iOS中字体的使用

有三种方式：
一、使用系统随附的字体
在使用之前，先把支持的所有字体打印出来，确保存在再使用：

// 打印所有的系统已存在的字体static void dumpAllFonts() {    NSInteger totalCount;    for (NSString *familyName in [UIFont familyNames]) {        NSArray *familyNameArr = [UIFont fontNamesForFamilyName:familyName];        NSLog(@"familyName:%@   count=%ld", familyName,[familyNameArr count]);        NSInteger tempCount = [familyNameArr count];        totalCount += tempCount;        for (NSString *fontName in familyNameArr) {            NSLog(@"++++     %@", fontName);        }    }    NSLog(@"totalCount=%ld",totalCount);}

使用就很简单了：

[UIFont fontWithName:@"字体的名字" size:14]

二、从外界拖进来的静态字体（也就是你的UI给你的字体，.ttf或者.ttc等格式的文件）
在使用前双击资源文件，mac会默认用‘字体册’打开，这时你会看到一些相关信息：

接下来就是开始了：
1、把资源拖进工程
2、TARGETS->Info->添加‘Fonts provide by application’项，如下：

3、TARGETS->Build Phases ->Copy Bundle Resources

4、到这里再次打印所有的字体，应该可以找到目标字体名，然后就可以像使用已存在的系统字体那样使用了。

三、下载系统字体使用
使用系统的API先把字体下载下来，然后就可以像普通已安装字体使用了。
这里是App可以根据需要安装的字体：https://support.apple.com/zh-cn/HT202599
这里是苹果提供的Demo：https://support.apple.com/zh-cn/HT202599
我是把下载字体的api简单地封装了一下,AsyDownloadSystemFont:

/** *  下载系统提供的字体 (异步) */#import <Foundation/Foundation.h>#import <UIKit/UIKit.h>typedef void(^DownloadingBlock)(CGFloat progressValue);typedef void(^DownloadSuccessBlock)(void);typedef void(^DownloadErrocBlock)(NSString *errorMsg);@interface AsyDownloadSystemFont : NSObject/** *  判断该字体有没有下载过 * *  @param fontName 字体名字 （不是文件夹的名字） * *  @return Yes:已经下载过  NO:没有下载过 */+(BOOL)isExistWithFontName:(NSString *)fontName;/** *  异步下载系统提供的字体 * *  @param fontName        字体名字 （不是文件夹的名字） *  @param loadingCallBack 下载中的回调   （可以改变进度条的值） *  @param sucessCallBack  下载成功的回调 (可以进行UI刷新) *  @param errorCalBack    下载失败的回调 */+(void)asyDownLoadFontWithFontName:(NSString *)fontName                       downloading:(DownloadingBlock)loadingCallBack                   downloadSuccess:(DownloadSuccessBlock)sucessCallBack                     downloadError:(DownloadErrocBlock)errorCalBack;@end#import "AsyDownloadSystemFont.h"#import <CoreText/CoreText.h>@implementation AsyDownloadSystemFont#pragma mark - Public Methods+(BOOL)isExistWithFontName:(NSString *)fontName {    UIFont *aFont = [UIFont fontWithName:fontName size:12.];    if (aFont && ([aFont.fontName compare:fontName] == NSOrderedDescending || [aFont.familyName compare:fontName] == NSOrderedSame)) {        NSLog(@"存在");        return YES;    }    NSLog(@"不存在");    return NO;}+(void)asyDownLoadFontWithFontName:(NSString *)fontName                       downloading:(DownloadingBlock)loadingCallBack                   downloadSuccess:(DownloadSuccessBlock)sucessCallBack                     downloadError:(DownloadErrocBlock)errorCalBack {    //1、准备参数    //用字体的PostScript名字创建一个NSDicitonary    NSMutableDictionary *attrs = [NSMutableDictionary dictionaryWithObjectsAndKeys:fontName, kCTFontNameAttribute,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);    //2、开始下载    CTFontDescriptorMatchFontDescriptorsWithProgressHandler((__bridge CFArrayRef)descs, NULL, ^bool(CTFontDescriptorMatchingState state, CFDictionaryRef  _Nonnull progressParameter) {        __block BOOL errorDuringDownload = NO;        double progressValue = [[(__bridge NSDictionary *)progressParameter objectForKey:(id)kCTFontDescriptorMatchingPercentage] doubleValue];        if (state == kCTFontDescriptorMatchingDidBegin) {            //字体已经匹配            NSLog(@"字体已经匹配");        }else if (state == kCTFontDescriptorMatchingDidFinish) {            if (!errorDuringDownload) {                //字体下载完成                NSLog(@"字体下载完成 －");                dispatch_async(dispatch_get_main_queue(), ^{                    if (sucessCallBack) {                        sucessCallBack();                    }                });            }        }else if (state == kCTFontDescriptorMatchingWillBeginDownloading) {            //字体开始下载        }else if (state == kCTFontDescriptorMatchingDidFinishDownloading) {            //字体下载完成  （可以在这里修改UI）            NSLog(@"字体下载完成  （可以在这里修改UI");            dispatch_async(dispatch_get_main_queue(), ^{                if (sucessCallBack) {                    sucessCallBack();                }            });        }else if (state == kCTFontDescriptorMatchingDownloading) {            //下载中            NSLog(@"下载中");            dispatch_async(dispatch_get_main_queue(), ^{                if (loadingCallBack) {                    loadingCallBack(progressValue);                }            });        }else if (state == kCTFontDescriptorMatchingDidFailWithError) {            NSString *errorMsg;            NSError *error = [(__bridge NSDictionary *)progressParameter objectForKey:(id)kCTFontDescriptorMatchingError];            if (!error) {                errorMsg = [errorMsg description];            }else {                errorMsg = @"Error Message Is Not Available!";            }            dispatch_async(dispatch_get_main_queue(), ^{                if (errorCalBack) {                    errorCalBack(errorMsg);                }            });            NSLog(@"errorMsg＝%@",errorMsg);            //设置标志            errorDuringDownload = YES;        }        return YES;    });}@end

