常用屬性
| key | value | 說明 |
|---|---|---|
| NSFontAttributeName | UIFont對象 | 字體大蟹硇：默認(rèn)Helvetica(Neue) 12 |
| NSParagraphStyleAttributeName | NSParagraphStyle對象 | 段落設(shè)置 |
| NSForegroundColorAttributeName | UIColor對象 | 字體顏色羔飞，默認(rèn)blackColor |
| NSBackgroundColorAttributeName | UIColor對象 | 背景色，默認(rèn)nil(無背景色) |
| NSLigatureAttributeName | 包含整數(shù)的NSNumber對象 | 連字符：默認(rèn)為1:默認(rèn)連接，0:不連接 |
| NSKernAttributeName | 包含浮點(diǎn)數(shù)的NSNumber對象 | 字符間距：默認(rèn)0（禁用） |
| NSTrackingAttributeName | 包含浮點(diǎn)數(shù)的NSNumber對象 | 修改默認(rèn)跟蹤的數(shù)量嫁艇。0表示禁用跟蹤攀芯。iOS14及以后系統(tǒng)可用。 |
| NSStrikethroughStyleAttributeName | 包含整數(shù)的NSNumber對象 | 刪除線：默認(rèn)0（無刪除線） |
| NSUnderlineStyleAttributeName | 包含整數(shù)的NSNumber對象 | 下劃線：默認(rèn)0（無下劃線） |
| NSStrokeColorAttributeName | UIColor對象 | 描邊顏色：nil（和文字的 foregroundColor一致） |
| NSStrokeWidthAttributeName | 包含浮點(diǎn)數(shù)的NSNumber對象 | 描邊寬度：正值空心描邊轨奄，負(fù)值實(shí)心描邊孟害，默認(rèn)0(不描邊) |
| NSShadowAttributeName | NSShadow對象 | 文本陰影,默認(rèn)為nil:無陰影 |
| NSTextEffectAttributeName | NSString對象 | 文字效果：默認(rèn)nil(沒有文字效果) |
| NSAttachmentAttributeName | NSTextAttachment對象 | 附件(常用作圖文混排) ：默認(rèn)nil(沒有附件) |
| NSLinkAttributeName | NSURL (優(yōu)先) 或 NSString對象 | 鏈接 |
| NSBaselineOffsetAttributeName | 包含浮點(diǎn)數(shù)的NSNumber對象 | 基線偏移量，默認(rèn)為0;正值向上偏移挪拟，負(fù)值向下偏移挨务，默認(rèn)0（不偏移） |
| NSUnderlineColorAttributeName | UIColor對象 | 下劃線顏色：默認(rèn)nil（和文字的 foregroundColor一致） |
| NSStrikethroughColorAttributeName | UIColor對象 | 刪除線顏色：默認(rèn) nil（和文字的 foregroundColor一致） |
| NSObliquenessAttributeName | 包含浮點(diǎn)數(shù)的NSNumber對象 | 字體傾斜 ：正值向右傾斜，負(fù)值向左傾斜玉组， 默認(rèn)0（不傾斜） |
| NSExpansionAttributeName | 包含浮點(diǎn)數(shù)的NSNumber對象 | 文本扁平化：正值橫向拉伸谎柄，負(fù)值橫向壓縮，默認(rèn)0（不拉伸） |
| NSWritingDirectionAttributeName | 存儲NSNumber類型的NSArray對象 | 書寫方向惯雳〕祝控制字符可以通過屏蔽NSWritingDirection和NSWritingDirectionFormatType值來獲得。 LRE: NSWritingDirectionLeftToRight\NSWritingDirectionEmbedding, RLE: NSWritingDirectionRightToLeft\NSWritingDirectionEmbedding, LRO: NSWritingDirectionLeftToRight\NSWritingDirectionOverride, RLO: NSWritingDirectionRightToLeft\NSWritingDirectionOverride |
| NSVerticalGlyphFormAttributeName | 包含整數(shù)的NSNumber對象 | 0表示水平文本石景。1表示垂直文本劈猿。如果沒有指定，它可以遵循更高級別的垂直方向設(shè)置潮孽。目前在iOS上揪荣，它總是水平的。任何其他值的行為是未定義的往史。 |
示例
NSLigatureAttributeName-連字符
UIFont *font = [UIFont fontWithName:@"futura" size:18];
NSString *text = @"逗號前面的我是一個沒有連字符樣式的fl仗颈，逗號后面的你是一個帶連字符樣式的fl（你看后半句的漢字連字符樣式好難體現(xiàn)出來哦)";
NSMutableDictionary *attributes = [NSMutableDictionary dictionary];
[attributes setObject:font forKey:NSFontAttributeName];
NSMutableAttributedString *att = [[NSMutableAttributedString alloc] initWithString:text attributes:attributes];
// 設(shè)置文本前半句無連字符效果
[att addAttribute:NSLigatureAttributeName value:[NSNumber numberWithInt:0] range:NSMakeRange(0, 19)];
// 設(shè)置文本后半句有連字符效果
[att addAttribute:NSLigatureAttributeName value:[NSNumber numberWithInt:1] range:NSMakeRange(19, text.length - 19)];
att.png
NSKernAttributeName - 字符間距
注意： 正值間距加寬，負(fù)值間距變窄椎例，0表示默認(rèn)效果
UIFont *font = [UIFont fontWithName:@"futura" size:18];
NSString *text = @"設(shè)置我的字間距為正值20有拉大效果挨决，中間的你是正常效果，設(shè)置他的字間距為負(fù)值-5有減少效果";
