Archive for March 18, 2013

Monday, March 18, 2013

Core Data Auto Migration and Sandboxing

P. Taylor Goetz:

Core Data Automatic Migration for NSPersistentDocument requires saving in place, which won’t work in a sandbox-enabled app (even with Read/Write for user selected files).

This is like the more well-known issue with Core Data and SQLite journal files, except that the filename suffix isn’t predictable. Behind the scenes, Core Data tries to create a file with .migrationdestination_ and a long hex string, and the sandbox denies it. This is not some crazy edge case—it’s the default behavior of Cocoa’s basic class for Core Data documents.

A workaround is to put the database file in a package, but this is not always possible. And, in fact, NSPersistentDocument does not support packages.

How to Build an RSS Sync System via

Jens Alfke:

Google pulled the plug on Reader, but you still want a way to keep the news-reader apps on your various devices in sync, so they all know what feeds you’re subscribed to and which articles you’ve already read.

Here’s what you do. I’ve built this before, as part of the OS X Syndication and PubSub frameworks. (It wasn’t identical to what I’m describing here, partly because didn’t exist so I had to do some clever things with hidden file storage on Aren’t you lucky?)

What Lua Scripting Means for Wikimedia and Open Source

Sumana Harihareswara (via Gus Mueller):

So our staffers and volunteers worked on Scribunto (from the Latin for “they shall write”), a MediaWiki extension to allow editors to embed Lua scripts instead of wikitext for templating. And volunteers and Foundation staffers have already started identifying pages that are slow to render and converting the most inefficient templates. We have 488,731 templates on English Wikipedia alone right now. The process of turning many of those into Lua scripts is going to affect everyone who reads our sites — and the Scribunto project has already started giving back to the Lua community.

Safari Still Craps Out Too Frequently

Erik Barzeski:

Seriously, it’s 2013. I have 32 GB of RAM. And Safari still craps out all the time and has to reload every page I’ve loaded with as few as 20 tabs open.

Ever since the Safari Web Content process was split off in Lion and sandboxed (the Safari application remains unsandboxed), I’ve been getting into situations where pages stop responding until I quit and relaunch Safari.

Wolf’s Mother Tries an iPhone

Jonathan Rentzsch:

She mentioned the Clock is wrong. She thought it odd since the other, textual clocks were correct (the first on the Slide to Unlock screen and the uppermost status bar clock). The Calendar app’s date is correct, so she has no reason to believe that the Clock’s icon just happens to be static.


In the same vein, she noted the Weather app must be showing the inside temperature (72°) since it’s currently in the mid-30°s outside when she was looking at it.


She was immediately thwarted when tapping a headline link opened the page in a new tab. Her Google News page was pushed away and the Los Angeles Times’ page came frontmost. Because it was a new page, the back button wasn’t enabled. She was at a loss at how to go back, not noticing the nondescript tabs button that held the key to her return.

Stupid Feed Tricks

Brent Simmons:

Brian is intimately acquainted with the the different ways feeds can be screwed up. So he posted Stupid Feed Tricks on Google Docs.

The difference between theory and practice…

Update (2013-03-18): Brent’s favorite way to screw up a feed.

Checkboxes That Kill Your Product

Alex Limi:

In the currently shipping version, Firefox ships with many options that will render the browser unusable to most people, right in the main settings UI.


What I do want to put the focus on, however, is that you have to perform an audit of your product every so often and see how the people using your product have changed, and what kind of functionality that made sense at the time may not make much sense anymore.

Improving Download Behaviors in Web Browsers

Alex Limi (March 2010):

The aim of this article is to give an introduction to how the most common browsers behave when it comes to downloading files, what opportunities exist, and close with a set of recommendations for how to fix this in Firefox and other browsers. It is my hope that putting these ideas out there will spur some innovation in this area both in Firefox and competing browsers.

Alex Limi (May 2011):

Today, I was very happy to see that Safari has implemented our design in their upcoming release, as evidenced by screenshots posted at Dustin Curtis’ site […]

However, as of Firefox 19.0.2, the Downloads window seems much the same. And, on my Mac, there’s a bug where the Clear List button is always disabled, which drives me crazy. Here’s the plan for Firefox 20.