Introduction
I hope it's fairly obvious how to use the main features of this page, especially if you have discovered the little tool tips that pop up when you hold the mouse cursor over a feature. If not, hover your cursor over the GO BACK link above. If a tooltip doesn't appear, don't blame me, your browser isn't up to scratch.
Read on.... (Clicking the little green triangles will take you back to the top of the page) . The screenshot below shows how it should look in IE6 maximised. It may vary with your screen resolution, font settings etc, and some features may have changed since the screenshot was taken - but not much. This is 1024x768 32 bit in WinME on a laptop with small fonts selected. The proportions are different on my desktop PC so don't be surprised if what you have is different again. Note that if you insist on having your favourites or history displays open or have big Windows toolbars taking up valuable screenspace, you can't expect everything to fit neatly as it does here.
What's it all about?
Well, I based this on the Latest Uploads page at Gatwick AvPhotos, which itself developed into a pick-your-own gallery. But there you can only pick how many slides you want in the show and how long they stay on screen. Here there's an extra control to select a pre-programmed gallery. If you want to check out some other category for now go to the database page and select your own, but you can't view them as a slideshow. I may include a d-i-y slideshow category on this page in due course. The page always starts with a welcome photograph on screen: in this case the triple tailfins of Constellation N494TW. To the right of the photo, under the control boxes and buttons are details of the aircraft: the serial or registration number (Regn), the aircraft type and the manufacturer's serial number (msn), sometimes known as the construction number (c/n). The next column is the operator where known. Next come details of the date the currently displayed photograph was taken and the location. Then you may get some notes about markings if these aren't the same as the real serial. There is also a ©opyright reminder - all images in AvPhotosOnline are my own and cannot be re-published in any form without my express permission.
Select a Gallery
The first control is a drop-down box, and the default gallery is "Welcome", which just gets you the single welcome photo. Click the little triangle to the right of the box and a list of the available galleries will drop down. Click the one you want and all being well the first photo in the selected sequence will download. That was easy, wasn't it?
The Slideshow
The button marked AutoSlide will set off a slideshow, but hang on a minute. By default the slides come up in registration order. The number of slides in the sequence is shown in the little text box beside it. You can change this if you want. Reduce it and you'll get less images in the show. Increase it and you'll just mess up the counting since you can't get any more images in the sequence than I've posted! I'll have to fix that. The images cycle around forever until you click another button or change one of the settings. Next choose how many seconds the picture is to stay on screen (after loading) in the second text input box. The default is 5 seconds. Now you can click AutoSlide to start the show. If you have connection problems or your PC has decided to download e-mail or update its virus definitions while you have the slide show running, things may appear to grind to an undignified halt. Well that's because they have! Not much you can do until you have a clear connection again and nothing I can do to prevent it. I have (I hope) squashed a buglet in the programming which allowed the details display to advance even though the images weren't yet loaded from the server. The details now change when the new image starts to load but wait for loading to complete before the slide delay starts. I'd appreciate it if you would report any odd behaviour with this feature, it's more than a bit complicated. The button marked Stop will, unsurprisingly, stop the show. If you change the slide count and timing values while the show is running, it will also stop. It should restart from the current position when you click AutoSlide. If you pick a different gallery everything should reset and you need to click Autoslide once more. If you do nothing at all it will just cycle around until you fall asleep.
Browse photos
You can flip through the album to browse the photos with the Next ( > ), Previous ( < ), First ( << ) and Last ( >> ) buttons. They wrap, so going beyond the last gets you back to the first and going back past the first ends up with the last. Using these keys while the slideshow is running will stop the show. It should restart from the current position if you click AutoSlide.
Home, Help, Info etc
Oh come on, do I really have to tell you that Home gets you to the AvPhotosOnline home page, Help is what got you here in the first place and Info is just the usual "About" box? Other items on the menu bar take you to other pages of the AvPhotosOnline site.
Technical stuff
The whole thing relies on a Microsoft technology called data binding, featured in their Dynamic HTML (DHTML) and for which Internet Explorer versions 4 and above come equipped. Oddly, you need to use a scripting language like JavaScript to get the best out of it - so much for DHTML! IE4 and above come with a built-in database manager - you don't need to buy anything else to maintain simple databases if you know how to use it - and so all the processing is done on your PC, NOT on the server. You just download the data into memory once as a simple text file and IE does the rest with a bit of guidance from your friendly web-page writer. In the case of this page, you don't have to send a message to the server that you want to see the detailed data for the next slide and wait for it come back. Unfortunately you do have to wait for the image file to download! The alternative would be to download all the images before starting the show, which isn't practical considering 20 of them could amount to a megabyte. After the first time round, however, the images should be in your PC's history memory and won't need to be downloaded again on this visit. This way of doing things is something simple souls like me can upload to our websites without having to rely on ISPs and web-hosting companies to provide the technology. What's more it's free! The snag is it won't work with Netscape, older versions of IE or other browsers.
Now you've read that lot, click the triangle below to get back to the top of the page and then take the GO BACK link to return to the galleries.
Michael Hooker, Horley, 13 July 2005.