NSMutableDictionary *attributes = [NSMutableDictionary dictionary];
[attributes setObject:font forKey:NSFontAttributeName];
NSMutableAttributedString *att = [[NSMutableAttributedString alloc] initWithString:text attributes:attributes];
[att addAttribute:NSKernAttributeName value:@20 range:NSMakeRange(0, 18)];
[att addAttribute:NSKernAttributeName value:@(-5) range:NSMakeRange(28, text.length - 28)];
att.png
文字描邊
NSStrokeColorAttributeName - 描邊顏色
NSStrokeWidthAttributeName - 描邊寬度
- 描邊顏色要搭配非0的描邊寬度才會生效订歪，如果只設(shè)置了描邊顏色脖祈，描邊寬度為0，則沒有描邊效果
- 描邊寬度是正數(shù)刷晋，會對文字進(jìn)行描邊撒犀，但文字中心不填充（ 一種經(jīng)典的空心文本樣式是在該值為3.0）
- 描邊寬度是負(fù)數(shù)福压，會對文字進(jìn)行描邊，而且會同時對文字中心進(jìn)行填充（填充的顏色為文字本來的字體顏色）
UIFont *font = [UIFont fontWithName:@"futura" size:18];
NSString *text = @"只設(shè)置描邊顏色或舞，沒有設(shè)置描邊寬度（默認(rèn)為0）荆姆，沒有效果";
NSMutableDictionary *attributes = [NSMutableDictionary dictionary];
[attributes setObject:font forKey:NSFontAttributeName];
NSMutableAttributedString *att = [[NSMutableAttributedString alloc] initWithString:text attributes:attributes];
[att addAttribute:NSStrokeColorAttributeName value:[UIColor blueColor] range:NSMakeRange(0, text.length)];
att.png
UIFont *font = [UIFont fontWithName:@"futura" size:18];
NSString *text = @"將描邊寬度設(shè)置為正數(shù)3，無描邊顏色映凳，具有空心效果哦胆筒，此時描邊顏色默認(rèn)成字體本來的顏色！";
NSMutableDictionary *attributes = [NSMutableDictionary dictionary];
[attributes setObject:font forKey:NSFontAttributeName];
NSMutableAttributedString *att = [[NSMutableAttributedString alloc] initWithString:text attributes:attributes];
[att addAttribute:NSStrokeWidthAttributeName value:@(3) range:NSMakeRange(0, text.length)];
att.png
UIFont *font = [UIFont fontWithName:@"futura" size:18];
NSString *text = @"將描邊寬度設(shè)置為正數(shù)3诈豌，描邊顏色為紅色仆救，具有空心效果哦，因為正數(shù)不對文字內(nèi)部進(jìn)行填充矫渔！";
NSMutableDictionary *attributes = [NSMutableDictionary dictionary];
[attributes setObject:font forKey:NSFontAttributeName];
NSMutableAttributedString *att = [[NSMutableAttributedString alloc] initWithString:text attributes:attributes];
[att addAttribute:NSStrokeColorAttributeName value:[UIColor redColor] range:NSMakeRange(0, text.length)];
[att addAttribute:NSStrokeWidthAttributeName value:@(3) range:NSMakeRange(0, text.length)];
att.png
UIFont *font = [UIFont fontWithName:@"futura" size:18];
NSString *text = @"將描邊寬度設(shè)置為負(fù)數(shù)-3彤蔽，又設(shè)置描邊顏色，無空心效果庙洼，因為負(fù)數(shù)會對文字內(nèi)部進(jìn)行填充顿痪！";
NSMutableDictionary *attributes = [NSMutableDictionary dictionary];
[attributes setObject:font forKey:NSFontAttributeName];
NSMutableAttributedString *att = [[NSMutableAttributedString alloc] initWithString:text attributes:attributes];
[att addAttribute:NSStrokeColorAttributeName value:[UIColor purpleColor] range:NSMakeRange(0, text.length)];
[att addAttribute:NSStrokeWidthAttributeName value:@(-3) range:NSMakeRange(0, text.length)];
att.png
NSShadowAttributeName-陰影
UIFont *font = [UIFont fontWithName:@"futura" size:18];
NSString *text = @"一個有陰影的文本！";
NSMutableDictionary *attributes = [NSMutableDictionary dictionary];
[attributes setObject:font forKey:NSFontAttributeName];
