UIApplication的一些属性

1. iPhone不进入锁屏待机状态：

[UIApplication
sharedApplication].idleTimerDisabled =
YES;
如果希望能进入待机锁屏状态，设置为NO就可以了。

2.设置icon上的数字图标：

[UIApplication
sharedApplication].applicationIconBadgeNumber
= 4;

在iOS8.0以后在使用这个属性之前必须先设置

[[UIApplication
sharedApplication] registerUserNotificationSettings:];

3.设置摇动手势的时候，是否支持redo，undo操作

[UIApplication
sharedApplication].applicationSupportsShakeToEdit =
YES;

4.判断程序运行状态

if ([UIApplication
sharedApplication].applicationState ==
UIApplicationStateActive) {

}

typedef
NS_ENUM(NSInteger, UIApplicationState) {
    UIApplicationStateActive,
    UIApplicationStateInactive,
    UIApplicationStateBackground

} NS_ENUM_AVAILABLE_IOS(4_0);

5.显示联网状态

[UIApplication
sharedApplication].networkActivityIndicatorVisible =
YES;

6.打开一个网页：

[[UIApplication
sharedApplication] openURL:[NSURL
URLWithString:@"http://www.baidu.com"]];

7.发送电子邮件

NSString *recipients =@"mailto:first@example.com?cc=second@example.com,third@example.com&subject=Hello from California!";

    NSString *body =@"&body=It is raining in sunny California!";
   
NSString *email = [NSString
stringWithFormat:@"%@%@", recipients, body];

    email = [email stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding];

    [[UIApplication
sharedApplication]openURL:[NSURL
URLWithString:email]];

8.拨打电话：

[[UIApplication
sharedApplication] openURL:[NSURL
URLWithString:@"tel://1234567890"]];

9.发送短信:

[[UIApplication
sharedApplication] openURL:[NSURL
URLWithString:@"sms://1234567890"]];