UIButton custom font vertical alignment

Question

A similar problem was discussed at Custom installed font not displayed correctly in UILabel. There was no solution given.

Here's the solution that worked for my custom font which had the same issue in UILabel, UIButton and such. The problem with the font turned out to be the fact that its ascender property was too small compared to the value of system fonts. Ascender is a vertical whitespace above font's characters. To fix your font you will have to download Apple Font Tool Suite command line utilities. Then take your font and do the following:

~$ ftxdumperfuser -t hhea -A d Bold.ttf

This will create Bold.hhea.xml. Open it with a text editor and increase the value of ascender attribute. You will have to experiment a little to find out the exact value that works best for you. In my case I changed it from 750 to 1200. Then run the utility again with the following command line to merge your changes back into the ttf file:

~$ ftxdumperfuser -t hhea -A f Bold.ttf

Then just use the resulting ttf font in your app.

OS X El Capitan

The Apple Font Tool Suite Installer doesn't work anymore on OSX El Capitan because of SIP because it tries to install the binary files into a protected directory. You have to manually extract ftxdumperfuser. First copy the pkg from the dmg to a local directory afterwards unpack the OS X Font Tools.pkg with

~$ xar -xf OS\ X\ Font\ Tools.pkg

Now navigate into the folder fontTools.pkg with

~$ cd fontTools.pkg/

Extract payload with

~$ cat Payload | gunzip -dc | cpio -i

Now the ftxdumperfuser binary is in your current folder. You could move it to /usr/local/bin/ so that you can use it in every folder inside of the terminal application with the following.

~$ mv ftxdumperfuser /usr/local/bin/

I solved the problem adjusting the top content (not the title!) inset.

For example: button.contentEdgeInsets = UIEdgeInsetsMake(10.0, 0.0, 0.0, 0.0);

Good luck!

Not sure if this will help as it may depend on your font, but it could be that your baseline is misaligned.

self.searchButton.titleLabel.baselineAdjustment = 
    UIBaselineAdjustmentAlignCenters;

I think this is the best answer. no playing with ascender, numberOfHMetrics etc... just import-export by Glyphs application and Job done. Thanks to this answer: https://stackoverflow.com/a/16798036/1207684

Late to the party, but as this issue hit me for the Nth time, I thought I'd post the simplest solution I've found: using Python FontTools.

1. Install Python 3 if it's not available on your system.

2. Install FontTools

   pip3 install fonttools

   FontTools include a TTX tool which enables conversion to and from XML.

3. Convert your font to .ttx in the same folder

   ttx myFontFile.otf

4. Make the necessary edits to .ttx and delete the .otf file as this will be replaced in the next step.

5. Convert the file back to .otf

   ttx myFontFile.ttx

---

Motivation: The solution by kolyuchi is incomplete, and even with this extended installation flow, running ftxdumperfuser resulted in an error on 10.15.2 Catalina.