The proxy method of UIApplicationDelegate, uiapplication

The proxy method of UIApplicationDelegate, uiapplication

UIApplication

UIApplication-> UIResponder

1. Introduction
1> the whole application symbolizes that an application is a UIApplication object and uses the singleton design mode.
2> access this singleton object through [UIApplication sharedApplication]

2. Common usage
1> set the red number in the upper-right corner of the icon
App. applicationIconBadgeNumber = 10;

2> set the style of the status bar
App. statusBarStyle = UIStatusBarStyleBlackOpaque;

3> display and hide the status bar
App. statusBarHidden = YES;

4> display the circle above the status bar
App. networkActivityIndicatorVisible = YES;

5> open external resources
* Open a webpage
[App openURL: [NSURL URLWithString: @ "http://www.baidu.com"];

* Call
[App openURL: [NSURL URLWithString: @ "tel: // 10086"];

* Text message
[App openURL: [NSURL URLWithString: @ "sms: // 10086"];

6> proxy properties (when some system-level events occur in the application, the agent will be notified and handed over to the agent for processing)
@ Property (nonatomic, assign) id <UIApplicationDelegate> delegate;