[objc] UIButton에 NSAttributedString 적용
NSMutableAttributedString *attrStr = [[NSMutableAttributedString alloc] initWithString:@"ボタン"];
/* フォント */
[attrStr addAttribute:NSFontAttributeName
value:[UIFont fontWithName:@"ChalkboardSE-Regular" size:30.f]
range:NSMakeRange(0, attrStr.length)];
/* 文字色 */
[attrStr addAttribute:NSForegroundColorAttributeName
value:[UIColor cyanColor]
range:NSMakeRange(0, attrStr.length)];
// 中抜き文字の枠線の色、下線、カーニングを一度に指定
NSDictionary *attributes = @{NSStrokeColorAttributeName: [UIColor magentaColor],
NSUnderlineStyleAttributeName: @(NSUnderlineStyleSingle),
NSKernAttributeName: @1.5};
NSString *tStr = @"ボタン";
[attrStr addAttributes:attributes
range:[tStr rangeOfString:@"ボ"]];