c# read syslistview32 items tooltips via winapi

Question

i want to write an application, which reads under windows xp the quick launch items in the order like they are located in the taskbar, and sets hotkeys for each of these item. windows + 1 should start the first application windows + 2 the second, etc. (like in windows 7)

all of these items are found i a folder, but if i read the items of this folder, i dont get the right order of these items.

i found two solutions the get the right order - first:

in the registry an entry is found, where its saved how they are located, but not in plain text. i dont know how to read this, and cant reverse engine it.

the second: read via winapi the items tooltip from the taskbar, so i can (if there are not items with the same name) search via the name in the quick launch folder. the quick launch bar is just a listview (syslistview32). via sendmessage i got it work to count the items, and start one (faking a click on this item), but how the hell can i read the tooltip? i have googled a lot, tried everything, but i didnt get it run.

i hope you have any snippets for me, to solve this problem.

cheers

Answer 1

Determining the order of the items in the Quick Launch toolbar programmatically is going to be inherently fragile. There's not an API exposed for this, which means that it's subject to change in future versions of Windows, breaking your code that relied on assumptions about undocumented implementation details.

However, this is less of a problem in this specific case than it normally would be, since the Quick Launch toolbar doesn't exist anymore (or, at least, no one uses it anymore). The last version of Windows that used the Quick Launch toolbar was Vista, so if you make sure that your code is compatible with Vista and earlier, you should be fine. It won't work with newer versions anyway.

The positions of items in the Quick Launch toolbar is stored in the Registry in the following key:

HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\Streams\Desktop

You can extract the information from there, parse and interpret it, and then use it as you like. As you mention, this information isn't stored in plain text form because that would be very slow for the shell to load and parse itself. Since this is undocumented and not designed to be used by clients, they had no particular benefit in making it user (or developer) friendly. All that matters is what's most efficient for the shell, and storing the binary information from its internal structures is the obvious choice.

You will need to reverse engineer this in order for it to be useful to you. The way I'd go about it is probably by setting up a test environment with a couple of items in the Quick Launch bar in a particular order, exporting the information from the Registry, moving one of the items around, exporting the updated information from the Registry, and comparing the two exported Registry files to see what changed. Rinse and repeat as many times as necessary to deduce the pattern. (Really makes you wonder why so many developers actually do take the time to reverse-engineer undocumented aspects of Windows, doesn't it?)

The other option would be to use Spy++ to investigate the windows that implement the taskbar and its Quick Launch toolbar. I don't have a pre-Windows 7 system around, but it sounds like from the question that you've already done this and determined that the Quick Launch toolbar is implemented using a standard ListView. If you know the name of that window (and the names of its ancestor windows), you can walk through those windows to obtain a handle to the window you're interested in. And then you can determine the order of the items in the window as if it were a standard ListView in your own application.

The documentation for ListView controls is here; that should get you started in the right direction. You can get the text of one of the subitems by sending the LVM_GETITEMTEXT message.

This is probably the easier way of doing it. The same caveats apply--there is nothing keeping future versions of Windows from changing the names of those windows or the way that the taskbar is implemented, but since the only versions of Windows that have a Quick Launch toolbar have already been released (and therefore aren't likely to change), this may not be a big problem.

Then again, with the fact of the Quick Launch toolbar's obsolescence in mind, I struggle to comprehend why this endeavor is even worthy of investing developer time.

Also, even once you get this program all written and installed, consider what happens when the user adds a new item to the Quick Launch toolbar or re-arranges the existing items. How is your utility going to know that and adjust the keyboard shortcuts accordingly? What if an installer adds/removes an item from the Quick Launch toolbar?