Great writing, terrible reading

Apple has recently released Xcode 4—a major part of this release is an overhaul of the user interface. Change in your development environment is always a bit disruptive, but overall I think the move towards a single-window environment that adapts to different working modes is a good thing.

But this post is not to debate these changes to the programming environment. Rather, I’d like to discuss the new documentation viewer and how it has become unsuitable for both Mac and iOS development.

Apple’s technical documentation has always been top-notch: well written with just the right amount of technical detail. Unfortunately, the documentation viewer that we use to read this valuable information has been declining in ease of use over the past few releases.

It has gotten to the point where frustration with usability overshadows the excellent content. The best way to describe these annoyances is by example: I often get the feeling that the writers who create this prose don’t understand how we use it. Hopefully, this critique will help Apple create a viewer that’s just as good as the information it holds.

A corrupt index

A developer coming from Xcode 3 will have a terrible first experience with the new documentation viewer. Any previously installed documentation sets are incompatible with Xcode 4. Methods that you know exist just don’t show up:

Search in vain

There are also problems with the Jump Bar navigation stack not being recorded correctly and the browsing history being unavailable (the back button isn’t available when it should be.)

Presumably, there is a corrupt or incompatible index. The workaround is to delete and re-install the documentation set, but this is far from obvious.

Since I currently have three different versions of Xcode installed (and will continue to use Xcode 3 for the foreseeable future), I’m wondering if this corrupted/incompatible index will continue to be a problem. Fingers are crossed, but at least now we know what to fix if it breaks.

Popup hell

When you hold down the option key and click on a symbol in Xcode, you see the following window:

Popup hell

For novices, this window has some utility—it provides a simple way for them to dig into what is probably unfamiliar territory (“What’s a UIWindow anyway?”).

The problem is that this window becomes a roadblock for experienced developers. We know damn well what a UIWindow is: we need to dig into the details of this important class. Maybe we want to know more about the rootViewController instance or look at some of the methods in UIResponder (because we know it inherits from that.) This helpful popup quickly becomes a hindrance.

In previous versions of Xcode, holding down the shift key along with the option key gave you a quick way to avoid this popup help. In Xcode 4, that shortcut is gone.

Considering that this feature can get in the way hundreds of times per day, this is truly popup hell.


No methods

Once you get the documentation index in working order and actually make it past the popup help, your next hurdle is to locate the information you seek. Let’s say we’re looking for some background on what happens when a new -rootViewController instance is assigned. We’ve got the page of documentation, but there aren’t any controls to show the methods for the UIWindow class:

No methods

Besides being a pain in the butt, this is wholly inconsistent with the behavior in the code editor:


(Note that typing “ro” is enough to select “rootViewController” in the code editor’s popup menu. That, followed by the enter key gets you to the code of interest.)

From a developer’s point-of-view, the header files and the documentation page go hand-in-hand. Make the UI affordances the same and we don’t have to think about whether we’re looking at code or the words that describe it.

With a little more digging, you’ll find that you can get to the rootViewController documentation with the Jump Bar. Unfortunately, it takes a lot more effort than in the code editor: you have to click on the class name, and then move the mouse until the subcategories appear. Choose “Instance Methods” and wonder why rootViewController isn’t there. Then move the mouse back and try Properties.

Bingo (but you don’t feel like a winner.) And forget about navigating these lists quickly and easily with the keyboard as you can with the code editor.


Unmanaged complexity

Our final navigation problem is reading chapter-based documentation. These are the crown jewels of Apple’s developer documentation. Titles like The Objective-C Programming Language, iPhone Human Interface Guidelines, and the Cocoa Fundamentals Guide are essential reading for all developers, both beginner and advanced. As I began learning about Xcode 4, of course I turned to the excellent User Guide.

These guides typically span many chapters when sections that cover a wide range of topics. And this is how you navigate through those chapters:

Unmanaged complexity

Managing complexity, indeed.

