棄用'sizeWithFont：constrainedToSize：'替換

Question

有人知道如何在這種情況下使用-boundingRectWithSize：options：attributes：context：替代棄用的「sizeWithFont：constrainedToSize：」方法。

CGSize labelSize = [self.mainLabel.text sizeWithFont:self.mainLabel.font constrainedToSize:CGSizeMake(CGFLOAT_MAX, CGRectGetHeight(self.bounds))]; 

獲取警告： 'sizeWithFont：constrainedToSize：' 已過時：在IOS 7.0第一棄用 - 使用-boundingRectWithSize：選項：屬性：背景：

這是孔這段代碼：

// calculate the label size 

CGSize labelSize = [self.mainLabel.text sizeWithFont:self.mainLabel.font constrainedToSize:CGSizeMake(CGFLOAT_MAX, CGRectGetHeight(self.bounds))]; 

each_object(self.labels, ^(UILabel *label) { 
    CGRect frame = label.frame; 
    frame.origin.x = offset; 
    frame.size.height = CGRectGetHeight(self.bounds); 
    frame.size.width = labelSize.width + 2.f /*Magic number*/; 
    label.frame = frame; 


    // Recenter label vertically within the scroll view 
    label.center = CGPointMake(label.center.x, roundf(self.center.y - CGRectGetMinY(self.frame))); 

    offset += CGRectGetWidth(label.bounds) + self.labelSpacing; 
}); 

Answer 1

在你的那一刻...

CGSize labelSize = [self.mainLabel.text sizeWithFont:self.mainLabel.font constrainedToSize:CGSizeMake(CGFLOAT_MAX, CGRectGetHeight(self.bounds))]; 

因此，使用...

CGRect boundingRect = [self.mainLabel.text boundingRectWithSize:CGSizeMake(CGFLOAT_MAX, CGRectGetHeight(self.bounds)) 
                 options:NSStringDrawingUsesLineFragmentOrigin 
                 context:nil]; 

CGSize labelSize = boundingRect.size; 

這應該有效。

或者...帶屬性...

CGRect boundingRect = [self.mainLabel.text boundingRectWithSize:CGSizeMake(CGFLOAT_MAX, CGRectGetHeight(self.bounds)) 
                 options:NSStringDrawingUsesLineFragmentOrigin 
                attributes:@{NSFontAttributeName:self.mainLabel.font} 
                 context:nil]; 

Answer 2

例如這樣

-(CGFloat)getLabelSize:(UILabel *)label fontSize:(NSInteger)fontSize 
{ 


    NSDictionary *attributesDictionary = [NSDictionary dictionaryWithObjectsAndKeys: 
             [UIFont systemFontOfSize:fontSize], NSFontAttributeName, 
             nil]; 

    CGRect frame = [label.text boundingRectWithSize:CGSizeMake(270, 2000.0) 
             options:NSStringDrawingUsesLineFragmentOrigin 
            attributes:attributesDictionary 
             context:nil]; 

    CGSize size = frame.size; 

    return size.height; 
}