main page when the Fact is added correctly and close this window.
How should I do this? Should I pass some kind of callback to the Window form?
Edit: I didn't express well enough, Window is a DialogBox provided by smartGWT.


Take a look at Events and the Event Bus.
You can also watch this video for a better explanation.


Sure, why not? Pass a callback with some method like onSave to the composite contained in the DialogBox. Design the flow in such a way that the DialogBox composite is always editing the fact model, and it it not be aware of whether it is creating a new fact model or editing an existing one. Let the DialogBox invoke onSave using the callback, when the user submits the popup.
Keep the fact collection data structure CRUD logic out of the DialogBox composite.


You should use DialogBox or PopupPanel instead of opening a new window (most modern browsers opt to open a new tab either way). That way you won't leave the page (that's the whole point of this AJAX thing, right?), you'll just overlay a new Widget over it and then on "submit" it will hide/destroy itself and add a new fact (without reloading the whole page).


Agreed with the DialogBox and PopupPanel solution above. However, if you'd still like to use Window, the following solution comes to mind.
Extend Window and provide hooks to the values you want back. Then, when you create the new CustomWindow, call the addWindowCloseHandler method to get notified when the CusomWindow is being closed. On that event, get the values you need and allow the window to close. Then make an async call to refresh your main page.

Related

can i use fancybox for an online form contact?

I'm creating a contact form, which I want to be pop out (and greyed) and wanted to know if fancybox could be used for this purpose. I currently use it for images but curious to see if it could work for this purpose.

You can use fancy box for a form.
You might have to make some changes to the plugin to get it work though
you can see how to do it here
Based on your comment: There are a few ways to get that done:-)
One way, is to have multiple divs within the form. Make the next button hide one div and show another in the modal. This can be done as many times as you need to do it within the same modal. Then when the form is complete, you can have a submit button now instead of a next or previous button.

Microsoft Access How to refresh the parent form from the subform

I know this question has been ask thousands of time, but I couldn't find a direct answer for this problem.
I am a programmer, but I never bothered learning VBA since this is only a small project I am doing on the side. I would prefer only using macro's.
I currently have a parent form inside a navigation menu, which has a datasheet table which display all the information about all the customers.
http://i.stack.imgur.com/d3TdM.png
In this parent form, I have a button to allow the user to add a new customer which opens a pop up form.
http://i.stack.imgur.com/RDSvq.png
I want the save button in this pop up form to update the parent form onClose. I know the record is working since if I switch off to a different tab and come back to it. I can see the new record added to the table.

Put this on the form frm_addNewCustomer on close event
Private Sub Form_Close()
[Forms]![TheFormYouWantUpdated].Refresh
End Sub

Hyperlink vs Anchor

When to use HyperLink and when to use Anchor?
When using HyperLink how to handle clicks?
com.google.gwt.user.client.ui.Hyperlink.addClickHandler(ClickHandler) is deprecated
com.google.gwt.user.client.ui.Hyperlink.addClickListener(ClickListener) is deprecated as well.
Doc suggests to use Anchor#addClickHandler, but how to use Anchor#addClickHandler when using HyperLink
Does it mean that if I need to handle click I should always use Anchor and never use HyperLink?

Great question, because it is so simple, and yet opens up what might be a whole new area for a lot of GWT programmers. I've up-voted the question just because it can be a great lead-in for people exploring what GWT can do.
Anchor is a widget for storing and displaying a hyperlink -- essentially the <a> tag. Really not much more exciting than that. If you want your page to link to some external site, use anchor.
Links are also used for internal navigation. Let's say I have a GWT app that requires the user to login, so on my first panel I put a login button. When the user clicks it, I would display a new panel with widgets to collect the user's information, code to validate it, and then if validated successfully, reconstruct that first panel the user was on.
Buttons are nice, but this is a browser, and I want my user's experience to be more like a web page, not a desktop app, so I want to use links instead of buttons. Hyperlink does that. The documentation for hyperlink describes it well:
A widget that serves as an "internal" hyperlink. That is, it is a link
to another state of the running application. When clicked, it will
create a new history frame using History.newItem(java.lang.String),
but without reloading the page.
Being a true hyperlink, it is also possible for the user to
"right-click, open link in new window", which will cause the
application to be loaded in a new window at the state specified by the
hyperlink.
That second sentence should help clear it up. The hyperlink is not changing the page in a URL sense (the way anchor does), though the URL will reflect the state of the program by displaying the "token" associated with the hyperlink appended to the base URL after a slash. You define the token. It would be something descriptive like "login" or "help" or "about". But this isn't a new page. There is no additional HTML file you've had to construct to display a help page, for example. It is the state of the current GWT app that is changing. Even if you "open in a new window" you are just running the same app in a particular state.
It looks like a link, but it is really a widget that manipulates the history frame, which in turn allows you to move the state of your GWT application. You don't write a click handler for the hyperlink widget, but a value change handler for the history stack. When you see that the "help" token has been put on the history stack, your handler will execute GWT code to attach to the RootPanel a FlowPanel with embedded HTML text with your help information. This is perceived by the user as a "new page", which is what he expects when he clicks on a hyperlink. The URL will be something.html/help. Now pretend he returns to this URL via the back button, not your hyperlink. No problem. You don't care about the hyperlink click. You only care that, somehow, the history stack changes. Your value change handler fires again, and does the same thing as before to display the help panel. The user still enjoys the experience of navigating through web pages, even though you and I know that there is only one web page and that you are attaching and detaching panels to the RootPanel (or whatever scheme you are using to display your GWT panels).
And this leads to a bonus topic.
This bonus is a bit more complicated, but ironically, it could help better understand hyperlinks. I say more complicated, but really, it helps solidify this notion that a GWT application is made up of a series of states, and that the web page on the screen is just the user's perception of those state changes. And that is Activities and Places. Activities and Places abstracts away this history frame manipulation, handling it in the background once you've set up a mapper with a GWT-provided class designed for this purpose, allowing you to break down your app into a series of activities, and as the user interacts through these activities he is put into different places, and each place has a view. Moreover, the user can move from place to place using browser controls like the address bar, bookmarks, history, and the backward/forward buttons, giving the user a real web-like experience. If you really want to get a grip on the conceptual difference between hyperlinks and anchors, you should try to learn this GWT topic. It can really make you change the way you see your apps, and for the better.

