UILabel垂直居中，自动收缩

5 回答

• 2

  根据我的经验，您可以将 -[UILabel baselineAdjustment] 属性设置为 UIBaselineAdjustmentAlignCenters 以实现您所描述的效果 .

  来自docs：

  baselineAdjustment控制文本需要缩小以适应标签时如何调整文本基线 . @property（非原子）UIBaselineAdjustment baselineAdjustment
  讨论如果adjustsFontSizeToFitWidth属性设置为YES，则此属性控制在需要调整字体大小的情况下文本基线的行为 . 此属性的默认值为UIBaselineAdjustmentAlignBaselines . 仅当numberOfLines属性设置为1时，此属性才有效 .

  和

  UIBaselineAdjustmentAlignCenters相对于其边界框的中心调整文本 .

  EDIT: adding a full view-controller that demonstrates this:

  @interface TSViewController : UIViewController
  @end
  
  @implementation TSViewController
  
  - (void) addLabelWithFrame: (CGRect) f baselineAdjustment: (UIBaselineAdjustment) bla
  {
      UILabel* label = [[UILabel alloc] initWithFrame: f];
      label.baselineAdjustment = bla;
      label.adjustsFontSizeToFitWidth = YES;
      label.font = [UIFont fontWithName: @"Courier" size: 200];
      label.text = @"00";
      label.textAlignment = NSTextAlignmentCenter;
      label.backgroundColor = [UIColor lightGrayColor];
      label.userInteractionEnabled = YES;
      [self.view addSubview: label];
  
      UIView* centerline = [[UIView alloc] initWithFrame: CGRectMake(f.origin.x, f.origin.y+(f.size.height/2.0), f.size.width, 1)];
      centerline.backgroundColor = [UIColor redColor];
      [self.view addSubview: centerline];
  
      UITapGestureRecognizer* tgr = [[UITapGestureRecognizer alloc] initWithTarget: self action: @selector(onTap:)];
      [label addGestureRecognizer: tgr];
  }
  
  - (void) viewDidLoad
  {
      [super viewDidLoad];
  
      [self addLabelWithFrame: CGRectMake(0, 0, 320, 200)
           baselineAdjustment: UIBaselineAdjustmentAlignCenters];
  
      [self addLabelWithFrame: CGRectMake(0, 220, 320, 200)
           baselineAdjustment: UIBaselineAdjustmentAlignBaselines];
  }
  
  - (void) onTap: (UITapGestureRecognizer*) tgr
  {
      UILabel* label = (UILabel*)tgr.view;
      NSString* t = [label.text stringByAppendingString: @":00"];
      label.text = t;
  }
  
  @end
  

  回复于 2024-04-27T16:32:50+08:00
• 1

  -(void)fitVerticallyToLabel:(UILabel *)lbl
  {
      CGFloat fontSize = lbl.frame.size.width / lbl.text.length;
      [lbl setFont:[UIFont fontWithName:@"Helvetica-Bold" size:fontSize]];
  
      CGRect rect = lbl.frame;
      rect.origin.y += rect.size.height - fontSize;
      rect.size.height = fontSize;
      [lbl setFrame:rect];
  }
  

  How to Use: Call this method after setting the text to your label.

  label.text = @"text";
      [self fitVerticallyToLabel:label];
  

  

  

  Note: I ahev taken UILabel from xib. You can take it programmatically too in that case you will have to set its text alignment NSTextAlignMentCenter

  回复于 2024-04-27T16:32:50+08:00
• -4

  在IB中工作时，请务必将对齐基线设置为居中

  

  Note: line break CANNOT be word wrap for this to work, so it will NOT work multiline (good to set the line break to Truncate tail)

  回复于 2024-04-27T16:32:50+08:00
• 92

  尝试实现此逻辑：

  -(void)adjustLabel1Text1:(NSString *)text1 
  {
      UILabel *lbl_first = [UIFont fontWithName:@"Helvetica" size:12];
  
  
  
      text1 = [text1 stringByTrimmingCharactersInSet:[NSCharacterSet whitespaceAndNewlineCharacterSet]];
  
  
      float hedingLblHeight = [self calculateHeightOfTextFromWidth:text1 : [UIFont fontWithName:@"Helvetica" size:12] :118 :UILineBreakModeWordWrap];
  
      lbl_first.text=text1;
  
  
      [lbl_first setFrame:CGRectMake(lbl_first.frame.origin.x, lbl_first.frame.origin.y, 118, hedingLblHeight)];
      lbl_first.lineBreakMode = UILineBreakModeWordWrap;
      lbl_first.numberOfLines = 0;
      [lbl_first sizeToFit];
  
  
  
  
  //////////Adjust the lable or any UIControl below this label accordingly.
  
      float endResultHeight=[self calculateHeightOfTextFromWidth:text2 : [UIFont fontWithName:@"Helvetica" size:15] :299 :UILineBreakModeWordWrap];
  
      if(hedingLblHeight>secondImgTitleHeight)
      {
      [lbl_endResult setFrame:CGRectMake(lbl_endResult.frame.origin.x, lbl_first.frame.origin.y+lbl_first.frame.size.height+5, 299, endResultHeight)];
      }
      else
      {
          [lbl_endResult setFrame:CGRectMake(lbl_endResult.frame.origin.x, lbl_first.frame.origin.y+lbl_first.frame.size.height+5, 299, endResultHeight)];
  
      }
  
      lbl_endResult.lineBreakMode=UILineBreakModeWordWrap;
      lbl_endResult.numberOfLines = 0;
      [lbl_endResult sizeToFit];
  
  
  
  }
  
  -(float) calculateHeightOfTextFromWidth:(NSString*)text : (UIFont*) withFont:(float)width :(UILineBreakMode)lineBreakMode
  {
  
      CGSize suggestedSize = [text sizeWithFont:withFont constrainedToSize:CGSizeMake(width, FLT_MAX) lineBreakMode:lineBreakMode];
  
      return suggestedSize.height;
  }
  

  它给了我很多帮助 . 希望它适合你 .

  回复于 2024-04-27T16:32:50+08:00
• 2

  尝试

  yourLabel.textAlignment = UITextAlignmentCenter;
  

  回复于 2024-04-27T16:32:50+08:00