I need to find and monitor all the photos on a hard drive or a folder for a photo organizer. Currently I'm doing this naively: recursively traversing, manually marking folders as indexed, and repeating that process to catch when photos are added or moved.
The problem is with a large enough folder tree this is very expensive, so I'm looking for tips to do this differently and/or tips on keeping it a low cpu process.
Ideally solutions would be not platform-dependent.
EDIT: I'm using xulrunner currently, but could compile a module do platform specific stuff.
What about the first run? Is there no solution (even platform-dependent) besides running through the entire folder tree manually.
Ideally solutions would be not platform-dependant.
Impossible. The Win32API has FindFirstChangeNotification, Linux has inotify (and others), Mac OS X has FSEvents, et cetera. This is stuff that's very low-level, and no OS does it the same as any other OS. If you want something cross-platform, you have to find an API with several backends that works on the platforms you want, but if there are any of these, I haven't yet found them.
I don't know of a way to do this in a platform independant way, but on Linux I'd hook into inotify to call something when a file gets added or updated. You could even use inotify-tools to run a script when that happens, so you don't have to be running all the time to capture all these events if they're infrequent. Just have the script update the database, and optionally notify your gallery/display program if it's running.
Are you coding on .NET? If so, you could use the FileSystemWatcher class instead.
Why not user a filewatcher program, which will notify you of changes in particular folder trees?
If you want to write your own you could use the FileSystemWatcher class to do it.
One answer as of 2014 is facebook's watchman: https://facebook.github.io/watchman/
A couple of years ago I ported some functions of Windows API to Linux like (FindFirstChangeNotification, FindCloseChangeNotification ...) it has some limitations but for what you need it could be enough, please take a look at: https://github.com/paulorb/FileMonitor
Related
I just wanted to get clarification on the approach I'm taking with my program. I'm making a program with custom interface for achiving folders. I would like to use 7zip if possible. In the past I have written batch scripts to that use 7zip command line for archiving. If I want to use my VB tool on a system that doesn't have this available, I would like for this to be embedded in my app.
My question is that know how to embed an exe in a VB app, but does this make it immediately available for use in the program no matter where I use it? Or it make the exe available to be deployed somewhere on the station, then I would have to call it from the disk and then possibly delete it when I'm done?
I've done some searching online for similar applications, but am still unsure of how to use embedded files. I'm not looking for example code. Just clarification on whether I can immediately call the exe from within my app, or I embedding just means I can place that file somewhere on the station that I move my app to and then use it? Clarification on this would be most welcome. Thanks!!!
I’m new to Qt Quick. So, This might sound like a dumb question. But I’m struggling with this.
I want to develop a complete UI for my embedded system using Qt Quick. So, I need QML to run my system.
Now, which library to install on my target embedded linux system.
I ‘ve seen this page : http://qt-project.org/downloads but it shows the library with 228MB! which will float my system size abnormally. I expect my system to be around 50MB only! I think this comes with lot of things which I may not want.
I may use qml, for internet browsing purpose parts of webkit (webkit module for qtquick)
xml.
So, Can you please help me which to install? & how??
Thanks & Regards
inblueswithu
Check http://qt-project.org/doc/qt-4.8/qt-embedded-install.html for a initial documentation.
Please note, that this will install everything, meaning all Qt modules. You might be able to strip some of them away, also you might now need all image plugins. However, as a start this should work for you.
With the tools we have today for assets optimization (for example YUI compressor), how do you automatize it?
For example, I have designed a new website using LESS, so every time I have to edit CSS I have to manually convert them to LESS. The same for Javascript.
So I have to make my PHP project to point to my uncompressed CSS/JS, and when I'm finished, I compress/optimize them, and point my project to the optimized ones again.
I know that there are tools that helps with this (like less.app, which I've used), and that even there are PHP libs that manage all this problem (like Assetic), but I don't like them much. I'm searching for a "programmed" way to deal with optimized assets. Maybe some script that "watches" the uncompressed files or something...
I wish I could have too many alternatives as the Django framework has.
Please, if the question is not well redacted, tell me and we can improve it, so we can establish a good practice for assets :)
I think one efficient solution would be to do this task on the development side, when writting code, and point the code to the optimized files.
One tool that seems to work well is Live Reload (only for OS X, although there is a Windows version on the way).
I like this option as there is no overload on the code to maintain assets.
My program may have several top-level windows open at a time, and I need to send a particular message to all of them (a notification of a change). I know how to do it using the Win32 API, but this is a cross-platform program using wxWidgets. I can't seem to find anything in the wxWidgets documentation about this, but that may simply be because I don't know what to look for.
