定义一个Block

typedef enum {
    XMPPResultTypeLoginSuccess,//登录成功
    XMPPResultTypeLoginFailure,//登录失败
    XMPPResultTypeNetErr//网络不给力
}XMPPResultType;

// 定义一个Block
typedef
void (^XMPPResultBlock)(XMPPResultType type);// XMPP请求结果的block

@interface AppDelegate :
UIResponder <UIApplicationDelegate>

@property (strong,
nonatomic) UIWindow *window;
-(void)xmppUserlogout;
-(void)xmppUserLogin:(XMPPResultBlock)resultBlock;

@end