NSMutableAttributedString *att = [[NSMutableAttributedString alloc] initWithString:text attributes:attributes];
// 創(chuàng)建NSShadow實(shí)例
NSShadow *shadow = [[NSShadow alloc] init];
shadow.shadowColor = [UIColor purpleColor];
shadow.shadowBlurRadius = 3.0;
shadow.shadowOffset = CGSizeMake(0, 0.8);
// 添加屬性
[att addAttribute:NSShadowAttributeName value:shadow range:NSMakeRange(0, text.length)];
att.png
NSTextEffectAttributeName-文字效果
UIFont *font = [UIFont fontWithName:@"futura" size:18];
NSString *text = @"我是沒有文字效果的油够，你是有文字效果的蚁袭！";
NSMutableDictionary *attributes = [NSMutableDictionary dictionary];
[attributes setObject:font forKey:NSFontAttributeName];
// [attributes setObject:[UIColor darkGrayColor] forKey:NSBackgroundColorAttributeName];
NSMutableAttributedString *att = [[NSMutableAttributedString alloc] initWithString:text attributes:attributes];
[att addAttribute:NSTextEffectAttributeName value:NSTextEffectLetterpressStyle range:NSMakeRange(10, text.length - 10)];
att.png
att.png
NSLinkAttributeName - 鏈接
注意：UILabel無法使用該屬性, 但UITextView 控件可以使用，所以下面關(guān)于 NSLinkAttributeName 屬性的代碼也是使用 UITextView 來測試的石咬。
// 注意：跳轉(zhuǎn)鏈接要實(shí)現(xiàn)UITextView的這個委托方法
- (BOOL)textView:(UITextView *)textView shouldInteractWithURL:(NSURL *)url inRange:(NSRange)characterRange {
return YES;
}
- (void)linkAttributeTest {
NSString *text = @"點(diǎn)我跳轉(zhuǎn)到百度哦揩悄！";
NSMutableAttributedString * attributeStr = [[NSMutableAttributedString alloc] initWithString:text];
NSURL *url = [NSURL URLWithString:@"https://www.baidu.com"];
[attributeStr addAttribute:NSLinkAttributeName value:url range:NSMakeRange(0, text.length)];
self.textView.attributedText = attributeStr;
}
NSBaselineOffsetAttributeName-基準(zhǔn)線
注意：正值向上偏移，負(fù)值向下偏移鬼悠，默認(rèn)0（不偏移）
UIFont *font = [UIFont fontWithName:@"Savoye Let" size:18];
NSString *text = @"負(fù)值向下偏移";
NSMutableDictionary *attributes = [NSMutableDictionary dictionary];
[attributes setObject:font forKey:NSFontAttributeName];
NSMutableAttributedString *att = [[NSMutableAttributedString alloc] initWithString:text attributes:attributes];
[att addAttribute:NSBaselineOffsetAttributeName value:@(-10) range:NSMakeRange(0, text.length)];
att.png
att.png
att.png
NSExpansionAttributeName -文本扁平化（橫向拉伸）
注意：正值橫向拉伸删性，負(fù)值橫向壓縮，默認(rèn)0（不拉伸）
UIFont *font = [UIFont fontWithName:@"Savoye Let" size:18];
NSString *text = @"正值橫向拉伸焕窝，無扁平效果蹬挺，負(fù)值橫向壓縮！";
NSMutableDictionary *attributes = [NSMutableDictionary dictionary];
[attributes setObject:font forKey:NSFontAttributeName];
NSMutableAttributedString *att = [[NSMutableAttributedString alloc] initWithString:text attributes:attributes];
[att addAttribute:NSExpansionAttributeName value:@(0.8) range:NSMakeRange(0, 7)];
[att addAttribute:NSExpansionAttributeName value:@(-0.8) range:NSMakeRange(13, text.length - 13)];
att.png
NSTrackingAttributeName
類似NSKernAttributeName袜啃。
UIFont *font = [UIFont fontWithName:@"Savoye Let" size:18];
NSString *text = @"NSTrackingAttributeName，NSTrackingAttributeName幸缕，NSTrackingAttributeName";
NSMutableDictionary *attributes = [NSMutableDictionary dictionary];
[attributes setObject:font forKey:NSFontAttributeName];