The pity here is that someone in developer documentation has forgotten that a Table of Contents tells a much more important story than the individual chapters. A roadmap lets you visit the destinations efficiently.

To get an idea of how painful this is, try finding the recommended Singleton implementation in the Cocoa Fundamentals Guide using the Jump Bar. I’ll wait. (For extra credit, count how many menus you open in the process.)

Of course the documentation viewer has a search function, but even that’s a bit laborious because you have to click on a lot of disclosure triangles to find the right item in the results. Why aren’t the relevant results opened automatically? (And, yes, option clicking the disclosure triangle can be used to achieve this goal, but the question still remains: why isn’t this the default action?)

Updated March 29th, 2011: Matt Neuburg has discovered that for some documents, search results don’t show where your term occurs; you’re shown a higher-level page, but not the actual page.

The root of the problem here and with the method names in the class documentation, is that a deep hierarchy is too hard to navigate. Present the information in a single list and it becomes much more useful. Imagine how bad the code editor navigation would be if it presented a hierarchy based upon classes, properties and methods. It’s flattened into a single menu for a reason: and those same reasons exist in the documentation viewer.

The Jump Bar is a great addition to Xcode, but it’s true power lies in having a predictable end point. With code, that end point is a function, property or method. With documentation, that end point is elusive: it varies depending both with the type and the structure of the documentation you’re viewing. And that’s a real problem when you’re looking for something.


ePub, not PDF

While we’re on the subject of this long-form documentation, why isn’t more of it available in the ePub format used by iBooks? It’s pretty safe to assume a huge majority of Mac and iOS developers have an iPad and like to use it for technical documentation. Searching for “Apple Developer Publications” in iBooks results in only six books. That’s a great start, but there is still a lot of documentation available only in PDF.

PDF is, of course, an option for iBooks. But turns out to be unsuitable because there is no back button. If you click a link in the PDF file, it’s a one way proposition. And for technical documentation, that’s a deal killer.

ePub also has the advantage of better font control and image viewing.


Some good news

Fortunately, it’s not all bad news. This new version of the documentation viewer seems to keep track of its place on the page much more reliably than in the past. Gone are the days where hitting the back button put you back as the top of the page (instead of the method or property you were looking at previously.)

This one simple fix will save developers a huge amount of time. Thanks!


This situation with the Xcode document viewer has gotten so bad two developers, Alex Gordon and Jean-Nicolas Jolivet, have taken matters into their own hands. This ultimate workaround is an application called Ingredients.

Ingredients parses the HTML files used by Apple’s own viewer and persists the information with Core Data. The result is quick access to the documentation you need with advanced options to filter and sort to your liking. Recent work by Troy Gaul added an item to the Services menu so a keyboard shortcut can be created to view the selected symbol from any text editor (include Xcode.)

If the problems mentioned above affect you adversely, take a look at this alternative documentation viewer. And please take a moment and file duplicate bug reports using the Radar links above. This is the best way to give Apple an idea of how much this is affecting our daily work. Thanks!

Updated March 22nd, 2011: The developers of Ingredients are now accepting donations.

Twitterrific firsts

Why are third parties important in the Twitter ecosystem?

Let Twitterrific count the ways:

  1. First use of “tweet” to describe an update (see page 86 of Dom Sagolla’s book.)
  2. First use of a bird icon.
  3. First native client on Macintosh.
  4. First character counter as you type.
  5. First to support replies and conversations (in collaboration with Twitter engineering.)
  6. First native client on iPhone.

And more.

Updated January 19th, 2023:

7. First app to leave the App Store.

Mac App Store guide

It’s no secret that the Mac App Store is a terrific new distribution channel for developers. Apple also provides plenty of documentation on how to prepare your app for submission.

Unfortunately, there’s not much information on how to create a product that can also be distributed through more traditional channels, such as your own product website. This guide will help you update your Xcode projects to make it as simple as possible to create products for both channels simultaneously.


The basic strategy is to create two build targets: one that creates everything for your own website, and another that creates the stuff Apple requires for the Mac App Store. The examples were all written using Xcode 3, but can be adapted to newer versions as needed.

