提示框

    //初始化提示框；
    UIAlertController *alert = [UIAlertController alertControllerWithTitle:@"提示" message:@"按钮被点击了" preferredStyle: UIAlertControllerStyleAlert];
    
    [alert addAction:[UIAlertAction actionWithTitle:@"确定" style:UIAlertActionStyleDefault handler:^(UIAlertAction * _Nonnull action) {
        //点击按钮的响应事件；
    }]];
    
    //弹出提示框；
    [self presentViewController:alert animated:true completion:nil];