ios UI设计与开发 弹出式视图

1.Alert View 一般给用户提供告警信息。

 如： 

UIAlertView *alert =[[UIAlertView alloc] initWithTitle:nil message:@"相机不能用" delegate:nil cancelButtonTitle:@"关闭" otherButtonTitles:nil];
        [alert show];
        [alert release];

2.Action Sheets用来提示用户在可能的几种操纵中作出选择，也可以用来在用户将要进行不可逆的危险操作时，给用户确认或取消的机会。

    创建Action Sheets 需要3个步骤：

1.指定相应的ViewController遵循UIActionSheetDelegate协议

2.实现相应的delegation方法

3.创建并显示Action Sheet是给用户选项，所以按钮数目肯定要大于一个。另外，按钮上显示的文字应该能够明确标识按钮的功能。 

 

- (IBAction)loadActionSheet:(id)sender 
{
    UIActionSheet *actionSheet = [[UIActionSheet alloc] initWithTitle:@"Action Sheet窗口" 
                                                             delegate:self 
                                                    cancelButtonTitle:@"关闭" 
                                               destructiveButtonTitle:nil 
                                                    otherButtonTitles:@"显示Alert窗口", 
                                  @"do sth", @"do sth", nil];
    
    [actionSheet showInView:self.view];
    [actionSheet release];
}
//UIActionSheetDelegate协议的方法
- (void)actionSheet:(UIActionSheet *)actionSheet clickedButtonAtIndex:(NSInteger)buttonIndex
{
    switch (buttonIndex)
    {
        case 0:
        {
            UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"alert窗口" 
                                                            message:@"内容 btn1" 
                                                           delegate:self 
                                                  cancelButtonTitle:@"确认"
                                                  otherButtonTitles:nil];
            [alert show];
            [alert release];
        }
            break;
        case 1:
        {
            UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"alert窗口" 
                                                            message:@"内容 btn2" 
                                                           delegate:self 
                                                  cancelButtonTitle:@"确认"
                                                  otherButtonTitles:nil];
            [alert show];
            [alert release];
        }
            break;
        case 2:
        {
            UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"alert窗口" 
                                                            message:@"内容 btn3" 
                                                           delegate:self 
                                                  cancelButtonTitle:@"确认"
                                                  otherButtonTitles:nil];
            [alert show];
            [alert release];
        }
            break;
        case 3:
        {
            UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"关闭alert窗口" 
                                                            message:@"内容 关闭" 
                                                           delegate:self 
                                                  cancelButtonTitle:@"确认"
                                                  otherButtonTitles:nil];
            [alert show];
            [alert release];
        }
            break;
            
        default:
            break;
    }

} 

3.Modal Views 是弹出的相对独立的用户界面，在这个界面中用户可以完成一些相对独立于软件的事物，完成后可以退出Modal View返回软件界面。比较典型的例子包括在软件中发送邮件、从相片库中选取照片等。 

     设计使用Mdal View的时候需要注意几点：首先Modal View一般都是全屏，其次Modal View应该提供明确的让用户退出Modal View的按钮，一般做法是在上面显示导航条。 

       [self presentModalViewController:picker animated:YES];

    Modal View 示例参照：http://www.cnblogs.com/hanjun/archive/2012/11/22/2783266.html