Question

-(IBAction)button:(id)sender
{
    button = [UIButton buttonWithType:UIBarButtonSystemItemRefresh];
    NSLog(@"Value of txtfrequency in button fuinction :%@",txtfrequency.text);
    int z = [txtfrequency.text  intValue];
    NSLog(@"Value of z is :%d",z);
    int y = 10;
    //create a new dynamic button
    for (int j=0; j<z; j++)
    {
        CGRect frame = CGRectMake(20, y , 50, 30);
        button = [UIButton buttonWithType:UIButtonTypeRoundedRect];
        [button setTag:j];
        button.frame = frame;
        CGRect frame1 = CGRectMake(100, y , 50, 30);

    textFieldRounded = [[UITextField alloc] initWithFrame:frame1];
    textFieldRounded.borderStyle =UIButtonTypeInfoDark;   //UITextBorderStyleNone;
    textFieldRounded.textColor = [UIColor blackColor]; //text color
    textFieldRounded.font = [UIFont systemFontOfSize:17.0];  //font size
    textFieldRounded.backgroundColor = [UIColor whiteColor]; //background color
    textFieldRounded.autocorrectionType = UITextAutocorrectionTypeNo;   // no auto correction support

    textFieldRounded.keyboardType = UIKeyboardTypeDefault;  // type of the keyboard
    textFieldRounded.returnKeyType = UIReturnKeyDone;  // type of the return key
    textFieldRounded.clearButtonMode = UITextFieldViewModeWhileEditing; // has a clear 'x' button to the right
    textFieldRounded.delegate = self;
    [textFieldRounded setTag:j];

    //[[scroll viewWithTag:j] removeFromSuperview];
    [button reloadInputViews];
    [textFieldRounded removeFromSuperview];

    //[scroll 

    [scroll addSubview:button];
    scroll.contentSize= CGSizeMake(100, 1400);
    [scroll addSubview:textFieldRounded];
    y= y+50;


} 
}

斐伊川..

只要用户输入按钮，上面的代码就会动态生成按钮。但是在这种情况下存在问题......例如用户已经给出输入以生成4个按钮..然后在视图中我们得到4个按钮但是现在如果用户想要只有2个按钮那么在视图上仍然有4个按钮。我无法引用或更新按钮的动作。

任何人都知道我该怎么做。

请帮帮我。

非常感谢。

Answer 1

尝试从scrollview中删除所有子视图。只需在向scrollview添加按钮之前创建一个枚举循环，如

 for(UIView *v in scroll){
     [v removeFromSuperView];
  }

将上面的代码放在循环之前。

Answer 2

您必须记住当前的按钮数量。我们假设您将其存储在numberOfButtons。

中

您可以清理现有的文本字段，

- (IBAction)button:(id)sender
{
    button = [UIButton buttonWithType:UIBarButtonSystemItemRefresh];
    int y = 10;

    for ( int i = 40; i < numberOfButtons+40; i++ ) {
        [[scroll viewWithTag:i] removeFromSuperview];
    }
    numberOfButtons = [txtfrequency.text intValue]; // Make `numberOfButtons` an ivar.

    for ( int i = 40; i < numberOfButtons+40; i++ ) {
        [..] // Add a button here.
    }
}

使用快速枚举的问题在于您将修改将引发错误的数组。

刷新或更新按钮操作

2 个答案: