UIFontDownLoad ----动态下载系统提供的字体

程序运行结果如下 :

当点击对应单元格实现下载对应的字体.

控制台打印结果如下 :

2015-10-05 11:14:04.132 UIFontDownLoad[12721:86827] state 0 - {
}
2015-10-05 11:14:04.134 UIFontDownLoad[12721:86827] state 7 - {
    CTFontDescriptorMatchingResult =     (
        "UICTFontDescriptor <0x7fddd05388d0> = {\n    NSFontNameAttribute = Helvetica;\n    NSFontSizeAttribute = 12;\n}"
    );
    CTFontDescriptorMatchingSourceDescriptor = "UICTFontDescriptor <0x7fddd0797a80> = {\n    NSFont = \"STXingkai-SC-Light\";\n}";
}
2015-10-05 11:14:04.134 UIFontDownLoad[12721:86827] state 1 - {
    CTFontDescriptorMatchingResult =     (
        "UICTFontDescriptor <0x7fddd05388d0> = {\n    NSFontNameAttribute = Helvetica;\n    NSFontSizeAttribute = 12;\n}"
    );
}
2015-10-05 11:14:04.147 UIFontDownLoad[12721:85405] 字体已经匹配
2015-10-05 11:14:04.147 UIFontDownLoad[12721:85405] 字体下载完成
2015-10-05 11:14:05.562 UIFontDownLoad[12721:85405] STXingkai-SC-Light downloaded

程序实现的代码如下 :

//
//  ViewController.m
//  UIFontDownLoad
//
//  Created by mac1 on 15/10/5.
//  Copyright (c) 2015年 www.iphonetrain.com. All rights reserved.
//

#import "ViewController.h"

/*
 一种能够对文本格式和文本布局进行精细控制的文本引擎
 */
#import <CoreText/CoreText.h>

@interface ViewController ()<UITableViewDataSource,UITableViewDelegate>

@property (nonatomic,strong)NSArray *fontNames;
@property (nonatomic,strong)NSArray *fontSamples;
@property (nonatomic,strong)UITableView *myTableView;

@end

static NSString *identify = @"cell";

@implementation ViewController

- (void)viewDidLoad {
    [super viewDidLoad];
   
 
    self.view.backgroundColor = [UIColor greenColor];

[self addData];
    [self creatUI];
    
    
    
}

//初始化界面
- (void)creatUI
{
    _myTableView = [[UITableView alloc]initWithFrame:CGRectMake(0, 0, 320, 568)];
    _myTableView.dataSource = self;
    _myTableView.delegate = self;
    [self.view addSubview:_myTableView];
    
    
    /*
     注册单元格
    [_myTableView registerClass:[UITableViewCell class] forCellReuseIdentifier:identify];
     */
    
     
}

//初始化数据

- (void)addData
{
    _fontNames = [[NSArray alloc] initWithObjects:
                 @"STXingkai-SC-Light",
                 @"DFWaWaSC-W5",
                 @"FZLTXHK--GBK1-0",
                 @"STLibian-SC-Regular",
                 @"LiHeiPro",
                 @"HiraginoSansGB-W3",
                 nil];
    _fontSamples = [[NSArray alloc] initWithObjects:
                   @"汉体书写信息技术标准相",
                   @"容档案下载使用界面简单",
                   @"支援服务升级资讯专业制",
                   @"作创意空间快速无线上网",
                   @"兙兛兞兝兡兣嗧瓩糎",
                   @"㈠㈡㈢㈣㈤㈥㈦㈧㈨㈩",
                   nil];

}

//行数

- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
    return _fontNames.count;
    
}

//创建单元格

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{

//直接显示内容就不注册单元格

UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:identify];
    if (cell == nil) {
        cell = [[UITableViewCell alloc]initWithStyle:UITableViewCellStyleDefault reuseIdentifier:identify];
        
    }
    cell.textLabel.text = _fontNames[indexPath.row];

return cell;

}

- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
{
    [self asynchronouslySetFontName:_fontNames[indexPath.row]];
}

#pragma -mark -functions
//字体开始进行下载

- (void)asynchronouslySetFontName:(NSString *)fontName
{
    UIFont *aFont = [UIFont fontWithName:fontName size:12];
    
    //判断字体是否已经被下载
    if (aFont && ([aFont.fontName compare:fontName] == NSOrderedSame || [aFont.familyName compare:fontName] == NSOrderedSame))
    {
        NSLog(@"字体已经被下载");
        return;
    }

//用字体的PostScript名字创建一个Dictionary
    NSMutableDictionary *attrs = [NSMutableDictionary dictionaryWithObjectsAndKeys:fontName,kCTFontAttributeName, nil];
    
    
    // 创建一个字体描述对象CTFontDescriptorRef
    CTFontDescriptorRef desc = CTFontDescriptorCreateWithAttributes((__bridge CFDictionaryRef)attrs);
    
    //将字体描述对象放到一个NSMutableArray中
    NSMutableArray *descs = [NSMutableArray arrayWithCapacity:0];
    [descs addObject:(__bridge id)desc];
    CFRelease(desc);
    
    __block BOOL errorDuringDownload = NO;
    
    //开始对字体进行下载
    CTFontDescriptorMatchFontDescriptorsWithProgressHandler( (__bridge CFArrayRef)descs, NULL,  ^(CTFontDescriptorMatchingState state, CFDictionaryRef progressParameter) {
        
        NSLog( @"state %d - %@", state, progressParameter);
        
        double progressValue = [[(__bridge NSDictionary *)progressParameter objectForKey:(id)kCTFontDescriptorMatchingPercentage] doubleValue];
        
        
        if (state == kCTFontDescriptorMatchingDidBegin) {
            dispatch_async( dispatch_get_main_queue(), ^ {
                NSLog(@"字体已经匹配");
            });
        } else if (state == kCTFontDescriptorMatchingDidFinish) {
            dispatch_async( dispatch_get_main_queue(), ^ {
                NSLog(@"字体下载完成");
                
                // Log the font URL in the console
                CTFontRef fontRef = CTFontCreateWithName((__bridge CFStringRef)fontName, 0., NULL);
                CFStringRef fontURL = CTFontCopyAttribute(fontRef, kCTFontURLAttribute);
                CFRelease(fontURL);
                CFRelease(fontRef);
                
                if (!errorDuringDownload) {
                    NSLog(@"%@ downloaded", fontName);
                }
            });
        } else if (state == kCTFontDescriptorMatchingWillBeginDownloading) {
            dispatch_async( dispatch_get_main_queue(), ^ {
                NSLog(@"字体开始下载");
            });
        } else if (state == kCTFontDescriptorMatchingDidFinishDownloading) {
            dispatch_async( dispatch_get_main_queue(), ^ {
                NSLog(@"字体下载完成");
            });
        } else if (state == kCTFontDescriptorMatchingDownloading) {
            dispatch_async( dispatch_get_main_queue(), ^ {
                NSLog(@"下载进度");
            });
        } else if (state == kCTFontDescriptorMatchingDidFailWithError) {
            NSLog(@"下载失败");
            
            NSError *error = [(__bridge NSDictionary *)progressParameter objectForKey:(id)kCTFontDescriptorMatchingError];
            if (error != nil) {
                NSLog(@"errorMessage--%@-",[error description]);
            } else {
                NSLog(@"error message is not available");
            }
            errorDuringDownload = YES;
            dispatch_async( dispatch_get_main_queue(), ^ {
                NSLog(@"Download error: %@", [error description]);
            });
        }
        
        return (bool)YES;
    });
     
}