UIStepper valueChanged.

Question

我正在制作一款iphone应用程序，我遇到了一个问题。

我正在制作包含标签和UIStepper的子视图。

它们由如下所示的for循环组成：

//subView to contain one ticket
    UIView *ticketTypeView = [[UIView alloc]initWithFrame:CGRectMake(10, y, 1000, 60)];
    if(ticketCount%2){
    ticketTypeView.backgroundColor = [UIColor lightGrayColor];
    }

    [self.view addSubview:ticketTypeView];

    //label for ticket type name
    UILabel *ticketType = [[UILabel alloc]initWithFrame:CGRectMake(10, 3, 500, 50)];
    [ticketType setText:string];
    [ticketType setFont:[UIFont fontWithName:@"Helvetica neue" size:20.0]];
    [ticketTypeView addSubview:ticketType];


    //UIStepper for ticket amount
    UIStepper *stepper = [[UIStepper alloc]initWithFrame:CGRectMake(500, 16, 0, 0)];
    stepper.transform = CGAffineTransformMakeScale(1.2, 1.2);
    [ticketTypeView addSubview:stepper];

    //label for price pr. ticket
    UILabel *pricePrTicket = [[UILabel alloc]initWithFrame:CGRectMake(620, 5, 100, 50)];
    [pricePrTicket setText:@"1000.00 Kr."];
    [ticketTypeView addSubview:pricePrTicket];

    //totalPrice label
    UILabel *totalTypePrice = [[UILabel alloc]initWithFrame:CGRectMake(900, 5, 100, 50)];
    [totalTypePrice setText:@"0.00 Kr."];
    [ticketTypeView addSubview:totalTypePrice];

现在.。如何为我的IBAction valueChanged添加UIStepper？步进应该取计数，乘以pricePrTicket并显示在totalPrice标签中。

任何帮助或暗示都将不胜感激:)

Answer 1

您需要将唯一的tag分配给您的ticketTypeView的所有子视图(每个子视图都应该是唯一的)，然后按照@thedjnivek回答。当您调用- (void) stepperChanged:(UIStepper*)theStepper方法时，获得这样的totalPrice标签对象，

UILabel *ticketprice = (UILabel *)[theStepper.superview viewWithTag:kTagPriceTicket];

检查标签对象是否为零，

if(ticketprice) {
   ticketprice.text = theStepper.value * pricePrTicket;
}

在创建ticketTypeView和其他标签的for循环中。

标签标记对于标签应该是唯一的，对于单个ticketTypeView视图也应该是唯一的。

创建这样的标记(您可以为标记提供任何整数)，

#define kTagTicketType 110
#define kTagPriceTicket 111
#define kTagTotalTypePrice 112

...
...
...

[ticketType setTag:kTagTicketType]; //NOTE this

[pricePrTicket setTag:kTagPriceTicket]; //NOTE this

[totalTypePrice setTag:kTagTotalTypePrice]; //NOTE this

在添加每个标签之前，先写上一行。

Answer 2

您必须像这样使用addTarget:action:设置目标：

[stepper addTarget:self action:@selector(stepperChanged:) forControlEvents:UIControlEventValueChanged];

- (void) stepperChanged:(UIStepper*)theStepper{
    //This method would be called on UIControlEventsValueChanged
}

我希望这能帮助你;)