本文共 4025 字，大约阅读时间需要 13 分钟。

0:首先还是通过纯的代码来实现

0：删除3个文件ViewController.h，ViewController.m，Main.storyboard

1：修改点击左边的蓝色按钮，然后选择general－》developer info－》main interface ，将这个main interface 晴空

2：然后再创建一个MainUIViewController ,它继承自UIViewController

1:AppDelegate.m的didfinshlaunchingwithoptions方法的更新

////  MainUiViewController.m//  FourthDemo////  Created by 千雅爸爸 on 16/10/9.//  Copyright © 2016年 kodulf. All rights reserved.//#import "MainUiViewController.h"@interface MainUiViewController ()@end@implementation MainUiViewController- (void)viewDidLoad {    [super viewDidLoad];    [self.view setBackgroundColor:[UIColor whiteColor]];     //使用宏定义来注释掉if 0 endif#if 0    UILabel *label =[[UILabel alloc] initWithFrame:CGRectMake(100, 100, 200, 200)];        [self.view addSubview:label];        label.text = @"Hello World";    //UILable 默认的就是没有背景色的    label.backgroundColor =[UIColor greenColor];    label.textColor = [UIColor whiteColor];// 字体颜色    label.font = [UIFont systemFontOfSize:20];//字体大小    label.textAlignment = NSTextAlignmentCenter;//居中显示    //查找支持的肢体    NSArray *fontList = [UIFont familyNames];    NSLog(@"字体%@",fontList);    //设置字体和大小    label.font =[UIFont fontWithName:@"Papyrus" size:20];        label.text=@"888888888888888888888/默认的行数为1，如果是0表示无数行；这里是88888888888888888888888888888888888888888888888888888888888";    label.numberOfLines=4;//默认的行数为1，如果是0表示无数行；这里是4行，如果只能显示3行，显示不下了还是使用省略号                //考虑文本的大小根据文本的内容改变＋＋＋＋＋＋开始＋＋＋＋＋＋＋    label.numberOfLines = 0;    CGSize maxSize = CGSizeMake(CGRectGetWidth(label.frame), CGFLOAT_MAX);//这里的lable.frame来获取长度，    CGSize textSize = [label.text boundingRectWithSize:maxSize options:NSStringDrawingUsesLineFragmentOrigin|NSStringDrawingUsesFontLeading attributes:@{NSFontAttributeName:[UIFont fontWithName:@"Papyrus" size:20]} context:nil].size;    //NSStringDrawingUsesLineFragmentOrigin如果没有这个选项，可能会导致我们计算出错，这个事必须加入的    //NSStringDrawingUsesFontLeading 考虑行高的计算的    //attributes 是label 原有的属性例如这里是attributes:{NSFontAttributeName:[UIFont fontWithName:@"Papyrus" size:20]}    //context一般都是传nil    //别忘了最后的.size        CGRect frame = label.frame;    frame.size = textSize;//更改size    label.frame = frame;    //考虑文本的大小根据文本的内容改变＋＋＋＋＋＋结束＋＋＋＋＋＋＋#endif        //风格化的文本显示内容    NSString *aString = @"iOS";    UILabel *uiLabel = [[UILabel alloc]initWithFrame:CGRectMake(0, 200, 375, 45)];    [self.view addSubview:uiLabel];    uiLabel.text=aString;    uiLabel.textAlignment = NSTextAlignmentCenter;    NSLog(@"属性的文字%@",uiLabel.attributedText);        NSMutableAttributedString *attributeString = [[NSMutableAttributedString alloc]initWithString:aString];//可变的属性后的字符串，    [attributeString addAttribute:NSFontAttributeName value:[UIFont systemFontOfSize:50] range:NSMakeRange(0, 1)];//这个太溜了，可以分开来定义字体，和java相比太溜了。    [attributeString addAttribute:NSBackgroundColorAttributeName value:[UIColor greenColor] range:NSMakeRange(0, 1)];    [attributeString addAttribute:NSBackgroundColorAttributeName value:[UIColor yellowColor] range:NSMakeRange(1, 2)];        uiLabel.attributedText = [attributeString copy];//可以直接赋值，但是为了防止误操作，因为attributeString是可变的，而uiLabel.attributedText是不可变的，所以最好是用copy来做        // Do any additional setup after loading the view.}- (void)didReceiveMemoryWarning {    [super didReceiveMemoryWarning];    // Dispose of any resources that can be recreated.}/*#pragma mark - Navigation// In a storyboard-based application, you will often want to do a little preparation before navigation- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender {    // Get the new view controller using [segue destinationViewController].    // Pass the selected object to the new view controller.}*/@end