[IOS]（转）UILabel的高度跟宽度自适应

转自：http://www.jianshu.com/p/4c56c449eed3

1 创建category

.h中
+ (CGFloat)getHeightByWidth:(CGFloat)width title:(NSString *)title font:(UIFont*)font;

+ (CGFloat)getWidthWithTitle:(NSString *)title font:(UIFont *)font;

.m中
+ (CGFloat)getHeightByWidth:(CGFloat)width title:(NSString *)title font:(UIFont *)font
{

    UILabel *label = [[UILabel alloc] initWithFrame:CGRectMake(0, 0, width, 0)];
    label.text = title;
    label.font = font;
    label.numberOfLines = 0;
    [label sizeToFit];
    CGFloat height = label.frame.size.height;
    return height;
}

+ (CGFloat)getWidthWithTitle:(NSString *)title font:(UIFont *)font {
    UILabel *label = [[UILabel alloc] initWithFrame:CGRectMake(0, 0, 1000, 0)];
    label.text = title;
    label.font = font;
    [label sizeToFit];
    return label.frame.size.width;
}

2 使用时 引入头文件

#import "UILabel+LabelHeightAndWidth.h"

#pragma mark - labelOne  SizeToFitHeight
- (void)buildLabelOne
{
    UILabel *labelOne = [[UILabel alloc] initWithFrame:CGRectMake(10, 30, 200, 50)];
    labelOne.text = @"这是labelOne的高度自适应这是labelOne的高度自适应这是labelOne的高度自适应这是labelOne的高度自适应";
    labelOne.backgroundColor = [UIColor grayColor];
    labelOne.font = [UIFont systemFontOfSize:20];
    labelOne.numberOfLines = 0;
    CGFloat height = [UILabel getHeightByWidth:labelOne.frame.size.width title:labelOne.text font:labelOne.font];
    labelOne.frame = CGRectMake(10, 30, 200, height);
    [self.view addSubview:labelOne];

}

#pragma mark - labelTwo  SizeToFitWidth
- (void)buildLabelTwo
{
    UILabel *labelTwo = [[UILabel alloc] initWithFrame:CGRectMake(10, 300, 50, 100)];
    labelTwo.text = @"这是labelTwo的宽度自适应这是labelTwo的宽度自适应这是labelTwo的宽度自适应";
    labelTwo.backgroundColor = [UIColor cyanColor];
    labelTwo.font = [UIFont systemFontOfSize:20];
    CGFloat width = [UILabel getWidthWithTitle:labelTwo.text font:labelTwo.font];
    labelTwo.frame = CGRectMake(10, 300, width, 100);
    [self.view addSubview:labelTwo];
}

注意：如果需要在程序中某些位置调用API后获得数据再刷新lable的text，那么在刷新后text后再调用

CGFloat width = [UILabel getWidthWithTitle:labelTwo.text font:labelTwo.font];
labelTwo.frame = CGRectMake(10, 300, width, 100);

要不刷新的text可能长度可能大于初始化时设置的text

效果如下图