NSMutableAttributedString *att = [[NSMutableAttributedString alloc] initWithString:text attributes:attributes];
[att addAttribute:NSTrackingAttributeName value:@(8.8) range:NSMakeRange(0, 23)];
[att addAttribute:NSTrackingAttributeName value:@(-8.8) range:NSMakeRange(46, 23)];
att.png
段落設(shè)置
NSMutableParagraphStyle
| 屬性 | 說明 |
|---|---|
| lineSpacing | 行間距 |
| paragraphSpacing | 段落間距 |
| alignment | 對齊方式 |
| firstLineHeadIndent | 首行縮進(jìn) |
| headIndent | 整段縮進(jìn) |
| tailIndent | 右側(cè)縮進(jìn) |
| lineBreakMode | 截斷方式 |
| minimumLineHeight | 最小行高 |
| maximumLineHeight | 最大行高 |
| baseWritingDirection | 書寫方向 |
| lineHeightMultiple | 行間距倍數(shù) |
| paragraphSpacingBefore | 段首行空白空間 |
| hyphenationFactor | 連字屬性 在iOS群发，唯一支持的值分別為0和1 |
| tabStops | 制表符 |
| allowsDefaultTighteningForTruncation | 收縮字符間距允許截斷 |
UIFont *font = [UIFont fontWithName:@"Savoye Let" size:18];
NSString *text = @"段落\n右對齊\n行間距20";
NSMutableParagraphStyle *style = [[NSMutableParagraphStyle alloc]init];
style.lineBreakMode = NSLineBreakByWordWrapping;
style.alignment = NSTextAlignmentRight;
style.lineSpacing = 20;
NSMutableDictionary *attributes = [NSMutableDictionary dictionary];
[attributes setObject:style forKey:NSParagraphStyleAttributeName];
[attributes setObject:font forKey:NSFontAttributeName];
NSAttributedString *att = [[NSAttributedString alloc] initWithString:text attributes:attributes];
att.png
不同大小的字體對齊
默認(rèn)基線對齊。iOS UIFont簡介與文本行數(shù)判斷
居中原理.jpg
UIFont *font = [UIFont systemFontOfSize:21];
UIFont *font2 = [UIFont systemFontOfSize:14];
NSString *text = @"1??不同大小的字體底部對齊??樣式（默認(rèn)）\n2??不同大小的字體頂部對齊??樣式\n3??不同大小的字體中間對齊??樣式";
NSMutableDictionary *attributes = [NSMutableDictionary dictionary];
[attributes setObject:font forKey:NSFontAttributeName];
NSMutableAttributedString *att = [[NSMutableAttributedString alloc] initWithString:text attributes:attributes];
[att addAttribute:NSFontAttributeName value:font2 range:NSMakeRange(10, 6)];
[att addAttribute:NSForegroundColorAttributeName value:[UIColor redColor] range:NSMakeRange(10, 6)];
[att addAttribute:NSFontAttributeName value:font2 range:NSMakeRange(33, 6)];
[att addAttribute:NSForegroundColorAttributeName value:[UIColor blueColor] range:NSMakeRange(33, 6)];
[att addAttribute:NSBaselineOffsetAttributeName value:@(font.ascender - font2.ascender) range:NSMakeRange(33, 6)];
[att addAttribute:NSFontAttributeName value:font2 range:NSMakeRange(52, 6)];
[att addAttribute:NSForegroundColorAttributeName value:[UIColor redColor] range:NSMakeRange(52, 6)];
[att addAttribute:NSBaselineOffsetAttributeName value:@((font.lineHeight - font2.lineHeight)/2 + ((font.descender - font2.descender))) range:NSMakeRange(52, 6)];
att.png
圖片
圖片
UIFont *font = [UIFont systemFontOfSize:24];
NSString *text = @"富文本圖片";
NSMutableDictionary *attributes = [NSMutableDictionary dictionary];
[attributes setObject:font forKey:NSFontAttributeName];
[attributes setObject:[UIColor yellowColor] forKey:NSBackgroundColorAttributeName];
NSMutableAttributedString *att = [[NSMutableAttributedString alloc] initWithString:text attributes:attributes];
NSLog(@"純文字:%ld",att.length);
