ios-text paragraph style nsmutableparagraphstyle and Nsparagraphstyle use and some rich Text processing properties

In the process of development, we often encounter the problem of dynamic calculation of row height.

-(cgrectcgsize) size options: (nsstringdrawingoptions Options attributes: (nullable nsdictionary <nsstring *, id > *) Attributes Context: (nullable  Nsstringdrawingcontext *) Context ns_available ( Span class= "S3" >10_11, 7_0);

Is the Apple recommended calculation method, obviously encounter paragraph formatting problems, such as line spacing, indentation and other formatting requirements, attributes passed in the dictionary, including our set of fonts and formats, where nsparagraphstyleattributename is set paragraph style, Nsfontattributename is the setting font.

OK, take a look at the function of Nsparagraphstyleattributename.

[OBJC]View PlainCopy

2. Nsparagraphstyleattributename paragraph style (set first line, line spacing, alignment, etc.) see what you need and write
4. Nsmutableparagraphstyle *paragraphstyle = [[Nsmutableparagraphstyle alloc] init];
6. Paragraphstyle. linespacing = 10; Line spacing for fonts
8. Paragraphstyle. firstlineheadindent = 20. 0f; First line indent
10. Paragraphstyle. Alignment = nstextalignmentjustified; (justified) Text alignment: (left, middle, right, justified, natural)
12. Paragraphstyle. Linebreakmode = Nslinebreakbytruncatingtail; The end of the content with ... Way omitted ("... wxyz", "ABCD ...", "AB ... YZ ")
14. Paragraphstyle. headindent = 20; Overall indent (except for the first row)
16. Paragraphstyle. tailindent = 20; //    
18. Paragraphstyle. minimumlineheight = 10; Minimum row height
20. Paragraphstyle. maximumlineheight = 20; Maximum row height
22. Paragraphstyle. paragraphspacing = 15; spacing between segments and segments
24. Paragraphstyle. Paragraphspacingbefore = 22. 0f;  The Blank Space/* Distance between the bottom of the previous paragraph (or the end of its paragraphspacing, if any) and the top of this paragraph. */    
26. Paragraphstyle. basewritingdirection = nswritingdirectionlefttoright; The direction of writing from left to right (altogether?? Three types)
28. Paragraphstyle. lineheightmultiple = 15; /* Natural line height are multiplied by this factor (if positive) before being constrained by minimum and maximum line Hei Ght. */    
30. Paragraphstyle. hyphenationfactor = 1; Hyphenation properties in iOS, the only supported values are 0 and 1, respectively

OK, now it's easy to calculate a paragraph height, for example:

[OBJC]View PlainCopy

2. _descatt = [[nsmutableattributedstring alloc] initwithstring:_model. Desc];
4. Uifont *descfont = [Uifont pingfangsc_regular_withsize:12];
8. Nsmutableparagraphstyle *descstyle = [[Nsmutableparagraphstyle alloc]init];
10. [Descstyle setlinespacing:1]; Line spacing
14. Cgsize descsize = [_model. Desc Boundingrectwithsize:cgsizemake (w, maxfloat)
16. Options:nsstringdrawinguseslinefragmentorigin
18. Attributes:@{nsfontattributename:descfont,
20. Nsparagraphstyleattributename:d Escstyle}
22. context: nil]. Size;

In addition, several properties of rich Text processing are introduced:

[OBJC]View PlainCopy

2. Nsfontattributename setting font properties, default: Font: Helvetica (Neue) font Size: 12
4. Nsforegroundcolorattributenam set font color, value to Uicolor object, default value is black
6. Nsbackgroundcolorattributename set the region background color of the font, the value is Uicolor object, the default value is nil, transparent color
8. Nsligatureattributename sets the conjoined property, with a value of NSNumber object (integer), 0 for no conjoined character, and 1 for the default conjoined character
10. Nskernattributename set character spacing, value is NSNumber object (integer), positive spacing is widened, and negative spacing narrows
12. Nsstrikethroughstyleattributename set Strikethrough, value is NSNumber object (integer)
14. Nsstrikethroughcolorattributename set strikethrough color, value is Uicolor object, default value is black
16. Nsunderlinestyleattributename sets an underscore to a value of NSNumber object (integer), enumeration of values in constant Nsunderlinestyle, similar to strikethrough
18. Nsunderlinecolorattributename sets the underline color, the value is the Uicolor object, the default value is black
20. Nsstrokewidthattributename Sets the stroke width, takes a value of NSNumber object (integer), negative fill effect, positive hollow effect
22. Nsstrokecolorattributename fills part of the color, not the font color, and takes the value of the Uicolor object
24. Nsshadowattributename Set the Shadow property to a value of Nsshadow object
26. Nstexteffectattributename sets the text special effect, the value is the NSString object, currently only the plate printing effect is available:
28. Nsbaselineoffsetattributename set the baseline offset value to NSNumber (float), positive offset, negative bias
30. Nsobliquenessattributename set the Glyph tilt, value NSNumber (float), positive right, negative left
32. Nsexpansionattributename set text stretch properties, value nsnumber (float), positive values stretch text horizontally, negative values compress text horizontally
34. Nswritingdirectionattributename setting the direction of writing, writing from left to right or from right to left
36. Nsverticalglyphformattributename sets the text layout direction, takes a value of NSNumber object (integer), 0 for horizontal text, and 1 for vertical text
38. Nslinkattributename set the link properties, click on the browser to open the specified URL address
40. Nsattachmentattributename Set the text attachment, the value is the Nstextattachment object, commonly used in the text picture mixed row
42. Nsparagraphstyleattributename set the text paragraph layout format, the value is Nsparagraphstyle object

ios-text paragraph style nsmutableparagraphstyle and Nsparagraphstyle use and some rich Text processing properties