ios/mac/COCOA系列 -- UIALertVIew 学习笔记

最近在学习ios开发，学习的书籍《ios7 Pragramming cookbook》，做笔记的目的以后方便查看。笔记形式是小例子，将书上的例子书写完整。

UIAlertViewClass 的使用场景

　　1，向用户以一个警告的形式显示信息。

　　 2，让用户确认一些动作

　　 3，让用户输入用户名和密码

　　 4，让用户输入一些文本，这些文本在程序被使用

例1   实现简单显示一些警告信息

新建一个 Single View Application 简单工程，工程名字维AlterView,扩展前缀CB

 

代码如下：

#import "CBViewController.h"

@interface CBViewController ()
@end

@implementation CBViewController

- (void)viewDidLoad
{
    [super viewDidLoad];
    // Do any additional setup after loading the view, typically from a nib.
    UIAlertView *alterView  = [[UIAlertView alloc]
                               initWithTitle:@"学些MAC/IOS开发"
                               message:@"一个UIAlterView的例子"
                               delegate:self
                               cancelButtonTitle:@"取消"
                               otherButtonTitles:@"确定", nil];
    [alterView show] ;
}

- (void)didReceiveMemoryWarning
{
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}

@end

运行结果示意图

例2  让用户输入账号和密码 ，log输出账号和密码

要获得用户点击的是那个按钮可以在 代码实现 UIAlertViewDelegate 代理中下面的方法

// Called when a button is clicked. The view will be automatically dismissed after this call returns

// 用于点击按钮是被调用，返回被调用button的索引

- (void)alertView:(UIAlertView *)alertView clickedButtonAtIndex:(NSInteger)buttonIndex;

#import "CBViewController.h"

@interface CBViewController ()<UIAlertViewDelegate> //添加代理

@end

@implementation CBViewController

- (void)viewDidLoad
{
    [super viewDidLoad];
    // Do any additional setup after loading the view, typically from a nib.

    UIAlertView *alterView  = [[UIAlertView alloc]
                               initWithTitle:@"学些MAC/IOS开发"
                               message:@"请输入你的账号和密码"
                               delegate:self
                               cancelButtonTitle:@"取消"
                               otherButtonTitles:@"确定", nil];
    [alterView setAlertViewStyle:UIAlertViewStyleLoginAndPasswordInput] ;

    UITextField *user = [alterView textFieldAtIndex: ] ;
    user.keyboardType = UIKeyboardTypeAlphabet ;  //设置弹出的键盘样式

    UITextField *pass = [alterView textFieldAtIndex:] ;
    pass.keyboardType = UIKeyboardTypeDefault ;

    [alterView show] ;
}

////实现代理协议的方法
//// 用于点击按钮是被调用，返回被调用button的索引
- (void) alertView:(UIAlertView *)alertView clickedButtonAtIndex:(NSInteger)buttonIndex
{
    //通过返回button索引 得到点击按钮的现实字符串
    NSString *buttonName = [alertView buttonTitleAtIndex:buttonIndex];
    if ([buttonName isEqualToString:@"确定" ]) {
        UITextField *user = [alertView textFieldAtIndex:] ;
        UITextField *pass = [alertView textFieldAtIndex:] ;
        NSLog(@"确定 账号=%@ 密码=%@", user.text, pass.text) ;
    }
    else if ([buttonName isEqualToString:@"取消"])
    {
        NSLog(@"取消");
    }
}

- (void)didReceiveMemoryWarning
{
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}

@end

输出结果

2014-07-09 15:27:05.980 AlertView[8406:60b] 确定账号=goipc 密码=123456

2014-07-09 15:39:31.938 AlertView[8429:60b] 取消

运行的效果图