The build target for your own website will include the Sparkle framework for doing updates. The one for the Mac App Store will create signed code that does a cryptographic check of the license receipt.

Note that these techniques can be used even if you’re only doing distribution on the Mac App Store: beta testers will benefit from builds that don’t require a receipt before launching.

To take you through the entire process, I’m going to use a real world example: I originally wrote these instructions while preparing our Flare product for release. When you see “Flare”, think “MyApp”. Likewise, “Iconfactory” will be “MyCompany.”

Certificate Setup

Before setting things up, make sure that you have two certificates in your keychain:

3rd Party Mac Developer Installer: The Iconfactory
3rd Party Mac Developer Application: The Iconfactory

If you don’t already have these installed, you can get them from the Developer Certificate Utility in the Member Center on the Apple Developer website.

Project Settings

In Project Build Settings, under Packaging, enable Info.plist preprocessing with:

Info.plist Other Preprocessor Flags: -C
Preprocess Info.plist File: Checked

Do this for both the Debug and Release configurations.

Why do you want to preprocess your Info.plist file? Because there are subtle differences between the settings required for the Mac App Store and your own website. You could, of course, solve the problem by having two Info.plist files, but then you run the risk of them getting out of sync: what happens when you change the version number in one file and forget to do it in the other? Keeping things like document types consistent is tedious work: it’s much easier to configure your app with a single file.

Since things like checking license files and expiration dates are a pain when you’re debugging code, we’ll also define a DEBUG flag in the Debug configuration:

Other C Flags: -DDEBUG

Target Settings

You’ll want to create two build targets:

Flare App

It’s likely that you already have one target and can just duplicate it. The target “Flare” will be for your website, while “Flare App” is destined for the Mac App Store.

Make sure that both targets are using the same Info.plist source file for both the Debug and Release configurations:

Info.plist File: Flare-Info.plist

When you duplicate a target, Xcode “helpfully” creates a new Info.plist file for you. Since you’re going to be using a single file that’s customized using the preprocessor, you don’t need this second file and can delete it from the project folder.

It’s also important to remember that any new files that get added to the project now must be added to both targets. The goal is to keep both of them in sync.


In the target’s Link Binary With Libraries build phase, make sure that Sparkle.framework is included. If you’re following these steps just so you can have a beta build, leave this framework out.

Flare App

In Flare App’s Link Binary With Libraries build phase, make sure that Sparkle.framework is not included. You’ll want to make sure that IOKit.framework and Security.framework are included in the list (since they are used to determine the MAC address and check certificates during license verification.)

While you’re at it, make sure that Sparkle.framework is not in the target’s Copy Files build phase. Even if your app is not linking to Sparkle, a rejection awaits if the App Review team finds the framework in the application bundle.

Since we’re going to be adding code that checks which version is being built, add a new preprocessor flag to both the Debug and Release configurations for the target:

Other C Flags: -DMAC_APP_STORE

In your Objectve-C source code, you can now do things like this:

	BOOL validLicense = AppStoreLicenseCheck();
	BOOL validLicense = MySuperSekretLicenseCheck();

App Store submissions must use signed code, so you’ll need set the following build setting in the Code Signing section:

Code Signing Identity: 3rd Party Mac Developer Application: The Iconfactory

You may also want to do this for the Flare target as well.

In the Linking section, you need to add the OpenSSL cryptographic library so the App Store license can be checked:

Other Linker Flags: -lcrypto

Do this for both the Release and Debug configurations since you’ll want to use Apple’s test_receipt while debugging your license verification code.

Finally, in the Target Build Settings, add the following under Packaging:

Info.plist Preprocessor Definitions: MAC_APP_STORE


Now you can update your Info.plist to work with preprocessor definitions. For example, the Flare-Info.plist is:

#define BUILD_VERSION 1.0
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "">
<plist version="1.0">
	<string>Copyright © 2006-2011 The Iconfactory & Artis Software</string>

Note that after adding the preprocessor definitions, the file will no longer open as a property list. You’ll need to right-click on the item in the Groups & Files list and select Open As > Source Code File.

