Is there a way I can write a mac os app that gets notified when there's a new file of a certain file type (lets say a .jpg file) created somewhere on the system?
Does finder maybe have some mechanics in place that gets notified about new files that I can pull from?
The thing I want to achieve is an app that whenever the user creates a file of a certain file type asks the user if she wants to upload it or share it etc.
Also interested if, and if so, how it's possible to achieve this in Windows.
Yes, this is possible using the File System Events API, FSEvents:
https://developer.apple.com/library/content/documentation/Darwin/Conceptual/FSEvents_ProgGuide/UsingtheFSEventsFramework/UsingtheFSEventsFramework.html
Related
I have the following need to implement on Windows: file with files.
Originally I was thinking to use directory with extension. Something like "folderA.myappext", so when user clicks on it in Explorer, my app is launched instead of folder being opened. Unfortunately, I was unable to find a way to do that. Then I tried to use Alternate Data Streams. This works just fine, but several problems with it:
It works only in NTFS, so no way to send it via email or FTP as is;
Only WinRAR can properly archive it, and you still have to do extra clicks in the UI for that;
The real file size (with all streams in it) is not shown in Explorer and does not participate in showing free/used space, which can very quickly lead to big problems for the user.
No, I can't use zip or any other way to combine files into one - this is high-performance app that also requires write streaming (i.e. it changes data all the time).
Any idea how else to achieve my need on Windows? I know on MacOS you can use 'package', but there is nothing like that on Windows. Any idea?
Something like "folderA.myappext", so when user clicks on it in Explorer, my app is launched instead of folder being opened.
You can't do it based on the extension because folders don't have extensions but you can do it with desktop.ini. Windows 7 and later supports custom verbs on folders.
A working example can be found here.
I am having issues with my "Automatically Add to iTunes". As a result, I am trying to make an Applescript that will be stored on my USB, and when I click on a certain Music File, I want it to launch an applescript.
I did some research, and everyone keeps telling me about Launchd. How would I use this command to run an applescript saved as .app? I want to store this Music File and the Applescript on my USB, because I have multiple computers. Can I get it to run as soon as I open a specified music file? Thank you.
I eventually figured out a way to do what I wanted, which was to somehow play a music file from inside the application. All I did was use the idea of resources because it can reference itself without having to rely on a file stored somewhere else on the system. Here's a link to essentially what I did: https://apple.stackexchange.com/questions/157724/applescript-path-to-files-in-applications-resources
in short, I contained the music file within the app itself and played it when it was needed.
I am distributing my OS X application on individual USBs and, for this reason, everything must be self contained.
The app itself lets users input information and then saves this information to an existing text file (specifically an ObjectDB database). Herein is my problem.
I'd like to keep this text file inside the app itself (i.e. inside the Content folder) so it's out of the way and can't be deleted by the average user. But once the app is signed, it seems the text file can't be altered with any new information without getting flagged by Gatekeeper. Is this really the case? There's no way to store data files within apps now?
I'd appreciate any suggestions. Thanks.
Yes, you are correct. If you modify the application package, the signed package is no longer valid. That's kind of the purpose of signing a package.
Your options are to store the text file in a temporary folder on the user's computer, or to instruct your users to disable gatekeeper (don't do this).
My application downloads a PDF and stores it in the LocalState folder for my Windows 8 app.
I have a link within the app that I would like to show the PDF when the user clicks it.
I've tried displaying it using ms-appdata:///local/pdfs/filename.pdf in a window.open call and I also tried using the InAppBrowser plugin within cordova with no luck. Additionally, I've tried the following:
var uri = new Windows.Foundation.Uri('ms-appdata:///local/pdfs/filename.pdf');
var file = Windows.Storage.StorageFile.getFileFromApplicationUriAsync(uri);
Windows.System.Launcher.launchFileAsync(file).done();
I know the file exists as I'm getting a file result back. Just not sure how to allow the user to view it.
By design, the local appdata folder on Windows is accessible only to that app, or to full-trust desktop applications (and this is probably true of similar sandboxed locations on other platforms). As a result, a Windows Store app that gets launched with Launcher.launchFileAsync won't be able access that location (nor can a webview process, which is also sandboxed). If a desktop application gets launched, on the other hand, it probably can access the file, but you can't tell ahead of time if that's the case. Bottom line is that local appdata isn't a good location for letting other apps get at the file.
You'll need to save the file in another location that is accessible to other apps. There are two approaches here, both of which will require a little user interaction to select a location, so they can place the PDFs anywhere they want:
Have the user select a save folder for your app, which they can do once. You would invoke the FolderPicker for this purpose, and save the selected folder in the FutureAccessList. This way you can have the user select the save folder, which grants you consent to save there, and by saving it in the FutureAccessList you can retrieve it in subsequent sessions without having to ask the user again. Refer to the File Picker Sample and the File Access Sample for more.
Have the user select a save location for each individual file, using the FilePicker (see the same sample), and you can also use the access cache to save permissions to those individual locations if you need them later.
There might be Cordova plugins that work with these APIs too, but I haven't checked. Either way, once the file is in an accessible location, launching the file should work just fine.
As an alternate solution, you could consider rendering the PDFs directly in your app. Windows has an API for this in Windows.Data.Pdf, with an associated sample. There might be a plugin or other JS libraries that could also work for this.
I have a Cocoa app "PDFHistory" on Mac OS X that uses the NSDocument architecture to save and load PDF files that are internally formatted specially for my app. I want to make it so whenever I save a file (e.g., "mydoc.pdf") from PDFHistory, then subsequently double-clicking on mydoc.pdf will automatically open it in PDFHistory.app. However, I don't want to make it so all .pdf files are automatically opened in PDFHistory, but rather use the system default (probably Preview.app). The .pdf suffix is a requirement, though, since I need the user to be able to e-mail the files to other users who can view the file in their default PDF viewer.
The problem is that if I set the LSHandlerRank to "Owner", then all .pdf files will be opened with PDFHistory, which is bad (since I only understand the internals of the .pdf file that PDFHistory wrote out). But if I set LSHandlerRank to "Alternate", then all .pdf files will be opened to the system default app (Preview.app), which is confusing for the user who had just created the file using my app.
Once upon a time, "creator codes" could be used to implement this sort of capability, but launch services started ignoring them back in Snow Leopard (see http://tidbits.com/article/10537). UTIs are not a substitute that provide this capability (see http://boredzo.org/blog/archives/2009-09-22/how-not-to-use-utis).
Using Finder to get info on the file allows the user to specify a specific app to use to open the specific file. This supposedly works by setting a "usro" property in a the file's resource. There is some open-source code to mimic this behavior (https://github.com/AlanQuatermain/SetAppAffinity), but is uses deprecated functions, and so would cause Apple to reject the app from the App Store. Similarly, people have posted AppleScript to set this property (https://discussions.apple.com/thread/2597365), but sandboxing would prevent me from invoking it.
Although the .pdf suffix is a requirement in order to be able to send the files to users on other systems/platforms, I considered trying to have the suffix registered with two extensions as ".phistory.pdf", which would allow "file.phistory.pdf" to be opened in PDFHistory, but "file.pdf" would be opened in the default PDF viewer. However, this simply didn't work: it appears that the final suffix is the only one used by launch services, and everything before that is ignored.
So is there any way to have my app be the default app for opening files that it created itself?