我目前有一个UILabel:
factLabel = [[UILabel alloc] initWithFrame:CGRectMake(20, 100, 280, 100)];
factLabel.text = @"some text some text some text some text";
factLabel.backgroundColor = [UIColor clearColor];
factLabel.lineBreakMode = UILineBreakModeWordWrap;
factLabel.numberOfLines = 10;
[self.view addSubview:factLabel];
在我的iOS应用程序的整个生命周期中，factLabel获得了许多不同的值。有的句子很多，有的只有5到6个单词。
我如何设置UILabel，使字体大小的变化，使文本总是适合我定义的界限?
当前回答
Swift 2.0版本:
private func adapteSizeLabel(label: UILabel, sizeMax: CGFloat) {
label.numberOfLines = 0
label.lineBreakMode = NSLineBreakMode.ByWordWrapping
let maximumLabelSize = CGSizeMake(label.frame.size.width, sizeMax);
let expectSize = label.sizeThatFits(maximumLabelSize)
label.frame = CGRectMake(label.frame.origin.x, label.frame.origin.y, expectSize.width, expectSize.height)
}
其他回答
它有点不复杂，但这应该是可行的， 例如，假设你想把你的uilabel设置为120x120，最大字体大小为28:
magicLabel.numberOfLines = 0;
magicLabel.lineBreakMode = NSLineBreakByWordWrapping;
...
magicLabel.text = text;
for (int i = 28; i>3; i--) {
CGSize size = [text sizeWithFont:[UIFont systemFontOfSize:(CGFloat)i] constrainedToSize:CGSizeMake(120.0f, CGFLOAT_MAX) lineBreakMode:NSLineBreakByWordWrapping];
if (size.height < 120) {
magicLabel.font = [UIFont systemFontOfSize:(CGFloat)i];
break;
}
}
minimumFontSize在iOS 6中已弃用。你可以使用minimumScaleFactor。
yourLabel.adjustsFontSizeToFitWidth=YES;
yourLabel.minimumScaleFactor=0.5;
这将照顾你的字体大小根据标签和文本的宽度。
下面是一个UILabel子类的填充代码，它实现了动画字体大小的改变:
@interface SNTextLayer : CATextLayer
@end
@implementation SNTextLayer
- (void)drawInContext:(CGContextRef)ctx {
// We override this to make text appear at the same vertical positon as in UILabel
// (otherwise it's shifted tdown)
CGFloat height = self.bounds.size.height;
float fontSize = self.fontSize;
// May need to adjust this somewhat if it's not aligned perfectly in your implementation
float yDiff = (height-fontSize)/2 - fontSize/10;
CGContextSaveGState(ctx);
CGContextTranslateCTM(ctx, 0.0, yDiff);
[super drawInContext:ctx];
CGContextRestoreGState(ctx);
}
@end
@interface SNAnimatableLabel ()
@property CATextLayer* textLayer;
@end
@interface SNAnimatableLabel : UILabel
- (void)animateFontToSize:(CGFloat)fontSize withDuration:(double)duration;
@end
@implementation SNAnimatableLabel
- (void)awakeFromNib {
[super awakeFromNib];
_textLayer = [SNTextLayer new];
_textLayer.backgroundColor = self.backgroundColor.CGColor;
_textLayer.foregroundColor = self.textColor.CGColor;
_textLayer.font = CGFontCreateWithFontName((CFStringRef)self.font.fontName);
_textLayer.frame = self.bounds;
_textLayer.string = self.text;
_textLayer.fontSize = self.font.pointSize;
_textLayer.contentsScale = [UIScreen mainScreen].scale;
[_textLayer setPosition: CGPointMake(CGRectGetMidX(_textLayer.frame), CGRectGetMidY(_textLayer.frame))];
[_textLayer setAnchorPoint: CGPointMake(0.5, 0.5)];
[_textLayer setAlignmentMode: kCAAlignmentCenter];
self.textColor = self.backgroundColor;
// Blend text with background, so that it doens't interfere with textlayer text
[self.layer addSublayer:_textLayer];
self.layer.masksToBounds = NO;
}
- (void)setText:(NSString *)text {
_textLayer.string = text;
super.text = text;
}
- (void)layoutSubviews {
[super layoutSubviews];
// Need to enlarge the frame, otherwise the text may get clipped for bigger font sizes
_textLayer.frame = CGRectInset(self.bounds, -5, -5);
}
- (void)animateFontToSize:(CGFloat)fontSize withDuration:(double)duration {
[CATransaction begin];
[CATransaction setAnimationDuration:duration];
_textLayer.fontSize = fontSize;
[CATransaction commit];
}
它是2015。我不得不去找一篇博客文章来解释如何在最新版本的iOS和XCode中使用Swift，这样它就可以与多行代码一起工作。
将“自动收缩”设置为“最小字体大小”。 将字体设置为理想的最大字体大小(我选择了20) 将“换行”从“换行”改为“截尾”。
来源: http://beckyhansmeyer.com/2015/04/09/autoshrinking-text-in-a-multiline-uilabel/
斯威夫特版本:
textLabel.adjustsFontSizeToFitWidth = true
textLabel.minimumScaleFactor = 0.5