The MAC_APP_STORE preprocessor definition allows a different bundle identifier to be selected, forces 10.6.6 as a minimum OS version, and removes the Sparkle configuration information.

Distribution Targets

It’s now time to automate the build of these two targets. This will be done with two aggregate build targets. Create the following:


The first will be used for your own website and the second is for the App Store.

For both build targets, make sure to define the following build setting for the release configuration:


This value gets used in the run scripts to generate file names.


The first thing in the “Distribution_Iconfactory” target should be “Flare”. After that, create a new run script build phase (right-click on “Distribution_Iconfactory” and select Add > New Build Phase > New Run Script Build Phase. Name it “Package Release”.

This script will create several things:

  • A ZIP file with build results. A version number is also added to the file name.
  • A signature for the file that Sparkle will use to verify a new update.
  • An appcast file that can be uploaded to your website.

The contents of the run script are as follows:

set -o errexit

[ $CONFIGURATION = Release ] || { echo Distribution target requires "'Release'" build configuration; false; }

VERSION=$(defaults read "$BUILT_PRODUCTS_DIR/$" CFBundleVersion)

PACKAGE_NAME=`echo "$PRODUCT_NAME" | sed "s/ /_/"`

rm -f "$PRODUCT_NAME"*.zip
ditto -ck --keepParent "$" "$ARCHIVE_FILENAME"

SIZE=$(stat -f %z "$ARCHIVE_FILENAME")
PUBDATE=$(LC_TIME=en_US date +"%a, %d %b %G %T %z")

PRIVATE_KEY=$(security find-generic-password -g -s "$KEYCHAIN_PRIVKEY_NAME" 2>&1 1>/dev/null | /usr/bin/perl -pe '($_) = /"(.+)"/; s/\\012/\n/g' | /usr/bin/perl -MXML::LibXML -e 'print XML::LibXML->new()->parse_file("-")->findvalue(q(//string[preceding-sibling::key[1] = "NOTE"]))')
echo "$PRIVATE_KEY" > /tmp/sparkle.key

[ -n "$PRIVATE_KEY" ] || { echo Unable to load signing private key with name "'$KEYCHAIN_PRIVKEY_NAME'" from keychain; false; }

SIGNATURE=$(openssl dgst -sha1 -binary < "$ARCHIVE_FILENAME" | openssl dgst -dss1 -sign /tmp/sparkle.key | openssl enc -base64)

echo $SIGNATURE > /tmp/sig.out

rm /tmp/sparkle.key

[ -n "$SIGNATURE" ] || { echo Unable to create signature for "'$ARCHIVE_FILENAME'"; false; }

cat > "$BUILT_PRODUCTS_DIR/appcast.xml" <<EOF
<?xml version="1.0" encoding="utf-8"?>
<rss version="2.0" xmlns:sparkle=""  xmlns:dc="">
    <title>Flare Release</title>
    <description>Most recent version of Flare.</description>
      <title>Version $VERSION</title>

(Thanks to Marc Liyange for the original idea.)

Before this script will work, you need to create a secure note in your Keychain named “Sparkle Private Key”. Contents should be the “DSA PRIVATE KEY” text from the dsa_priv.pem file you created when setting up Sparkle.


The first thing in this aggregate target is “Flare App”. After that build step, add this run script build phase. Name it “Package Release”:

set -o errexit

[ $CONFIGURATION = Release ] || { echo Distribution target requires "'Release'" build configuration; false; }

VERSION=$(defaults read "$BUILT_PRODUCTS_DIR/$" CFBundleVersion)

PACKAGE_NAME=`echo "$PRODUCT_NAME" | sed "s/ /_/"`

rm -f "$PACKAGE_NAME"*.pkg
productbuild --component "$" /Applications \
	--sign "3rd Party Mac Developer Installer: The Iconfactory" "$ARCHIVE_FILENAME"

This script produces a .pkg installer file that’s signed with the Iconfactory’s certificate.

