observer for adding new glyph to the font

RafaŁ Buchner

Hi,
I started to create a script that marks every added glyph with a specific colour.

To do that I used defcon observer font.addObserver(self, 'glyphOrderChangedCallback', 'Font.GlyphOrderChanged'), but somehow it doesn't work.

here is the method for that observer:

def glyphOrderChangedCallback(self, info):
        
        oldValue = info['oldValue']
        newValue = info['newValue']
        newGlyphNames = list(set(oldValue)-set(newValue))
        for name in newGlyphNames:
            self.font[name].colorMark = (1,0,0,1)

Maybe there is a better way to track the names of added glyph objects to the font?

Thanks in advance for any advice on how to make it work.

frederik

Keep a reference of the font in your class otherwise the observer will be gone after the script is finished.

Thats why the examples have an open window, so its the font and observers stays alive!

good luck

gferreira

@RafaŁ-Buchner haven’t tried to run the code, but there’s a typo: addObsever → addObserver

RafaŁ Buchner

@frederik said in observer for adding new glyph to the font:

font = CurrentFont()
defconFont = font.naked()
defconFont.dispatcher.addObsever(observer=self, methodName="glyphAdded", notification="Layer.GlyphAdded", observable=None)

class Test(object):
    def __init__(self, *args):
        font = CurrentFont()
        defconFont = font.naked()
        defconFont.dispatcher.addObsever(observer=self, methodName="glyphAdded", notification="Layer.GlyphAdded", observable=None)
    
    def glyphAdded(self, notification):
        print(notification)
Test()

Traceback (most recent call last):
  File "<untitled>", line 9, in <module>
  File "<untitled>", line 5, in __init__
AttributeError: 'NotificationCenter' object has no attribute 'addObsever'

Am I doing something wrong? I will check also Defcon source code, but I think it should work

frederik

There are defcon notifications for different actions see the source.

You can even set a global font wise observer (only with defcon objects)

font = CurrentFont()
defconFont = font.naked()
defconFont.dispatcher.addObsever(observer=self, methodName="glyphAdded", notification="Layer.GlyphAdded", observable=None)

when observable is None the notification center sends out a notification for each call, not only for the object its observing

good luck

gferreira

@RafaŁ-Buchner thanks for asking good questions here, it helps to improve the docs :)

this example is super valuable because it shows how to use RoboFont and defcon notifications together. thanks @frederik!

RafaŁ Buchner

@gferreira said in observer for adding new glyph to the font:

from vanilla import FloatingWindow
from mojo.events import addObserver, removeObserver

class NewGlyphMarker:
    
    def __init__(self):
        ### for debugging only
        self.w = FloatingWindow((200, 50), "mark new glyphs")
        self.w.bind("close", self.windowCloseCallback)
        self.w.open()
        ### end debugging
        self.font = None
        addObserver(self, "currentFontChanged", "fontBecameCurrent")        
        self.subscribeFont(CurrentFont())
    
    def __del__(self):
        self.unsubscribeFont()

    def windowCloseCallback(self, sender):
        removeObserver(self, "fontBecameCurrent")
        self.unsubscribeFont()
    
    def subscribeFont(self, font):
        self.unsubscribeFont()
        if font is not None:
            self.font = font
            self.font.addObserver(self, "glyphOrderChanged", "Font.GlyphOrderChanged")
        
    def unsubscribeFont(self):
        if self.font is not None:
            self.font.removeObserver(self, "Font.GlyphOrderChanged")
            self.font = None
            
    def currentFontChanged(self, notification):
        print('current font changed')
        # a robofont event notification
        self.subscribeFont(notification["font"])
        print(notification['font'])
        
    def glyphOrderChanged(self,  notification):
        print('glyph order changed')
        # a defcon notification
        font = notification.object
        font = RFont(font)

        oldGlyphOrder = notification.data['oldValue']
        newGlyphOrder = notification.data['newValue']
        newGlyphNames = list(set(newGlyphOrder) - set(oldGlyphOrder))
        for glyphName in newGlyphNames:
            self.font[glyphName].markColor = 1, 0, 0, 1

NewGlyphMarker()

Gustavo, You're the best !!! Big Thanks!!!

I messed up with getting data in the callback. Somehow nothing appeared in the output window (it is set to show every possible error).

gferreira

hi @RafaŁ-Buchner,

I gave it a try — this seems to work:

from vanilla import FloatingWindow
from mojo.events import addObserver, removeObserver

class NewGlyphMarker:
    
    def __init__(self):
        ### for debugging only
        self.w = FloatingWindow((200, 50), "mark new glyphs")
        self.w.bind("close", self.windowCloseCallback)
        self.w.open()
        ### end debugging
        self.font = None
        addObserver(self, "currentFontChanged", "fontBecameCurrent")        
        self.subscribeFont(CurrentFont())
    
    def __del__(self):
        self.unsubscribeFont()

    def windowCloseCallback(self, sender):
        removeObserver(self, "fontBecameCurrent")
        self.unsubscribeFont()
    
    def subscribeFont(self, font):
        self.unsubscribeFont()
        if font is not None:
            self.font = font
            self.font.addObserver(self, "glyphOrderChanged", "Font.GlyphOrderChanged")
        
    def unsubscribeFont(self):
        if self.font is not None:
            self.font.removeObserver(self, "Font.GlyphOrderChanged")
            self.font = None
            
    def currentFontChanged(self, notification):
        print('current font changed')
        # a robofont event notification
        self.subscribeFont(notification["font"])
        print(notification['font'])
        
    def glyphOrderChanged(self,  notification):
        print('glyph order changed')
        # a defcon notification
        font = notification.object
        font = RFont(font)

        oldGlyphOrder = notification.data['oldValue']
        newGlyphOrder = notification.data['newValue']
        newGlyphNames = list(set(newGlyphOrder) - set(oldGlyphOrder))
        for glyphName in newGlyphNames:
            self.font[glyphName].markColor = 1, 0, 0, 1

NewGlyphMarker()

(based on an older example script by @frederik)

I hope this does what you need… cheers!

SOLVED observer for adding new glyph to the font