IOS

If the IOS App uses CoreData and has database updates (new tables, fields, and other operations) in the previous version, it is necessary to migrate the CoreData database when overwriting the installation program, the procedure is as follows: 1.

For details about NSJSONSerialization, the official documents include: You use the NSJSONSerialization class to convert JSON to Foundation objects and convert Foundation objects to JSON. an object that may be converted to JSON must have the

Recently encountered a problem in the project. On the setting page, there are two input boxes. When you want to press the box, the date control is displayed, and you can select the date and time. Baidu once and finds that there is no complete

In XCode 4.2 (with LLVM): In-(void) release {}, the warning: Semantic Issue is displayed: conflicting distributed object modifiers on return type in implementation of 'release' to remove the warning, modify the following:-(oneway void) release {}

[Cpp]01. # import 02.03. @ interface TestGestureRecognizerViewController: UIViewController {04. UIView * aView;05 .}06. @ property (nonatomic, retain) IBOutlet UIView * aView;07. @ end08.09. //////////////////////////////////////// //////////////////

[Java] /* print numbers in the code */NSLog (@ "------------------ resultBlocks -------------------->"); int (^ resultBlocks) (int) = ^ (int num) {return num * 20;}; int resultNum = resultBlocks (2); NSLog (@ "result: % 4d", resultNum ); NSLog (@

Using the Protocol to delegate tasks is a process that declares certain methods and attributes and stores them in the Entity document. The Protocol is like some norms, and the classes of practice protocols must comply with these norms. Create the

1. preface in Android, views are often converted to Bitmap. For example, screenshots are taken and images are generated for the entire screen View; coverflow needs to convert a page-by-page view to Bitmap to achieve complex graphic effects (shadows,

There are design patterns in software design, and design patterns in uidesign. Because table views are widely used in iOS, This section describes two uidesign modes in table views: Paging mode and Pull-to-Refresh mode. These two models have become

I just created a function to shake the iOS device and trigger some experience. Now I searched the internet and read the development documentation. I feel that there are too many bad articles on the Internet, there are also a lot of articles that are

In iOS development, you need to interact with the WEB server, such as displaying a batch of data from the web service on a table. The Data Interaction format is XML, and the protocol used is SOAP. The requested data contains images. Generally, the

The client uses the iPhone application, and the screen is relatively simple. Click the send button to send some strings to the server. Click the receive button to read some strings from the server and display them on the screen.   The UI section of

UILabel * label = [[UILabel alloc] init]; NSString * text = @ "hellohellohellohellohellohellohellohellohellohellohellohellohello"; label. text = text; [label setNumberOfLines: 0]; UIFont * font = [UIFont fontWithName: @ "Arial" size: 14]; // set the

[Html]   What is ARC? ARC is a new feature launched by iOS 5, which is called Automation Reference Counting ). Simply put, retain/release is automatically added to the Code. The Code that was manually added to handle the reference count of memory

1 PrefaceWhen some content needs to be displayed on the screen, but the screen size cannot provide the required area, we need to consider using the UIScrollView control. 2. code exampleZYViewController. h:   [Plain] # import  @ Interface

Recently, someone asked me when to use self. assignment. I summarized it and sent it for your reference. Please make an axe if you have any questions. 　　 When self .. is used is actually related to the access method of Obj-c, but many people have

AVAudioPlayer is the most basic audio player class in AVFoundation. framework. It is similar to MPMediaPlayerController in some basic operation functions, such as play, pause, and volume. The difference is that AVAudioPlayer does not have a queue.

1. string constants NSString * s = @ "test "; NSLog (@ "s: % lx", [s retainCount]); // ffffffffffffff (UINT_MAX (Maximum value an 'unsigned int ')) Because "test" is a String constant, the system does not reclaim it and does not reference it for

1 Preface Create a UIRotationGestureRecognizer monitor and bind it to your view to capture the gesture that the user uses his fingers to rotate on the screen. The UIRotationGestureRecognizer class has a rotation attribute, which can be used to set

1 PrefaceThe CGContextSetShadow process is used to apply a shadow to the shape drawn in the graphic environment. CGContextSetShadowWithColor process: the parameters accepted in this process are identical to those of CGContextSetShadow, but a