以编程方式创建UITextField时出现问题iphone

Question

当我尝试以编程方式创建11个文本字段时，我很挣扎。问题是文本字段不显示。我在viewDidLoad方法中创建它们。

下面是我使用的代码：

- (void)viewDidLoad 
{ 
    // Determine some basic info 
    int numberOfTextfields = 11; 
    int textfieldHeight = 40; 
    int textfieldWidth = 200; 


    // Create the UIScrollView 
    UIScrollView *scrollView = [[UIScrollView alloc] initWithFrame:CGRectMake(0, 0, numberOfTextfields*textfieldHeight,textfieldWidth)]; 


    // Create all the textfields 
    NSMutableArray *textfields = [NSMutableArray arrayWithCapacity: 
            (NSUInteger)numberOfTextfields]; 
    for(int i = 0; i < numberOfTextfields; i++) { 
     UITextField *field = [[UITextField alloc] initWithFrame: 
           CGRectMake(0,i*textfieldHeight,textfieldHeight,textfieldWidth)]; 

     [scrollView addSubview:field]; 
     [textfields addObject:field]; 
    } 

    [super viewDidLoad]; 

} 

他们为什么不显示任何线索？

在此先感谢。

Answer 1

你似乎永远不会添加scrollView作为子视图。

---

您的textFields已被隐藏，因为您从未设置过边框样式。试试这个：

- (void)viewDidLoad 
{ 
    // Determine some basic info 
    int numberOfTextfields = 11; 
    int textfieldHeight = 40; 
    int textfieldWidth = 200; 


    // Create the UIScrollView 
    UIScrollView *scrollView = [[UIScrollView alloc] initWithFrame:CGRectMake(0, 0, textfieldWidth,numberOfTextfields*textfieldHeight)]; 
    scrollView.contentSize = CGSizeMake(numberOfTextfields*textfieldWidth, textfieldHeight); 

    // Create all the textfields 
    NSMutableArray *textfields = [NSMutableArray arrayWithCapacity: 
            (NSUInteger)numberOfTextfields]; 
    for(int i = 0; i < numberOfTextfields; i++) { 
     UITextField *field = [[UITextField alloc] initWithFrame:CGRectMake(0,i*textfieldHeight,textfieldWidth,textfieldHeight)]; 
     field.borderStyle = UITextBorderStyleRoundedRect; 
     [scrollView addSubview:field]; 
     [textfields addObject:field]; 
    } 

    [self.view addSubview:scrollView]; 

    [super viewDidLoad]; 
} 

Answer 2

您需要添加UIScrollView到您的视图和设置其内容区域，因为它不会自动地管理它（你可能已经预期）。

Answer 3

您需要将您的滚动视图添加到您的视图控制器。如果它被分配，
别的为此 self.view = [[UIView alloc] initWithFrame:CGRectMake (0,0,320,460)] 在端[self.view addSubview: scrollView]

Answer 4

检查这代码.....帧参数是（X，Y，宽度，高度）

int numberOfTextfields = 11; 
    int textfieldHeight = 40; 
    int textfieldWidth = 200; 


    // Create the UIScrollView 
    UIScrollView *scrollView = [[UIScrollView alloc] initWithFrame:CGRectMake(0, 0,textfieldWidth,numberOfTextfields*textfieldHeight)]; 


    // Create all the textfields 
    NSMutableArray *textfields = [NSMutableArray arrayWithCapacity: 
            (NSUInteger)numberOfTextfields]; 
    for(int i = 0; i < numberOfTextfields; i++) { 
     UITextField *field = [[UITextField alloc] initWithFrame: 
           CGRectMake(0,i*textfieldHeight,textfieldWidth,textfieldHeight)]; 
     field.borderStyle=UITextBorderStyleRoundedRect; 
     [scrollView addSubview:field]; 
     [textfields addObject:field]; 
    } 
    [self.view addSubview:scrollView]; 
    [super viewDidLoad]; 

Answer 5

添加此行

尝试下面的代码。文本框被添加，您可以滚动文本框。

 
int numberOfTextfields = 11; 
int textfieldHeight = 40; 
int textfieldWidth = 200;
 

UIScrollView *scrollView = [[UIScrollView alloc] initWithFrame:CGRectMake(0, 0,textfieldWidth,numberOfTextfields*textfieldHeight)]; scrollView.contentSize = CGSizeMake(textfieldWidth, numberOfTextfields*textfieldWidth+10);
 

NSMutableArray *textfields = [NSMutableArray arrayWithCapacity: (NSUInteger)numberOfTextfields];
 

for(int i = 1; i < numberOfTextfields; i++) { UITextField *field = [[UITextField alloc] initWithFrame: CGRectMake(0,i*textfieldHeight,textfieldWidth,textfieldHeight)]; field.borderStyle=UITextBorderStyleRoundedRect; [scrollView addSubview:field]; [textfields addObject:field]; }
 

[self.view addSubview:scrollView]; [super viewDidLoad];