Basic rules for iPad application development

The iPad also uses the same operating system as the iPhone and can also purchase software through the App Store. Did developers see a new market? If you want to develop software specifically for iPad, please refer to the following iPad development rules.

System Level

◆ Only one program can be run at the same time, and the window is full screen

◆ The program needs to be quickly accessed and exited

◆ For security consideration, the program is executed in the sandbox. Saves Program-related files and settings. You can only use the interfaces provided by the system to communicate with other programs.

◆ Each program runs in its own virtual memory space, but the available virtual memory is limited by the size of the physical memory. That is to say, there is no virtual memory on the disk.

◆ Custom plug-ins and frameworks are not supported.

Program level

◆ (New) The program interface must support any direction. Unlike the iPhone, horizontal and vertical screens are not required at the same time.

◆ The program mainly uses ObjectiveC, but other programming languages can also be used.

◆ All classes supported in iPhone, also supported in iPad

◆ Use the retain/release model for Memory Management

◆ When necessary, the program can start additional threads. However, view-based operations and a large number of graphic operations must be performed in the main program thread.

View Controller

Although the iPad still supports navigation bar and Tab bar, their role is gradually weakened. Because you can create a new view controller called the Split view controller ). For more complex data content, the navigation bar and Tab bar are mainly used to provide support for low-level navigation.

Graphics and multimedia

The iPad supports the same graphics and multi-media libraries as the iPhone. You can play a video in any view without having to play it in full screen.

Event Processing

It is easier to detect gesture events.

Support for device integration

Many features of the iPhone are supported in the iPad. For example:

◆ Accelerator

◆ Location

◆ Map

◆ Settings

◆ Address book

◆ Peripherals

◆ P2p Bluetooth connection

There is no camera in the iPad, but you can use the photo album.

Features of iPad

The screen size is different from that of the iPhone. The iPad is 1024x768.

New classes and interfaces:

◆ Split views.

◆ Pop-up window

◆ You can customize the display style for the content on the covered screen, and set whether to completely overwrite the screen or overwrite a part of the window.

◆ Toolbar can be placed above or below the view

◆ You can customize the input view of a virtual keyboard, which is different from the previous keyboard that was only displayed in the input box on the iPhone. Now you can set a custom input view in any first responder object.

◆ Custom input tools can also be placed on top of the virtual keyboard

Text and display support

◆ Added the Core Text framework.

◆ Custom view to receive keyboard messages

◆ Added the syntax check class UITextChecker.

◆ Supports custom editing of menu class UIMenuController (Note: Previously, it can only be implemented through private APIs)

◆ Added the CATextLayer class for Core Animation to display text.

Supports external display and projection

The iPad can be an external display with a maximum output resolution of 720 p (1280x720 ).

Document Processing support

◆ The application can register and open a specific type of file

◆ UIKit provides the UIDocumentInteractionController class for interaction with unknown files.

◆ Programs with UIFileSharingEnabled key values in Info. plist can share files with users' desktops.

However, note that the iPhone OS does not provide a standard dialog box for opening and closing files, or does not encourage such system-level file operations.

PDF generation

The program can generate PDF documents.