下面就是具体的使用：

#import "DynamicViewController.h"#import "AsyDownloadSystemFont.h"#import "UIView+FrameHelp.h"static NSArray *kFontNames() {    NSArray *fontNames = nil;    if (!fontNames) {        fontNames = @[                      @"STXingkai-SC-Light",                      @"DFWaWaSC-W5",                      @"FZLTXHK--GBK1-0",                      @"STLibian-SC-Regular",                      @"LiHeiPro",                      @"HiraginoSansGB-W3"                      ];    }    return fontNames;}static NSArray *kFontSamples() {    NSArray *fontSamples = nil;    if (!fontSamples) {        fontSamples = @[                        @"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"                        ];    }    return fontSamples;}@interface DynamicViewController () <UITableViewDataSource,UITableViewDelegate>{    NSString *_fontName;}@property (nonatomic, retain) UITableView *kTableView;@property (nonatomic, retain) UIProgressView *kProgress;@property (nonatomic, retain) UITextView     *kTextView;@property (nonatomic, retain) UIActivityIndicatorView *kActivityView;@end@implementation DynamicViewController#pragma mark - Life Cycle- (void)viewDidLoad {    [super viewDidLoad];    [self uiConfig];}#pragma mark - UITableViewDataSource-(NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section {    return [kFontNames() count];}-(UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {    NSArray *fontName = kFontNames();    static NSString *cellId = @"cellId";    UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:cellId];    if (!cell) {        cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:cellId];    }    cell.textLabel.text = [fontName objectAtIndex:indexPath.row];    return cell;}#pragma mark - UITableViewDelegate-(void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath {    [tableView deselectRowAtIndexPath:indexPath animated:YES];    _fontName = [kFontNames() objectAtIndex:indexPath.row];    BOOL isExist = [AsyDownloadSystemFont isExistWithFontName:_fontName];    if (isExist) {        NSString *text = [kFontSamples() objectAtIndex:indexPath.row];        [self refrshTextViewWithText:text];    }else {        NSString *samples = [kFontSamples() objectAtIndex:indexPath.row];        [AsyDownloadSystemFont asyDownLoadFontWithFontName:_fontName downloading:^(CGFloat progressValue) {            [self.kProgress setHidden:NO];            self.kProgress.progress = progressValue/100;            [self.kActivityView startAnimating];        } downloadSuccess:^{            [self.kProgress setHidden:YES];            [self.kActivityView stopAnimating];            [self refrshTextViewWithText:samples];        } downloadError:^(NSString *errorMsg) {            [self.kProgress setHidden:YES];            [self.kActivityView stopAnimating];            NSLog(@"errorMsg=%@",errorMsg);        }];    }}-(void)refrshTextViewWithText:(NSString *)text {    self.kTextView.font = [UIFont fontWithName:_fontName size:14.];    self.kTextView.text = text;}#pragma mark - Private Methods-(void)uiConfig {    self.view.backgroundColor = [UIColor whiteColor];    self.kTableView = [[UITableView alloc] initWithFrame:CGRectMake(0, 0, self.view.width, 400) style:UITableViewStylePlain];    self.kTableView.tableFooterView = [UIView new];    self.kTableView.dataSource = self;    self.kTableView.delegate = self;    self.kProgress = [[UIProgressView alloc] initWithFrame:CGRectMake((self.view.width-150)/2, self.view.height-100, 150, 10)];    self.kProgress.userInteractionEnabled = NO;    [self.kProgress setHidden:YES];    self.kTextView = [[UITextView alloc] initWithFrame:CGRectMake((self.view.width-150)/2, self.view.height-150, 150, 30)];    self.kActivityView = [[UIActivityIndicatorView alloc] initWithActivityIndicatorStyle:UIActivityIndicatorViewStyleGray];    self.kActivityView.hidesWhenStopped = YES;    [self.view addSubview:self.kTableView];    [self.view addSubview:self.kProgress];    [self.view addSubview:self.kTextView];    self.navigationItem.titleView = self.kActivityView;}@end