iOS 在线下载字体

来源：互联网发布：淘宝网王麻子羊肉刀编辑：程序博客网时间：2024/04/29 08:15

转自：http://www.cnblogs.com/jijiYY/p/4736967.html

教你如何在iOS项目中设置各种字体

在iOS开发中设置字体的方法有很多种，下面为大家介绍比较常用的三种方法

1.使用系统默认提供的字体

系统默认提供的字体主要是指UIFont中提供的字体，其使用代码为：

fontLabel.font = [UIFont fontWithName:@"Marion" size:17];

或者是通过字体详细字典对字体属性进行设置

/*     UIFontDescriptorFamilyAttribute：设置字体家族名     UIFontDescriptorNameAttribute  ：设置字体的字体名     UIFontDescriptorSizeAttribute  ：设置字体尺寸     UIFontDescriptorMatrixAttribute：设置字体形变     */    UIFontDescriptor *attributeFontDescriptor = [UIFontDescriptor fontDescriptorWithFontAttributes:                                                 @{UIFontDescriptorFamilyAttribute: @"Marion",                                                   UIFontDescriptorNameAttribute:@"Marion-Regular",                                                   UIFontDescriptorSizeAttribute: @40.0,                                                   UIFontDescriptorMatrixAttribute:[NSValue valueWithCGAffineTransform:CGAffineTransformMakeRotation(M_1_PI*1.5)                                                                                    ]}];    fnotLabel.font = [UIFont fontWithDescriptor:attributeFontDescriptor size:0.0];

其中的字体家族名和字体名可以通过以下方法获取

NSLog(@"familyNames：%@",[UIFont familyNames]);

以上两种方法均可以为label设置字体，但是全部是只针对英文数字，对中文无效。要想改变中文字体还需要使用后面两种办法

2.动态下载字体

iOS6以后苹果就开始支持动态下载中文字体已供应用中展示个性字体的需求，由于下载的时候需要使用的名字是PostScript名称，需要使用Mac内自带的应用“字体册“来获得相应字体的PostScript名称。如下显示了从”字体册“中获取《娃娃体-繁常规体》字体的PostScript名称的截图

具体代码就不一一介绍了，大家可以参考苹果提供的有关文档：https://developer.apple.com/library/ios/samplecode/DownloadFont/Listings/DownloadFont_ViewController_m.html#//apple_ref/doc/uid/DTS40013404-DownloadFont_ViewController_m-DontLinkElementID_6

或者也可以参考唐巧先生的博客有比较详细的介绍：http://blog.devtang.com/blog/2013/08/11/ios-asian-font-download-introduction/

下面是我研究后的测试demo，提供给大家参考：

- (void)asynchronouslySetFontName:(NSString *)fontName{    UIFont* aFont = [UIFont fontWithName:fontName size:24];    // If the font is already downloaded    if (aFont && ([aFont.fontName compare:fontName] == NSOrderedSame || [aFont.familyName compare:fontName] == NSOrderedSame)) {        // Go ahead and display the sample text.        _fLabelView.text = @"欢迎查看我的博客";        _fLabelView.font = [UIFont fontWithName:fontName size:24];        return;    }        // Create a dictionary with the font's PostScript name.    NSMutableDictionary *attrs = [NSMutableDictionary dictionaryWithObjectsAndKeys:fontName, kCTFontNameAttribute, nil];        // Create a new font descriptor reference from the attributes dictionary.    CTFontDescriptorRef desc = CTFontDescriptorCreateWithAttributes((__bridge CFDictionaryRef)attrs);        NSMutableArray *descs = [NSMutableArray arrayWithCapacity:0];    [descs addObject:(__bridge id)desc];    CFRelease(desc);        __block BOOL errorDuringDownload = NO;        // Start processing the font descriptor..    // This function returns immediately, but can potentially take long time to process.    // The progress is notified via the callback block of CTFontDescriptorProgressHandler type.    // See CTFontDescriptor.h for the list of progress states and keys for progressParameter dictionary.    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(), ^ {                // Show an activity indicator                NSLog(@"Begin Matching");            });        } else if (state == kCTFontDescriptorMatchingDidFinish) {            dispatch_async( dispatch_get_main_queue(), ^ {                // Remove the activity indicator                                // Display the sample text for the newly downloaded font                _fLabelView.text = @"欢迎查看我的博客";                _fLabelView.font = [UIFont fontWithName:fontName size:24];                                // Log the font URL in the console                CTFontRef fontRef = CTFontCreateWithName((__bridge CFStringRef)fontName, 0., NULL);                CFStringRef fontURL = CTFontCopyAttribute(fontRef, kCTFontURLAttribute);                NSLog(@"%@", (__bridge NSURL*)(fontURL));                CFRelease(fontURL);                CFRelease(fontRef);                                if (!errorDuringDownload) {                    NSLog(@"%@ downloaded", fontName);                }            });        } else if (state == kCTFontDescriptorMatchingWillBeginDownloading) {            dispatch_async( dispatch_get_main_queue(), ^ {                // Show a progress bar                             NSLog(@"Begin Downloading");            });        } else if (state == kCTFontDescriptorMatchingDidFinishDownloading) {            dispatch_async( dispatch_get_main_queue(), ^ {                // Remove the progress bar                NSLog(@"Finish downloading");            });        } else if (state == kCTFontDescriptorMatchingDownloading) {            dispatch_async( dispatch_get_main_queue(), ^ {                // Use the progress bar to indicate the progress of the downloading                NSLog(@"Downloading %.0f%% complete", progressValue);            });        } else if (state == kCTFontDescriptorMatchingDidFailWithError) {            // An error has occurred.            // Get the error message            NSError *error = [(__bridge NSDictionary *)progressParameter objectForKey:(id)kCTFontDescriptorMatchingError];            if (error != nil) {                _errorMessage = [error description];            } else {                _errorMessage = @"ERROR MESSAGE IS NOT AVAILABLE!";            }            // Set our flag            errorDuringDownload = YES;                        dispatch_async( dispatch_get_main_queue(), ^ {                NSLog(@"Download error: %@", _errorMessage);            });        }        return (bool)YES;    });   }

只要在相应地方调用就可以了：

- (void)viewDidLoad {    [super viewDidLoad];    // Do any additional setup after loading the view, typically from a nib.    _fLabelView = [[UITextView alloc] initWithFrame:CGRectMake(50, 100, 250, 100)];    [self.view addSubview:_fLabelView];        [self asynchronouslySetFontName:@"HanziPenSC-W3"];    }

下面是运行后的结果：