Login Form

目的：輸入帳號及密碼後，正確轉到另一頁面，錯誤顯示訊息。

Step 1.畫面上拉出"帳號"及“密碼”的Label & TextField，再來加入“登入”按鈕
如下圖

Step 2.設定帳號的TextField，如下圖
       （1）Placeholder:浮水印字
       （2）勾選"Clear when editing begins":代表要輸入時，先清除內容文字
       （3）Keyboard:選擇"E-mail Address":讓要輸入帳號時，有email ＠文字可供選擇

Step 3.設定密碼的TextField，如下圖
       （1）勾選Secure：此為密碼欄位

Step 4.ViewController.h,撰寫內容如下
@interface ViewController : UIViewController
{
    IBOutlet UITextField *account;
    IBOutlet UITextField *passwd;
}

@property (nonatomic, retain) IBOutlet UITextField *account;
@property (nonatomic, retain) IBOutlet UITextField *passwd;

-(IBAction)login:(id)sender;

Step 5.畫面上拖拉關聯如下

Step 6.新增“UIViewController subclass”命名為ContentView.

Step 7.ViewController.m,撰寫內容如下
 @synthesize account, passwd;
-(IBAction)login:(id)sender {
    NSString *usr = [account text];
    NSString *pad = [passwd text];
    iif([usr isEqualToString:@"john"] && [pad isEqualToString:@"123"]){
        //設定動畫
        [UIView beginAnimations:nil context:nil];
        [UIView setAnimationDuration:UIViewAnimationCurveEaseInOut];
        [UIView setAnimationDuration:2.0f];
   
        NSArray *xibs = [[NSBundle mainBundle]loadNibNamed:@"ContentVies" owner:self options:NULL];
        for(id obj in xibs){
            if([obj isKindOfClass:[UIViewController class]]){
                [self.navigationController pushViewController:obj animated:YES];
                break;
            }
        }
    }else{
        UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"錯誤訊息" message:@"登入失敗" delegate:self cancelButtonTitle:@"確定" otherButtonTitles:nil];
        [alert show];
    }
}