NSTextAttachment *attachment = [[NSTextAttachment alloc] init];
attachment.image = [UIImage imageNamed:@"1"];
attachment.bounds = CGRectMake(0,0,30,20);
[att appendAttributedString:[NSAttributedString attributedStringWithAttachment:attachment]];
NSLog(@"文字+圖片:%ld",att.length);
att.png
圖片長度
UIFont *font = [UIFont systemFontOfSize:24];
NSString *text = @"富文本圖片";
NSMutableDictionary *attributes = [NSMutableDictionary dictionary];
[attributes setObject:font forKey:NSFontAttributeName];
[attributes setObject:[UIColor yellowColor] forKey:NSBackgroundColorAttributeName];
NSMutableAttributedString *att = [[NSMutableAttributedString alloc] initWithString:text attributes:attributes];
NSLog(@"純文字:%ld",att.length);
NSTextAttachment *attachment = [[NSTextAttachment alloc] init];
attachment.image = nil;
attachment.bounds = CGRectMake(0,0,30,20);
[att appendAttributedString:[NSAttributedString attributedStringWithAttachment:attachment]];
NSLog(@"文字+圖片:%ld",att.length);
att.png
純文字:5
文字+圖片:6
圖片添加至NSTextAttachment生成富文本后发乔，占一個字節(jié)長度（無論圖片大小或是否存在）熟妓。
圖片對齊
NSTextAttachment默認(rèn)也是基線對齊，attachment.bounds的坐標(biāo)原點(diǎn)Y軸是和基線持平栏尚，是CoreGraphics的坐標(biāo)系起愈。
原理同上述文字對齊。
UIFont *font = [UIFont systemFontOfSize:24];
NSString *text = @"富文本圖片";
NSMutableDictionary *attributes = [NSMutableDictionary dictionary];
[attributes setObject:font forKey:NSFontAttributeName];
[attributes setObject:[UIColor yellowColor] forKey:NSBackgroundColorAttributeName];
NSMutableAttributedString *att = [[NSMutableAttributedString alloc] initWithString:text attributes:attributes];
NSLog(@"純文字:%ld",att.length);
NSTextAttachment *attachment = [[NSTextAttachment alloc] init];
attachment.image = [UIImage imageNamed:@"1"];
attachment.bounds = CGRectMake(0,0,30,20);
[att appendAttributedString:[NSAttributedString attributedStringWithAttachment:attachment]];
[att addAttribute:NSBaselineOffsetAttributeName value:@((font.lineHeight - 20)/2 + (font.descender)) range:NSMakeRange(5, 1)];
NSLog(@"文字+圖片:%ld",att.length);
att.png
UIFont *font = [UIFont systemFontOfSize:24];
NSString *text = @"文本\n富文本圖片\n文本";
NSMutableDictionary *attributes = [NSMutableDictionary dictionary];
[attributes setObject:font forKey:NSFontAttributeName];
[attributes setObject:[UIColor yellowColor] forKey:NSBackgroundColorAttributeName];
NSMutableAttributedString *att = [[NSMutableAttributedString alloc] initWithString:text attributes:attributes];
NSLog(@"純文字:%ld",att.length);
NSTextAttachment *attachment = [[NSTextAttachment alloc] init];
attachment.image = [UIImage imageNamed:@"1"];
attachment.bounds = CGRectMake(0,0,30,20);
NSAttributedString *textAtt = [NSAttributedString attributedStringWithAttachment:attachment];
[att insertAttributedString:textAtt atIndex:6];
[att addAttribute:NSBaselineOffsetAttributeName value:@((font.lineHeight - 20)/2 + (font.descender)) range:NSMakeRange(6, 1)];
NSLog(@"文字+圖片:%ld",att.length);
att.png
文字圖片間隔
NSKernAttributeName屬性對圖片與文字的間距設(shè)置不生效。
網(wǎng)絡(luò)圖片
判斷網(wǎng)絡(luò)圖片是否存在抬虽，不存在先試用占位圖官觅，開啟異步下載，下載完成后重新生成富文本替換阐污。
參考文檔
iOS富文本NSAttributedString垂直對齊
iOS--NSAttributedString超全屬性詳解及應(yīng)用（富文本休涤、圖文混排）