Distribution Build Script

Since both of the distribution builds create a binary in your Project’s build/Release folder, you need to remember to clean the target before building. To make this easy, just create the following shell script named “build_release”:


current_tools=`xcode-select -print-path`

if [ $current_tools != $build_tools ]; then

if [ $switch -ne 0 ]; then
	echo "Switching from $current_tools to $build_tools..."
	sudo xcode-select -switch $build_tools
	echo "Using $build_tools..."


xcodebuild \
	-configuration "$configuration" \
	-target "$target" \
	clean build

xcodebuild \
	-configuration "$configuration" \
	-target "$target" \
	clean build

if [ $switch -ne 0 ]; then
	echo "Restoring $current_tools..."
	sudo xcode-select -switch $current_tools

This script also ensures that you’re building with a released version of the Xcode developer tools (installed in /Developer). This is important if you do iOS development, as you’re likely to have a beta versions installed as well.

Changes to App Delegate

So far, we’ve been focused on building and packaging your release. You’ll also need to change your source code to accommodate the distribution channel.

If you haven’t done so already, make sure that there are no Sparkle objects in your MainMenu.xib file (as is suggested by the documentation.) The reason for this is simple: the App Review team does a grep for SUUpdater on binaries are submitted. If you have an archived object in the NIB file you’ll be rejected.

Since you’ll still need an SUUpdater object, you’ll need to create an instance of the object manually as you awake from the NIB. Since the application delegate is also on the responder chain, it can also handle the -checkForUpdates: message:

#import "Sparkle/SUUpdater.h"

- (void)awakeFromNib
	[[checkForUpdatesMenuItem menu] removeItem:checkForUpdatesMenuItem];
	[[SUUpdater alloc] init];

- (IBAction)checkForUpdates:(id)sender
	[[SUUpdater sharedUpdater] checkForUpdates:sender];

You’ll also need to create a NIB outlet for the “Check for Updates…” menu item so that it can be removed from the Mac App Store version.

(If you have your own purchasing and registration menu items, you can handle them in a similar manner. I can guarantee you won’t get through App Review with a menu item titled “Purchase Flare…”.)

There are two different bundle identifiers for a single application named “Flare” (one for the version from the website and another for the Mac App Store). A user could get confused if they have both copies installed (especially if one of them is a trial version with limited functionality.) To help users with multiple versions, you should add the following code at launch to check if the one from the web site is installed alongside another from the App Store:

- (void)applicationDidFinishLaunching:(NSNotification *)aNotification
#ifndef DEBUG
	// check that a trial version isn't installed
	NSWorkspace *workspace = [NSWorkspace sharedWorkspace];
	NSString *pathToAppStoreVersion = [workspace absolutePathForAppBundleWithIdentifier:@"com.artissoftware.flare"];
	if (pathToAppStoreVersion) {
		NSString *message = [NSString stringWithFormat:@"It looks like you have a copy of Flare from the Mac App Store installed in \"%@\".\n\nThe application you just launched is a trial version and should be removed. Would you like to quit now so you can move this unneeded file to the Trash?\n\nHint: Use the \"Move to Trash\" item in the \"File\" menu after the Finder window appears.", [pathToAppStoreVersion stringByDeletingLastPathComponent]];

		NSInteger result = [[NSAlert alertWithMessageText:@"Multiple Copies Installed" defaultButton:@"Quit and Reveal in Finder" alternateButton:@"Continue" otherButton:nil informativeTextWithFormat:message] runModal];
		if (result == NSAlertDefaultReturn) {
			[workspace selectFile:[[NSBundle mainBundle] bundlePath] inFileViewerRootedAtPath:nil];


If you’re using these techniques to build a beta version in parallel with your Mac App Store build, you’ll want to have some expiration checking code in the app. Otherwise, your final beta will find its way onto the Internet…

