UIAlertController 基本用法一

1、定义

UIAlertController* alertController =[UIAlertController alertControllerWithTitle:@"提示"message:@"hello"了"preferredStyle:UIAlertControllerStyleAlert];

2、添加action

[alertController addAction:[UIAlertActionactionWithTitle:@"OK" style:UIAlertActionStyleDefault handler:nil]];

3、显示        

[self presentViewController:alertControlleranimated:YES completion:nil];