在ios7中,sizeWithFont:现在已弃用。我现在如何在UIFont对象传递到替换方法sizeWithAttributes:?


当前回答

// max size constraint
CGSize maximumLabelSize = CGSizeMake(184, FLT_MAX)

// font
UIFont *font = [UIFont fontWithName:TRADE_GOTHIC_REGULAR size:20.0f];

// set paragraph style
NSMutableParagraphStyle *paragraphStyle = [[NSMutableParagraphStyle alloc] init];
paragraphStyle.lineBreakMode = NSLineBreakByWordWrapping;

// dictionary of attributes
NSDictionary *attributes = @{NSFontAttributeName:font,
                             NSParagraphStyleAttributeName: paragraphStyle.copy};

CGRect textRect = [string boundingRectWithSize: maximumLabelSize
                                     options:NSStringDrawingUsesLineFragmentOrigin
                                  attributes:attributes
                                     context:nil];

CGSize expectedLabelSize = CGSizeMake(ceil(textRect.size.width), ceil(textRect.size.height));

其他回答

替代解决方案,

CGSize expectedLabelSize;
if ([subTitle respondsToSelector:@selector(sizeWithAttributes:)])
{
    expectedLabelSize = [subTitle sizeWithAttributes:@{NSFontAttributeName:subTitleLabel.font}];
}else{
    expectedLabelSize = [subTitle sizeWithFont:subTitleLabel.font constrainedToSize:subTitleLabel.frame.size lineBreakMode:NSLineBreakByWordWrapping];
}

你仍然可以使用sizeWithFont。但是,在iOS >= 7.0中,如果字符串包含开头和结尾空格或结束行\n,则会导致崩溃。

在使用文本之前修剪文本

label.text = [label.text stringByTrimmingCharactersInSet:
             [NSCharacterSet whitespaceAndNewlineCharacterSet]];

这也适用于sizeWithAttributes和[label sizeToFit]。

此外,当你有nsstringdrawingtextstorage消息发送到deallocated实例在ios7.0设备它处理这个。

在iOS7中,我需要逻辑来为tableview返回正确的高度:highightforrowatindexpath方法,但sizeWithAttributes总是返回相同的高度,而不管字符串长度,因为它不知道它将被放在一个固定宽度的表格单元格。我发现这对我来说很有用,并计算出正确的高度,考虑到表格单元格的宽度!这是基于上面T先生的回答。

NSString *text = @"The text that I want to wrap in a table cell."

CGFloat width = tableView.frame.size.width - 15 - 30 - 15;  //tableView width - left border width - accessory indicator - right border width
UIFont *font = [UIFont systemFontOfSize:17];
NSAttributedString *attributedText = [[NSAttributedString alloc] initWithString:text attributes:@{NSFontAttributeName: font}];
CGRect rect = [attributedText boundingRectWithSize:(CGSize){width, CGFLOAT_MAX}
                                           options:NSStringDrawingUsesLineFragmentOrigin
                                           context:nil];
CGSize size = rect.size;
size.height = ceilf(size.height);
size.width  = ceilf(size.width);
return size.height + 15;  //Add a little more padding for big thumbs and the detailText label

正如@Ayush的回答:

正如你在苹果开发者网站上看到的sizeWithFont,它已被弃用,所以我们需要使用sizeWithAttributes。

好吧,假设在2019+你可能会使用Swift和String而不是Objective-c和NSString,下面是使用预定义字体获取字符串大小的正确方法:

let stringSize = NSString(string: label.text!).size(withAttributes: [.font : UIFont(name: "OpenSans-Regular", size: 15)!])
- (CGSize) sizeWithMyFont:(UIFont *)fontToUse
{
    if ([self respondsToSelector:@selector(sizeWithAttributes:)])
    {
        NSDictionary* attribs = @{NSFontAttributeName:fontToUse};
        return ([self sizeWithAttributes:attribs]);
    }
    return ([self sizeWithFont:fontToUse]);
}