iPhone UILabel sizeWithFont： [英] iPhone UILabel sizeWithFont:

问题描述

我试图测量一个NSString的可视大小，它考虑到我可以渲染的行数。但是，sizeWithFont不考虑numberOfLines属性？所以我的布局算法将所有的东西放在比实际需要的更低的位置。

  _price = [[UILabel alloc] init]; 
 _price.text = myPriceValue; 
 _price.lineBreakMode = UILineBreakModeWordWrap; 
 _price.numberOfLines = 3; 
 _price.backgroundColor = [UIColor clearColor]; 
 _price.textColor = TTSTYLEVAR（colorPrice）; 
 ///后面的代码忽略了numberOfLines，只是告诉我整个块的大小。 
 //我想让它知道numberOfLines 
 // 
 CGSize priceSize = [_price.text sizeWithFont：_price.font 
 constrainedToSize：CGSizeMake（maxWidth，CGFLOAT_MAX） 
 lineBreakMode：UILineBreakModeWordWrap]; 
  

有谁知道如何使用iPhone SDK做到这一点？

解决方案

而不是CGFLOAT_MAX文本计算的最大高度，请尝试获取一行的大小：

  [_ price.text sizeWithFont：_price.font] .height 
  

然后将其乘以所需的最大行数，然后将其插入到所限制的大小的高度。它可能看起来像这样：

$ p $ _price = [[UILabel alloc] init];
_price.text = myPriceValue;
_price.lineBreakMode = UILineBreakModeWordWrap;
_price.numberOfLines = 3;
_price.backgroundColor = [UIColor clearColor];
_price.textColor = TTSTYLEVAR（colorPrice）;
CGFloat lineHeight = [_price.text sizeWithFont：_price.font] .height;
CGSize priceSize = [_price.text sizeWithFont：_price.font
constrainedToSize：CGSizeMake（maxWidth，lineHeight * _price.numberOfLines）
lineBreakMode：UILineBreakModeWordWrap];


如果您将行数设置为0，则最大高度将为0在这种情况下;那么您应该使用CGFLOAT_MAX。

I'm trying to measure the visual size of a NSString that takes into account the number of lines I can render. However, sizeWithFont doesn't take into account numberOfLines property? So my layout algorithm positions everything lower than they actually need to be.

_price = [[UILabel alloc] init];
_price.text = myPriceValue;
_price.lineBreakMode = UILineBreakModeWordWrap;
_price.numberOfLines = 3;
_price.backgroundColor = [UIColor clearColor];
_price.textColor = TTSTYLEVAR(colorPrice);
/// the follow code ignores numberOfLines and just tells me the size of the whole block.  
// I'd like it to be aware of numberOfLines
//
CGSize priceSize = [_price.text sizeWithFont:_price.font
        constrainedToSize:CGSizeMake(maxWidth, CGFLOAT_MAX)
        lineBreakMode:UILineBreakModeWordWrap];

Does anyone know how to do this using the iPhone SDK?

解决方案

Instead of CGFLOAT_MAX for the max height of your text calculation, try getting the size of one line with this:

[_price.text sizeWithFont:_price.font].height

and then multiplying that by the maximum # of lines you want, then plugging that into the height of the size you are constraining yourself to. It'd probably look like this:

_price = [[UILabel alloc] init];
_price.text = myPriceValue;
_price.lineBreakMode = UILineBreakModeWordWrap;
_price.numberOfLines = 3;
_price.backgroundColor = [UIColor clearColor];
_price.textColor = TTSTYLEVAR(colorPrice);
CGFloat lineHeight = [_price.text sizeWithFont:_price.font].height;
CGSize priceSize = [_price.text sizeWithFont:_price.font
        constrainedToSize:CGSizeMake(maxWidth, lineHeight * _price.numberOfLines)
        lineBreakMode:UILineBreakModeWordWrap];

Don't use this if you ever set number of lines to 0 as your max height will be 0 in that case; you should use CGFLOAT_MAX then.

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