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robwilson (3) [Avatar] Offline
#1
I've just followed all the steps in the book up to page 74, and comparing my html file to the book shows that I don't have a get:module meta section.

In summary, the main sections I have are...

<script language='javascript' src='org.gwtbook.Dashboard.nocache.js'></script>

<iframe src="javascript:''" id="__gwt_historyFrame" style="width:0;height:0;border:0"></iframe>

The book shows I should have

a meta name gwt:module (no)
a script for gwt.js (no)
history frame (yes)

Could anyone please shed some light on these differences please?

Thanks,
Rob.
robert.hanson (173) [Avatar] Offline
#2
Re: gwt:module not present in default html?
When GWT 1.4 was released, a month or so after the book, the loading mechanism was changed. The <meta> tag and gwt.js file are now the deprecated way of loading a module, although it will still work.

What you see in your HTML page is now the recommended way of loading a module.

There is no difference in semantics between the two ways of loading a module, the new way is just faster.
adam.tacy (269) [Avatar] Offline
#3
Re: gwt:module not present in default html?
...and maybe slightly unfortunately, in printing, the answer Rob gave appears at the top of page 75 rather than on page 74:

"(we cover the GWT loading mechanism in chapter 17—the process just described covers
GWT up to version 1.3, from version 1.4 this gets slightly simpler where only one JavaScript file directly related to your application is loaded, see chapter 17 for details)."

GWT 1.4 was becoming stable as the book was heading to printing so we tried to get as much information known about 1.4 into the book to kept it current whilst not affecting the in process publication steps (i.e. easier to make larger changes to later chapters but only smaller changes to early chapters - you wouldn't imagine how long and how many people are involved in getting a book from written to actually printed!).

If you really want to understand the differences between 1.3 and 1.4 loading I would recommend jumping ahead temporarily to Ch 17 as suggested, in particular 17.2 (The GWT Application Loading Mechanism) and Figure 17.2 on page 565 which shows the differences (in 1.4 a gwt.js file is still produced by the compiler for backwards compatibility, but 1.4's ApplicationCreator creates the structure you are seeing).

Regards,

//Adam
robwilson (3) [Avatar] Offline
#4
Re: gwt:module not present in default html?
Hi Chaps,

Thank you for the rapid response, I kind of thought that might be the case, but I did not want to make any assumptions so early in the book!

Regards,
Rob.