iOS/OS X - Justified Alignment on LAST LINE of text - ios

I'm working on an app where I need all lines of text to be Justified alignment. The app will display 2 lines of text over the top of an image, creating an Advert like feeling to the picture. The problem is that both these lines of text need to be justified, but the 2nd line of text will never be justified. Or if I draw both lines separately then neither will be justified.
If you specify kCTJustifiedTextAlignment in CoreText or NSJustifiedTextAlignment on NSTextField/View all but the last line of text are justified. The last line is aligned naturally.
Is there a way to force the final line of a textfield or textview to be justified, so fill the width of the view?
I've thought about using CTLine to draw each line separately, and specifying something on those to make all of them justified, but I'm not sure how to go about that either.
Thanks

Thanks to omz's comment I stumbled across CTLineCreateJustifiedLine, which gives me just what I wanted. I'd still be interested if someone has a solution using a Cocoa Control (NSTextView), but i'd be surprised if there was anything tbh.
CTLineRef line = CTLineCreateWithAttributedString((__bridge CFAttributedStringRef)attString);
line = CTLineCreateJustifiedLine(line, 1.0, dirtyRect.size.width);
CTLineDraw(line, context);
CFRelease(line);

Related

How to align two UILabels on the Y axis of the center of the first line of text

please see the image below for two examples of what is to be achived
the alignment should be on the Center Y of the first lines of each UILabels and should work regardless of font size or font. currently we have implemented this with different constraints to the top of the super view for different font and font size combinations.
the constraint to align the center of the two UILabels does not work since the text of the second UILabel is not fixed and can have several lines.
also the text is dynamic, so it is not known where the text will wrap to create the first line, thus it cannot be shown in an one line UILabel with the rest of the text in another one below.
currently this is implemented using UIKit, but if there is an easy solution in SwiftUI we can put these two labels in a SwiftUI component. so a SwiftUI solution would also be welcomed.
Your comments said "it should be on the glyphs" ... but, without additional information, my guess is that "real world" usage would not really need that level of precision.
For example:
While the glyphs are not perfectly center-Y aligned, it seems unlikely you'd run into a case where the first line of the "rightLabel" is " ' " ' " or . , . , ..
This layout can be easily done with only a few constraints - no need to do any calculations:
The "Positioning" label would, of course, be set .hidden = true so it would never be seen.
If you really, really want glyph-precision, you'll need to calculate
the Glyph bounding box for the left-label
the Glyph bounding box for first line of the right-label
calculate the "character box" offsets to align the Glyph Y-centers
and then position the two labels accordingly, or use Core Text to draw the text (instead of using UILabel).
Probably more work than necessary -- unless your actual use-case demands it.
That's an interesting problem! You can try using the centerYAnchor for the label on the left, and the firstBaselineAnchor for the label on the right... that will align the center Y with the text baseline, which isn't quite what you want.
To find the correct offset to apply, you can use the information from UIFont about the size of the characters. I'd probably start with capHeight * 0.5 and see if that looks or feels right. Something like:
leftLabel.centerYAnchor.constraint(equalTo: rightLabel.firstBaseLineAnchor, constant: rightFont.capHeight * 0.5)
This is a more difficult problem in SwiftUI, I think, because resolved font metrics aren't directly available to you.

NSAttributedString: Strikethrough text with replacement text above it

I am trying to draw an NSAttributedString (actually, a constructed NSMutableAttributedString) where the "original" text has been struck and replacement text inserted above it (I'm trying to replicate the look/feel of an Ancient Greek manuscript).
My technique is a combination of NSBaselineOffsetAttributeName with NSKernAttributeName, but it appears that using a negative value for NSKernAttributeName "wipes away" the strikethrough of the text, even if the characters don't overlap.
If I put an extra space after the "A" character (in the original text), the "A" gets the strikethrough, but the "EI" is also offset to the right. So, it appears that the offset/kerning of the "EI" text affects how much of the strikethrough actually occurs.
Here's what I'd like to reproduce (I don't care about the angle; it's not about a picture-perfect reproduction; just the gist):
Here's what is currently happening:
This is when I add an extra space after the strikethrough:
So, the only other thing I can think of would be to render a separate NSAttributedString in the correct place, separate from the current one, but I have no idea how to calculate the location of a specific character in an NSAttributedString when it's drawn. I'm drawing to a PDF, not to any on-screen control like a UILabel. Alternatively, I could draw the "strikethrough" myself as a line, but that seems to still require knowing the coordinates for the text in question, which is calculated on-the-fly, and I hope to use this method to reproduce a large sample of ancient texts, which means doing it by hand just isn't a good answer here.
Anything I'm missing, or any out-of-the-box ideas to try?

howto draw a text with alignment centered in simpliest way. (ios , swift)

I would like to draw a text in my custom view at point X,Y with center allignment. In case the text would be "SUGUS", I expect to have the Character G at Point X,Y.
I tried several things with NSString.drawinRect(), where I have to provide the width of the text, which has to be measured first depending on the Fonttype. It worked, but for me thats not a straightforward solution.
I purposely did not add code here, because a first try with code was misleading and I hope someone can help me with a clean simple solution ?

Line fill for UITextView?

Is there a property that will apply the proper character spacing to have all the text on each line in an NSAttributedString butt up against the bounds like in a book, (including the final line which I know isn't done in books)? I know kerning can be adjusted, but that won't dynamically adjust on a per line basis. Any help would be appreciated. Also NSTextAlignmentJustified and NSTextAlignmentNatural get close, but won't apply the effect to the last line of text.
The only option is to use NSTextAlignmentJustified. Last line is never justified, because NSTextAlignmentJustified refers to Left Justification mode, as it is the standard case.
For more information you can take a look at Typographic Alignment on wikipedia : http://en.wikipedia.org/wiki/Typographic_alignment

Align UITextView Right and Left.

I have UITextView, which is left aligned.
When last word does not fit on current line it goes to next line leaving spaces on end of line.
which does not give good look and feel.
So, what I want that if words of particular line feels the spaces left at end.
i.e. Spaces between two words can dynamically varies.
Here I am giving example of Scenario:
The width of text view,never put off until (here tomorrow does not fit,so it goes to next line leaving spaces).
Tomorrow what you can avoid all together.
So, problem is it does look good.
What I want is:
The width of text view never put off, until (varying spaces shown by)
tomorrow -what -you -can
avoid --all -- together.
Thanks in Advance.
There is no setting for justified aligment for text you only have center, left and right. If you want justified aligment where every line has the same amount of characters or something like that you can format the text entered to have carriage returns after x amount of characters or words, or something like that.

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