设置行间距，计算带行间距的文本高度
设置行间距，计算带行间距的文本高度
//求有行间距的label高度
- (CGSize)boundingRectWithSize:(CGSize)size WithStr:(NSString*)string andFont:(UIFont *)font andLinespace:(CGFloat)space
{
NSMutableParagraphStyle *style = [[NSMutableParagraphStyle alloc]init];
[style setLineSpacing:space];
NSDictionary *attribute = @{NSFontAttributeName:font,NSParagraphStyleAttributeName:style};
CGSize retSize = [string boundingRectWithSize:size
options:\
NSStringDrawingTruncatesLastVisibleLine |
NSStringDrawingUsesLineFragmentOrigin |
NSStringDrawingUsesFontLeading
attributes:attribute
context:nil].size;
return retSize;
}
//设置label颜色，字体大小，行间距等
-(void)labelAtrributedSetBy:(UILabel*)label andIndex:(NSInteger)index andFont:(UIFont*)font andColor1:(UIColor*)color1 andColor2:(UIColor*)color2 andLength:(NSString*)str{
NSMutableAttributedString *AttributedStr = [[NSMutableAttributedString alloc]initWithString:label.text];
NSRange range = NSMakeRange(index,str.length);
NSMutableParagraphStyle *style = [[NSMutableParagraphStyle alloc]init];
[style setLineSpacing:4];
NSDictionary * adic = @{NSFontAttributeName :font,NSForegroundColorAttributeName:color1,NSParagraphStyleAttributeName:style};
[AttributedStr addAttributes:adic range:NSMakeRange(0, index)];
NSDictionary * bdic = @{NSFontAttributeName :font,NSForegroundColorAttributeName:color2,NSParagraphStyleAttributeName:style};
[AttributedStr addAttributes:bdic range:range];
label.attributedText = AttributedStr;
}
NSMutableAttributedString 富文本的一些属性1 @property(readwrite) CGFloat lineSpacing; //行间距 2 @property(readwrite) CGFloat paragraphSpacing; //段间距 3 @property(readwrite) NSTextAlignment alignment; //对齐方式 4 @property(readwrite) CGFloat firstLineHeadIndent; //首行缩紧 5 @property(readwrite) CGFloat headIndent; //除首行之外其他行缩进 6 @property(readwrite) CGFloat tailIndent; //每行容纳字符的宽度 7 @property(readwrite) NSLineBreakMode lineBreakMode; //换行方式 8 @property(readwrite) CGFloat minimumLineHeight; //最小行高 9 @property(readwrite) CGFloat maximumLineHeight; //最大行高 10 @property(readwrite) NSWritingDirection baseWritingDirection; //书写方式（NSWritingDirectionNatural，NSWritingDirectionLeftToRight，NSWritingDirectionRightToLeft）
11 @property(readwrite) CGFloat lineHeightMultiple;
12 @property(readwrite) CGFloat paragraphSpacingBefore;
13 @property(readwrite) float hyphenationFactor;
14 @property(readwrite,copy,NS_NONATOMIC_IOSONLY) NSArray *tabStops NS_AVAILABLE_IOS(7_0);
15 @property(readwrite,NS_NONATOMIC_IOSONLY) CGFloat defaultTabInterval NS_AVAILABLE_IOS(7_0);
NSForegroundColorAttributeName 文字前景色
NSBackgroundColorAttributeName 文字背景色
NSLigatureAttributeName 连体字（NSNumber @0:无连体，@1:默认连体，系统字体不包含对连体的支持）
NSUnderlineStyleAttributeName 下划线
NSStrokeColorAttributeName 只有在NSStrokeWidthAttributeName设置了值之后才有效（默认字体颜色和前景色一致，如果设置的颜色和前景色不一致则前景色无效）
NSStrokeWidthAttributeName 设置该属性之后字体变成空心字体，字体边线宽度为value设定的值
NSBaselineOffsetAttributeName 值为NSNumber类型，表明文字相对于其他文字基准线向上的偏移量
NSUnderlineColorAttributeName 值为UIColor类型，下划线颜色（只有在NSUnderlineStyleAttributeName的value为@1时有效）
NSUnderlineStyleAttributeName 值为NSNumber类型，下划线宽度（默认值为@0:下划线宽度为0——不现实下划线，@1:字符串有下划线）
方法2：KVC
// [self.writeTextField setValue:c4 forKeyPath:@"_placeholderLabel.textColor"];
// [self.writeTextField setValue:H7 forKeyPath:@"_placeholderLabel.font"];
// [self.writeTextField setValue:c3 forKeyPath:@"_placeholderLabel.backgroundColor"];
设置placeholder frame
//设置placeholderRect
- (void)drawPlaceholderInRect:(CGRect)rect{
UIColor *placeholderColor = [UIColor redColor];//设置颜色
[placeholderColor setFill];
// CGRect placeholderRect = CGRectMake(rect.origin.x+10, (rect.size.height- H7.pointSize)/2, rect.size.width, H7.pointSize);//设置距离
CGRect placeholderRect = rect;
NSMutableParagraphStyle *style = [[NSMutableParagraphStyle alloc] init];
style.lineBreakMode = NSLineBreakByTruncatingTail;
style.alignment = self.writeTextField.textAlignment;
NSDictionary *attr = @{NSParagraphStyleAttributeName:style,NSFontAttributeName:H3,NSForegroundColorAttributeName:c4};
[self.writeTextField.placeholder drawInRect:placeholderRect withAttributes:attr];
}