// expiration is used for any (beta) builds that aren't for the Mac App Store

- (void)checkExpiration
	NSDate *today = [NSDate date];
	// pick the date to expire on
	NSDate *expireDate = [NSDate dateWithString:@"2011-04-01 00:00:00 -0800"];
	NSDateFormatter *dateFormatter = [[[NSDateFormatter alloc] init]  autorelease];
	[dateFormatter setDateFormat:@"h:mm a 'on' EEEE',' MMMM d',' yyyy"];
 	NSString *expireDateString = [dateFormatter stringFromDate:expireDate];

	if (! [[today laterDate:expireDate] isEqualToDate:expireDate]) {
		[[NSAlert alertWithMessageText:@"Take Five Beta" defaultButton:@"OK" alternateButton:nil otherButton:nil informativeTextWithFormat:@"This beta release of Take Five expired at %@.", expireDateString] runModal];
		[[NSApplication sharedApplication] terminate:self];
	else {
		[[NSAlert alertWithMessageText:@"Take Five Beta" defaultButton:@"OK" alternateButton:nil otherButton:nil informativeTextWithFormat:@"This release of Take Five is a beta and will expire at %@.", expireDateString] runModal];

- (void)applicationDidFinishLaunching:(NSNotification *)aNotification
#ifndef DEBUG
	[self checkExpiration];

Changes to main.m

The license check for the Mac App Store should happen as early as possible in the app. It’s recommended that this happens before NSApplicationMain is called:

#import "ValidateReceipt.h"

int main(int argc, char *argv[])
	NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init];
	if (! validReceipt()) {
		pool = (NSAutoreleasePool *)1;
	[pool drain];

	return NSApplicationMain(argc, (const char **) argv);

The code that assigns an invalid value to the pool object is done as a simple protection against piracy. If someone tries to patch the exit(173), they’ll just be met with an objc_msgSend exception when the pool is drained.

Of course, you’ll want to add additional code that checks the validity of the receipt elsewhere in your code. The Apple Developer website has additional information on how to validate your store receipts.

Receipt Validation

As far as validating the license is concerned, the bulk of the code to parse and validate the receipt can be gotten from the ValidateStoreReceipt project on github. You’ll need to change the hard-coded bundle identifier, version numbers and paths used in the project as you adapt this code for your own product.


You’ll also want to sign code sign the app you distribute outside of the Mac App Store. Apple has a helpful guide on how to make your app compatible with Gatekeeper.

To quickly check that your build is signed correctly with a Developer ID, you can use the spctl command and make sure it is “accepted”:

$ spctl -a -v accepted
source=Developer ID


There’s a lot going on here, so you’ll certainly want to test both the distribution builds. The builds that are going to beta testers or onto your own website are straightforward: it’s just a ZIP file that can be loaded onto the target system. Once loaded, check that menu item for Sparkle updates is present. You’ll also want to check the Package Contents to see that the correct bundle identifier is set.

Things get a little more complicated when you start testing the build for the Mac App Store.

Start by reading Apple’s instructions on testing the installation process. Unfortunately, these instructions only show you how to get the application installed in your /Applications folder:

$ sudo installer -store -pkg Flare-1.0.pkg -target /

The documentation fails to mention that the installation process can fail if duplicate copies of the app are present elsewhere on the system (e.g. in the build folder.) Beta versions that use the same bundle identifier can also be a problem.

Apple’s test documentation also fails to mention that sandbox users accounts can be created in iTunes Connect (under Manage Users.) These user names and passwords can then be entered after launching the installed application and a receipt will be generated in the application’s _MASReceipt folder.

In order for this launch test to work, the app metadata must be defined in iTunes Connect (a binary does not need to be uploaded, it only needs to show up in “Manage Your Apps”.) Also make sure you sign out and quit the App Store app before launching your app to test the receipt processing code.

A bug report has been filed.


Hopefully these long-winded instructions will be helpful as you prepare your release for the Mac App Store. We’ve already used them several times for our own products, so I’m guessing they will be. :-)