Hyperlink (or InlineHyperlink) is basically no more than a kind of Anchor with a ClickHandler that calls History.newItem and preventDefault() the event (so that the link is not actually followed).
Actually, Hyperlink won't do that if it thinks (and yes, it's only a guess) you right-clicked or middle-clicked (or ctrl-clicked) on the link (depending on the browser), to open the link in a new window or tab.
If you need any other behavior, then don't use Hyperlink and use Anchor instead. And if you want to add some behavior to an Hyperlink, then use an Anchor and mimic what the Hyperlink does. And you can reuse the HyperlinkImpl to have the right-click/ctrl-click handling (see links below).
But actually, if you need something that looks like a link and do something on click, but does not have a "target URL" (i.e. it shouldn't be right-clicked/ctrl-clicked to open in a new window/tab, or it wouldn't mean anything to do so), then do not use either an ANchor or Hyperlink, use a Label of whatever instead, and make it look like a link (but well, maybe you should use a Button and have it look like a button then; Google used to have link-alike buttons –such as the "refresh" link/button in GMail– and changed them to look like buttons when they really aren't links).
See also https://groups.google.com/d/msg/google-web-toolkit/P7vwRztO6bA/wTshqYs6NM0J and https://groups.google.com/d/msg/google-web-toolkit/CzOvgVsOfTo/IBNaG631-2QJ

Wicket: Form in a modal window

I have written an panel which supports file / image uploads. So the panel is a simple plain form. The panel works in a normal Wicket page.
What I would like to do now:
I would like to use the panel in a modal window. The panel is displayed correctly. However, when I submit it / upload a new file, my browser prompts whether or not I would like to leave the page. The page which contains the DIV of the modal window is a form itself.
My research didn't turn up any interesting information about forms in a modal window expect it has to be self contained (nested form). I think this prerequisit is met.
Is there any information available, what I have done wrong? Any tutorials?

You need to use an AjaxSubmitButton (or AjaxSubmitLink) to submit your form. The problem is that the modal window requires Ajax communication. If you use the window to just reprocess a whole page and don't care about the Ajax'ness, then you can override the ModalWindow#getCloseJavaScript() method.

As Martijn pointed out, the modal window relies on AJAX communication. So use AjaxSubmitButton or equivalents. When components in the main window need to be updated after the submit of the modal window, this can be done by adding them to the AjaxRequestTarget.
However when it comes to multi part forms (file uploads) this does not work quite. Apparently multi part doesn't play nicely with AJAX. One has to do an IFrame trick as pointed out e.g. here: http://www.dooriented.com/blog/2008/04/23/wicket-ajax-like-file-upload-on-a-modal-window/

Editing Records with MVVM/MVVM-Light

I have created a very simple wpf app with mvvm light.
I have rows in a list view, these are templated representations of Book objects.
I can click a row, then click an edit button, this button loads a new window and sends the new window the book to edit (using mvvm-light's Messenger).
The issue I have is when I edit the record in my new window the data on the main form is updated. The text boxes are bound to the object received via the Messenger.
I know this is because I have essentially passed a reference to the same Book object around the place, therefore I update in one place.. and voilà it updates on the main page too.
What I would like to know is.. is there a standard way/method/concept to achieve what I am trying to do? i.e. create an "edit" page/screen with the option of discarding the edits?
thanks.

Could you make your entity implement ICloneable and create a clone for editing?