If you use dataTaskWithURL , your intention might be getting a data from server and display the data to your UI. But, sometimes it makes a problem that the resulted data is nil. To solve this issue, first of all…
In iOS the default transition between presenting view controller and presented view controller is .CoverVertical. But sometimes you might want to change it to a different animation style. If you setup a presented view controller , it has a property…
I felt difficult to understand the relationship between AnchorPoint and Position in Layer. So I found this in stackoverflow. And it helped me a lot to understand it. Through my testing I got some principle. If a layer’s frame is…
When you draw a circle by using core animation , you might use CAShapeLayer and UIBezierPath to draw it. UIBezierPath(arcCenter: view.center, radius: view.bounds.width / 2, startAngle: startAngle, endAngle: endAngle, clockwise: true).CGPath The code above there are startAngle and endAngle parameters…
I like to post an article to wordpress through Byword or Ulysses. And those tools use wordpress’s xmlrpc.php. By the way if you use xmlrpc.php with your own server , you might face up to infinite attacks which target xmlrpc.php.…
Sometimes I am a little irrated by making the statusbar white in iOS development. It looks simple. But, the way to do it is a little complicated. How to make your status bar style white in iOS9 Put the code…
Recently I needed to extract a data from Apple’s HealthKit. They provide various queries in HealthKit framework. But it didns’t meet my intention. So I started to use NSString substring function to extract the data. But, it wasn’t good to…
NSBatchUpdateRequest allows that you can directly store and modify your records rather than with an object graph. By the way it seems that it doesn’t support updating or modifying a relationship in a core data. If you want to learn…
In iOS development you can put a padding into a UITextField with a code below. First of all , you can create a customized UITextField class for giving it an inset . And then you can put a code below…
When people see Keynote at first, mostly they are impressed by Keynote’s fantastic animation effects. I did that, too. But, you have to be careful before you use an animation, because an animation which doesn’t have a clear reason to…