I can solve this by having each of the top-level windows register itself with the wxApp object when it's created, but that's a manual process that I'm likely to forget on occasion, so I'd rather avoid it if possible. Does anyone know of an existing solution?
There is a global variable wxTopLevelWindows that is a list of the top level windows. See this wxWidgets Discussion Forum thread
I need to build a fairly simple app but it needs to work on both PC and Mac.
It also needs to be redistributable on a disc or usb drive as a standalone desktop app.
Initially I thought AIR would be perfect for this (it ticks all the API requirements), but the difficulty is making it distributable, as the app would require the AIR runtime to be installed to run.
I came across Shu Player as an option as it seems to be able to package the AIR runtime with the app and do a (silent?) install.
However this seems to break the T&C from Adobe (as outlined here) so I'm not sure about the legality.
Another option could be Zinc but I haven't tested it so I'm not sure how well it'll fit the bill.
What would you recommend or suggest I check out?
Any suggestion much appreciated
EDIT:
There's a few more discussions on mono usage (though no real conclusion):
Here and Here
EDIT2:
Titanium could also fit the bill maybe, will check it out.
Any more comments from anyone?
EDIT3 (one year on): It's actually been almost a year since I posted that question but it seems some people still come across it every now and then, and even contribute an answer, even a year later.
Thought I'd update the question a bit. I did not get around to try the tcl/tk option at the end, time constraint and the uncertainty of the compatibility to different os versions led me to discard that as an option.
I did try Titanium for a bit but though the first impressions were ok, they really are pushing the mobile platform more than anything, and imho, the desktop implementation suffers a bit from that lack of attention. There are also some report of problems with some visual studio runtime on some OSs (can't remember the details now though).. So discarded that too.
I ended up going with XULRunner. The two major appeals were:
Firefox seems to work out of the box on most OS version, so I took it as good faith that a XULRunner app would likely be compatible with most system. Saved me a lot of testing and it turned out that it did run really well on all platforms, there hasn't been a single report of not being able to start the app
It's Javascript baby! Language learning curve was minimal. The main thing to work out is what the additional xpcom interfaces are and how to query them.
On the down side:
I thought troubleshooting errors was a sometimes difficult task, the venkman debugger is kinda clunky, ended up using the console more than anything.
The sqlite interface is a great asset for a desktop app but I often struggled to find relevant error infos when something didn't work - maybe i was doing it wrong.
It took a little while to work out how to package the app as a standalone app for both PC and Mac. The final approach was to have a "shell" mac app and a shell pc app and a couple of "compile" script that would copy the shells and add the custom source code onto it in the correct location.
One last potential issue for some, due to the nature of xulrunner apps, your source code will be deployed with the app, you can use obfuscation if you want but that's something to keep in mind if you want to protect your intellectual property
All in all, great platform for a cross-platform app. I'd highly recommend it.
Tcl/Tk has one of the best packaging solutions out there. You can easily wrap a cross-platform application (implemented in a fully working virtual filesystem) with a platform-specific binary to get a single file executable for just about any modern desktop system. Search google for the terms starkit, starpack and tclkit. Such wrapped binaries are tiny in comparison to many executables these days.
Many deride Tk as being "old" or "immature" but it's one of the oldest, most stable toolkits out there. It uses native widgets when such widgets exist.
One significant drawback of Tcl/Tk, however, is that it lacks any sort of printing support. If your application needs to print you'll have to be a bit creative. There are platform-specific solutions, and the ability to generate postscript documents, and libraries to create pdfs, but it takes a little extra effort.
Java is probably your best bet, although not all Windows PCs will necessarily have Java (most should). JavaFX is new enough you can't count on it - you'll probably find a lot of machines running Java 1.5 or (shudder) 1.4. I believe recent Mac OS still ships with 1.5 (latest version may have changed to 1.6).
Consider JavaFX
It would run everywhere with a modern JRE ..!
AIR could be an option, but only if you don't mind distributing two different files (the offline runtime installer and your app), and expecting the user to run one and then the other. You do have to submit an online form at Adobe's site saying you agree to distribute the offline installer as-is, rather than digging out individual DLLs or whatever, before they give you the installer.
Unfortunately there's currently no way to get both an AIR app and the runtime to install from one file though. I'm not sure what the deal with Shu is, or whether it's doing anything that isn't kosher.
i would recommended zink. it has all the functionalities you require for desktop. however, the las time i used it it was a bit glitchy.
i was hung up by trying to write a 6M file to the disk. thought it trough and changed the code to write 512K chunks at a time (3min work, fast).
probably it still has some little annoying glitches like making you think on root lvl but the ease of use and the features are just way too sweet to ignore.