Web Info & Tutorials

Nous avons présentement deux belles portées de teckel clean vie de superbe cooperation et de couleur recherchée Vaccinée vermifugée avec carnet de santé et garantie Contactez-nous il

Yahoo is holding a free all day developer workshop at their headquarters in Sunnyvale, CA on September 29th, followed by a 24 hour hack-through-the night event.

We’ll kick things off on Friday, September 29th with a free all-day developer workshop. Then we’ll launch a 24-hour Hack Day with an outdoor party into the wee hours, with special guests providing the soundtrack. (Details to come later, but we guarantee this won’t be your usual corporate-wedding-band leading the crowd through 2am group sing-alongs of “Brick House.”) We’ll hack through the night, keep going through Saturday morning, and wind it all up that evening with hacker demos, judging from a panel of luminaries. and special awards for the coolest hacks. We’ll have special guest speakers all weekend, with Michael Arrington of TechCrunch presiding over the festivities. And after nightfall we’ll close things out with another round of entertainment that you would be happy to pay for, except that you won’t have to.

I’m a little too old to enjoy hacking through the night (it’s good to see the term “hacking” rescued from its conflation with “cracking,” though), but I’m sure lots of young and serious developers will attend.

So why are Yahoo! and Google, through its Summer of Code, wooing developers? For the same reasons that Microsoft and other software companies have been wooing developers for decades: to find prospective employees and build a qualified labor pool; to drive adoption of their platform at companies by influencing their IT staff; to encourage development of third party applications based on their platform and services.

This may be restating the obvious, but this event is one more sign that both Yahoo! and Google view themselves as software companies every bit as real and legitimate as Microsoft.

Scott Guthrie has written up a tip for Enabling Back/Forward-Button Support for ASP.NET AJAX UpdatePanel.

For example, the below code could be written by a developer in response to a selection change within a list to to add the previous list selection to the browser's history via Nikhil's "HistoryControl":

private void ContentList_SelectedIndexChanged(object sender, EventArgs e) {
   history.AddEntry(contentList.SelectedIndex.ToString();
}
 

Once you add entries into the history control, the back/forward button will be enabled in the browser. Nikhil's history control then exposes a "Navigate" event which fires when you press the forward or back button in the browser, and this event then exposes the identifier entry provided before when the view was added into the browser history. You can then use this to restore the page to whatever state it should be in to match the previous history item and update the page:

private void HistoryControl_Navigate(object sender, HistoryEventArgs e) {

    int selectedIndex = 0;

    if (String.IsNullOrEmpty(e.Identifier) == false) {
        selectedIndex = Int32.Parse(e.Identifier);
    }

    // Update the content being displayed in the page
    contentList.SelectedIndex = selectedIndex;

    // Mark the update panels as needing an update
    mainUpdatePanel.Update();
}
 

Download the code for Nikhil's history control and start using it here

According to Harry Fuecks in this post on the SitePoint PHP blog, using Ajax should be easier:

The Catch 22 of AJAX is, for the sake of an easy life, most of the time we want to write “synchronous code” but asynchronous is the only way to avoid some rather nasty usability issues. This means rather than being able to write simple code, as we’d like to. We’re required instead to handle this via callbacks, but that’s now introduced a whole load more potential issues.

These issues he mentions include requiring a global XMLHttpRequest object to be available and handling multiple calls to a javascript function (like if the user gets a little too impatient). To help combat these issues, Harry recommends a two projects out there that have the functionality to make life a little bit simpler:

• Narrative Javascript
• jwacs (Javascript With Advanced Continuation Support)