iOS开发笔记--详解UILabel的相关属性设置

UILabel * label = [[UILabel alloc] initWithFrame:CGRectMake(50, 50, 200, 400)];  

label.frame = CGRectMake(97, 47, 223, 19);  

label.tag =101;  

label.text =@"abcd" 

NSString *labelText = @"abcd";  
label.text = labelText; 

label.font = [UIFont systemFontOfSize:12];//采用系统默认文字设置大小  
label.font = [UIFont fontWithName:@"Arial" size:30];//设置文字类型与大小 

label.textColor = [UIColor lightGrayColor];//其中textColor要用UIColor类型  

label.textAlignment = NSTextAlignmentLeft; 

label.lineBreakMode =NSLineBreakByCharWrapping;//其中lineBreakMode可选值为  
linBreakMode enum{  
NSLineBreakByWordWrapping = 0,//保留整个单词，以空格为边界  
  NSLineBreakByCharWrapping,//保留整个字符  
  NSLineBreakByClipping,//以边界为止  
  NSLineBreakByTruncatingHead,//省略开头，以省略号代替  
  NSLineBreakByTruncatingTail,//省略结尾，以省略号代替  
  NSLineBreakByTruncatingMiddle//省略中间，以省略号代替  
  }  

label.numberOfLines = 1;//行数设置为1,不设置时系统会默认行数为1 

[label sizeToFit];  

commentTextLabel.lineBreakMode = NSLineBreakByCharWrapping;  
commentTextLabel.numberOfLines = 0; 

label.numberOfLines =1;  
label.adjustsFontSizeToFitWidth =YES;  

CGSize size = [text sizeWithFont:font constrainedToSize:CGSizeMake(100, 180) lineBreakMode:NSLineBreakByCharWrapping];  

float maxHeight =50;//设置最大高度  
  float minFontSize =9;  
  float height;  
  int fontSize = 31;//设置最大字号  
  NSString *text = @"输入文本内容";  
  do {  
    fontSize = fontSize - 1;  
      UIFont *font =[UIFont fontWithName:@"Arial" size:fontSize];  
      CGSize size = [text sizeWithFont:font constrainedToSize:CGSizeMake(100, 180)/*宽度与label的宽度一样，高度应高于label高度*/ lineBreakMode:NSLineBreakByCharWrapping];  
    height = size.height;  
    NSLog(@"height=%f,fontSize=%d,text=%@",height,fontSize,text);  
  } while (height > maxHeight&&fontSize>minFontSize);  
  
  UILabel *label = [[UILabel alloc] initWithFrame:CGRectMake(50, 50, 100, 50)];  
  label.text =text;  
  if (fontSize ==9) {//判断字体是否小于最小字号，小于最小字号时就使用系统默认的缩略显示  
    label.font = [UIFont fontWithName:@"Arial" size:15];  
  }  
  else{  
  label.font = [UIFont fontWithName:@"Arial" size:fontSize];  
  label.lineBreakMode = NSLineBreakByCharWrapping;//实现文字多行显示  
  label.numberOfLines = 0;  
  }  
  [self.view addSubview:label];  

NSString *text =[[NSString alloc]init];  
 text = @"输入文本内容";  
 CGSize size = CGSizeMake(280, 180);  
 UIFont *fonts = [UIFont systemFontOfSize:14.0];  
 CGSize msgSie = [text sizeWithFont:fonts constrainedToSize:size lineBreakMode: NSLineBreakByCharWrapping];  
 UILabel *textLabel = [[UILabel alloc] init];  
 [textLabel setFont:[UIFont boldSystemFontOfSize:14]];  
 textLabel.frame = CGRectMake(20,70, 280,msgSie.height);  
 textLabel.text = text;  
 textLabel.lineBreakMode = NSLineBreakByCharWrapping;//实现文字多行显示  
 textLabel.numberOfLines = 0;  
 [self.view addSubview:textLabel];  
 设置label的边框粗细与颜色，设置前要在相应文件中加入#import<QuartzCore/QuartzCore.h>
 label.layer.borderColor = [UIColor lightGrayColor].CGColor;//边框颜色,要为CGColor  
label.layer.borderWidth = 1;//边框宽度  

label.backgroundColor =[UIColor yellowColor];  

UILabel * label = [[UILabel alloc] initWithFrame:CGRectMake(50, 50, 200, 400)];  
UIImageView *imageView =[[UIImageView alloc]init];  
imageView.frame =CGRectMake(50, 50, 200, 400);  
UIImage *image=[UIImage imageNamed:@"1.jpg"];  
imageView.image =image;//imageView会根据自身大小改变添加的图片的大小所以不需要额外设置image  
label.backgroundColor = [UIColor clearColor];  
label.text =@"hello world";  
label.font = [UIFont systemFontOfSize:30];  
label.textColor = [UIColor yellowColor];  
[self.view addSubview:imageView];//添加的顺序不能错，否则图片会覆盖label  
[self.view addSubview:label]; 

UIColor * color = [UIColor colorWithPatternImage:image];//image为需要添加的背景图  
 UILabel * label = [[UILabel alloc] initWithFrame:CGRectMake(50, 50, 100, 200)];  
 [label setBackgroundColor:color];  
 [self.view addSubview:label];  

 -(UIImage *)scaleImage:(UIImage *)img ToSize:(CGSize)itemSize{  
  UIImage *i;  
  // 创建一个bitmap的context,并把它设置成为当前正在使用的context  
  UIGraphicsBeginImageContext(itemSize);  
  CGRect imageRect=CGRectMake(0, 0, itemSize.width, itemSize.height);  
  // 绘制改变大小的图片  
  [img drawInRect:imageRect];  
  // 从当前context中创建一个改变大小后的图片  
  i=UIGraphicsGetImageFromCurrentImageContext();  
  // 使当前的context出堆栈  
  UIGraphicsEndImageContext();  
  // 返回新的改变大小后的图片  
  return i;  
}  

CGSize size= CGSizeMake(100, 200);  
  UIImage *image =[UIImage imageNamed:@"1.jpg"];  
  UIImage *laterImage =[self scaleImage:image ToSize:size];  
  UIColor * color = [UIColor colorWithPatternImage:laterImage];  
  UILabel * label = [[UILabel alloc] initWithFrame:CGRectMake(50, 50, 100, 200)];  
  [label setBackgroundColor:color];  
  [self.view addSubview:label];  

label.highLighted =YES; 

label.shadowColor =[UIColor grayColor];  

label.shadowOffset = CGSizeMake(2.0, 2.0);  

label.layer.cornerRadius = 10;