6.UIAlertView的基本使用

1.输入文字的alertView

• alertView 可以选择样式，有弹出让用户输入文字的样式以及怎么获得alertView上的UITextField:

  UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"修改数据" message:nil delegate:self cancelButtonTitle:@"取消" otherButtonTitles:@"确定", nil];
alert.alertViewStyle = UIAlertViewStylePlainTextInput;
UITextField *textField = [alert textFieldAtIndex:0];
//textField.text =hero.name;
textField.placeholder=hero.name;
[alert show];

• 通过代理拿到文字

  - (void)alertView:(UIAlertView *)alertView clickedButtonAtIndex:(NSInteger)buttonIndex{
UITextField *textField = [alertView textFieldAtIndex:0];
NSString *newStr = textField.text;
}