1.按鈕（Button）

- (void)addButton:(id)sender
{
    //創建一個按鈕
    UIButton *pBtton = [UIButton buttonWithType:UIButtonTypeRoundedRect];
    //設置區域
    [pBtton setFrame:CGRectMake(10, 70, 100, 40)];
    //設置按鈕的標題和響應方式
    [pBtton setTitle:@"Normal" forState:UIControlStateNormal];
    //允許顯示高亮
    pBtton.showsTouchWhenHighlighted = YES;
    //為按鈕設置方法，需要寫出方法的實現
    [pBtton addTarget:self action:@selector(buttonDown:) forControlEvents:UIControlEventTouchDown];
    //把方法加到當前的視圖中
    [self.view addSubview:pBtton];
}

2.標簽欄（Label）

- (void)addLabel:(id)sender
{
    //創建一個label
    UILabel *pLabel = [[UILabel alloc]initWithFrame:CGRectMake(10, 10, 120, 50)];
    //內容
    pLabel.text = @"HelloWorld\nSecondLine";
    //設置字體和大小
    pLabel.font = [UIFont fontWithName:@"Verdana" size:18];
    //字體對齊方式
    pLabel.textAlignment = NSTextAlignmentCenter;
    //字體顏色
    pLabel.textColor = [UIColor redColor];
    //顯示行數
    pLabel.numberOfLines = 2;
    //陰影顏色
    pLabel.shadowColor = [UIColor blackColor];
    //陰影尺寸
    pLabel.shadowOffset = CGSizeMake(2.0,1.0);
    //設置label的背景色為透明色
    pLabel.backgroundColor = [UIColor clearColor];
    //把標簽添加到當前視圖
    [self.view addSubview:pLabel];
    //把創建的變量釋放
    [pLabel release];
}

3.文本欄（textField）

- (void)addTextField:(id)sender
{
    //創建TextField
    UITextField *pTextField = [[UITextField alloc]initWithFrame:CGRectMake(10, 116, 200, 31)];
    //設置邊框樣式
    pTextField.borderStyle = UITextBorderStyleRoundedRect;	
    //設置字體
    pTextField.font = [UIFont systemFontOfSize:18.0];
    //根據寬度改變字體
    pTextField.adjustsFontSizeToFitWidth = YES;
    //最小字體
    pTextField.minimumFontSize = 2.0;
    //清除按鈕的樣式
    pTextField.clearButtonMode = UITextFieldViewModeWhileEditing;
    //彈出的鍵盤的樣式
    pTextField.keyboardType = UIKeyboardTypeDefault;	
    //設置使用自動更正功能
    pTextField.autocorrectionType = UITextAutocorrectionTypeNo;
    //設置鍵盤自動大小寫的屬性
    pTextField.autocapitalizationType = UITextAutocapitalizationTypeNone;
    //設置返回按鈕類型
    pTextField.returnKeyType = UIReturnKeyDone;	
    //設置是否支持密碼文本顯示
    pTextField.secureTextEntry = YES;	
    //設置委托
    pTextField.delegate = self;
    //把文本欄添加到當前視圖
    [self.view addSubview:pTextField];
    //把創建的變量釋放
    [pTextField release];
}

遵循UITextFieldDelegate協議，實現鍵盤的彈回方法

- (BOOL)textFieldShouldReturn:(UITextField *)textField
{
    //放當前的textField放棄第一響應者
    [textField resignFirstResponder];
    return YES;
}

遵循UITextFieldDelegate協議，實現控制文本欄字符串的輸入長度控制

- (BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string
{
    //設置最大可輸入的字符長度
    int MAX_LENGTH = 10;
    NSMutableString *pNewString = [NSMutableString stringWithString:textField.text];
    //完成range內字符串的替換
    [pNewString replaceCharactersInRange:range withString:string];
    //根據兩個的長度判斷,返回YES or NO.
    return ([pNewString length] <= MAX_LENGTH);
}