You should not be using su with npm install or bower install.

However, we understand when you see errors such as npm ERR! Error: EACCES, mkdir .., you will relent to using your superadmin power..

GitHub Pages provides FREE hosting of your (static) website.

This post is a guide on hosting your “project” repository with a custom domain.

A good tip for developers using Git is to squash multiple commmits into one.

Why do that?

If you ever work on a task and had multiple commits because you want to be safe and track the changes while work-in-progress, your commit history will be difficult to follow.

It will be hard (and waste of time) for code reviewer, or other developers, to go through multiple commits. There will be bound to be codes that you add, then remove or edit.

Instructions for reinstalling an existing Octopress on a new system, using this website (samwize.com) as an example:

iOS push notification has evolved greatly over the years, from a simple push with a alert string, to the now sophisticated system involving custom actions, localized string and background mode.

Reading the documentations here, here and here… provided clues everywhere on how it works.

This post is to explain what happens when a push reaches a device.

There are times when you have weird Xcode build errors eg. you are absolutely sure that the referenced object is in the project, yet Xcode could not find it.

Or compile errors such as Include of non-modular header inside framework module, when you know the framework works very fine.

You can try clean (Cmd + Shift + K) and build.

But the real way to clean Xcode is to delete folders in ~/Library/Developer/Xcode/DerivedData. Delete folders with your app name, and also ModuleCache. That could well save your day.

When you save a PFObject and encounter the error Found a circular dependency when saving, it could be due to you setting a bidirectional/inverse relationship.

OCMock is a great framework for Objective-C (iOS or Mac OS) for test driven development.

It changes the behaviours of classes during testing.

This is a guide on how to use OCMock, and also raise some of the pitfalls.

Last year, I provided the script to download all PDFs for WWDC 2014.

This year, for WWDC 2015, I have forked ohoachuck’s wwdc-downloader to provide an option to download only the PDFs and sample codes.

To use, download the script and run:

./wwdcVideoPDFGet-curlVersion.sh -p

There is constantly bug with UIActionSheet.

Symptoms: Tapping on the action sheet does not work on the first tap. The subsequent tap works as expected.