Users of The Archive and Dropbox have reported issues with deleting files in their Dropbox-managed folders in the past weeks: the app would beachball forever. Apparently, Dropbox’s recent migration from ~/Dropbox to ~/Library/CloudStorage affects this. I had the occasional Google Drive user in the past months report similar issues but couldn’t make much sense of it – until now.
I’ve enabled using the macOS system trash in Emacs to feel safer experimenting with dired and other file manipulation functions in Emacs. This enables using the trash by default: When this is enabled, move-file-to-trash is used to delete files. The manual reveals what’s affected, but only the function API docs from within Emacs tell the whole story (and are super hard to search online for whatever reason):
All previous installments in this series were written some time during the past 6 weeks or so. I couldn’t spend a lot of consecutive time on eitherthe coding problem or the posts, so it became a pain to keep up with all the details and experiments – I hope I have nevertheless told a somewhat intelligible story so far.
NSDocument’s save panel comes prepared with a file format picker that contains the app’s registered document types. This is a very nice convenience, but when you run into trouble with the default picker, as I did, you wonder if writing your own from scratch would be easier.
When I researched what caused TableFlip to lose permissions to write out files, I learned about “related items” in the Sandbox. A good example from the docs is to open a movie file plus its subtitle captions together. The user would select the movie in an NSOpenPanel. This usually grants access to the movie file directly per Sandboxing restrictions. You can declare the subtitles file to be a related item so that the Sandbox allows you to read both. That’s clever.
Users have reported problems with TableFlip saving their files recently. One wrote about it in the Zettelkasten forums, if you want to see the problem in context. To reproduce the problem: when you open foo.txt in TableFlip and a text editor, then change the file in the editor rapidly, TableFlip would show a “You don’t have permissions” error once you tried to save changes from TableFlip later.
I found the Foundation way to check for file existence very roundabout. It returns 1 boolean to indicate existence and you can have another boolean indicate if the item is a directory – passed by reference, like you used to in Objective-C land. That’s a silent cry for an enum. So I created a simple wrapper that tells me what to expect at a given URL:
Let’s say you write a plain text editor that can work with multiple text files at a time. As a backbone for processing information, you use ReSwift to model the data flow in a clean fashion. The user has 10 files open, changes the text in 1 file’s tab. The user leaves the text field and your awesome autosaving is triggered.