I want to know how to dynamically load font files at runtime?

[nehonpa]

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Version of Dear PyGui

Version: 1.11 Operating System: Windows 11

My Issue/Question

I want to know how to dynamically load font files at runtime, such as allowing me to freely choose to load new font files and then preview the newly loaded fonts. By the way, I started using a font as the default font.

To Reproduce

Steps to reproduce the behavior:

1. Go to '...'
2. Click on '....'
3. Scroll down to '....'
4. See error

Expected behavior

A clear and concise description of what you expected to happen.

Screenshots/Video

XXX (you can drag files here)

Standalone, minimal, complete and verifiable example

# Here's some code anyone can copy and paste to reproduce your issue
import dearpygui.dearpygui as dpg

dpg.create_context()
dpg.create_viewport()
dpg.setup_dearpygui()

with dpg.window(label="tutorial"):
    dpg.add_button(label="Press me")
    dpg.add_input_text('font_file',default_value="path/", width=129)
    dpg.add_input_int(label='px', tag='size',default_value=20, width=129)
    with dpg.child_window(tag="window"):pass
def change():
    font = dpg.get_value('font_file')
            size = dpg.get_value('size')
            __font_tag = f"{font}, {size}"
            print(self.__font_tag)
            with dpg.font_registry():
                with dpg.font(f"./font_data/fonts/{font}", size,tag=__font_tag):
                    dpg.add_font_range_hint(dpg.mvFontRangeHint_Chinese_Full)
                    dpg.add_font_range_hint(dpg.mvFontRangeHint_Chinese_Simplified_Common)
                    dpg.add_font_range_hint(dpg.mvFontRangeHint_Japanese)
                    dpg.add_font_range_hint(dpg.mvFontRangeHint_Cyrillic)
                    dpg.add_font_range_hint(dpg.mvFontRangeHint_Korean)
                    dpg.add_font_range_hint(dpg.mvFontRangeHint_Thai)
                    dpg.add_font_range_hint(dpg.mvFontRangeHint_Vietnamese)
            txt_list = ["text the font","测试文本"]
            for i in txt_list:
                f = dpg.add_text(i,parent='window',tag=i)
                dpg.bind_item_font(f,__font_tag)

dpg.show_viewport()
dpg.start_dearpygui()
dpg.destroy_context()

[fabriciochamon]

not using font hints, but here's a simple example for a font viewer that might help ?

import dearpygui.dearpygui as dpg

dpg.create_context()
dpg.create_viewport(title='Font viewer example', width=600, height=400)
dpg.add_font_registry(tag='font_reg')

current_font_name = None
available_font_sizes = [14, 50, 90]

def add_font(sender, app_data):
    global current_font_name, available_font_sizes

    # get font name and path
    font = app_data['file_path_name']
    font_name = app_data['file_name']
    current_font_name = font_name
    dpg.set_value('font_path', font)

    # add to font registry, in multiple sizes as in "available_font_sizes"
    added_fonts = []
    for size in available_font_sizes:
        font_tag = f'{font_name} : {size}'
        if not dpg.does_item_exist(font_tag):
            dpg.add_font(file=font, tag=font_tag, size=size, parent='font_reg')
        added_fonts.append(font_tag)

    # set sample text
    sample_text = dpg.get_value('sample_text')
    size_index = dpg.get_value('font_size')-1
    dpg.bind_item_font('sample_text_with_chosen_font', added_fonts[size_index])    
    dpg.set_value('sample_text_with_chosen_font', sample_text)

def change_font_size(sender, app_data):
    global current_font_name, available_font_sizes
    size = available_font_sizes[dpg.get_value('font_size')-1]
    font_tag = f'{current_font_name} : {size}'
    dpg.bind_item_font('sample_text_with_chosen_font', font_tag)
    dpg.set_value('size_value', f'{size} px')

def change_sample_text(sender, app_data):
    sample_text = dpg.get_value('sample_text')
    dpg.set_value('sample_text_with_chosen_font', sample_text)

with dpg.window(tag='main_window', label='Font viewer'):

    # create font chooser dialog as hidden
    with dpg.file_dialog(tag='font_dialog', label='Choose font', width=400, height=200, show=False, callback=add_font):
        dpg.add_file_extension("Font files (*.ttf *.otf}{.ttf,.otf}")
        
    # choose font file
    with dpg.group(horizontal=True):
        dpg.add_text('Font:')
        dpg.add_input_text(tag='font_path')    
        dpg.add_button(label='Choose...', callback=lambda:dpg.show_item('font_dialog'))

    # set font size
    with dpg.group(horizontal=True):
        dpg.add_text('Size:')
        dpg.add_slider_int(tag='font_size', default_value=int(len(available_font_sizes)/2), min_value=1, max_value=len(available_font_sizes), callback=change_font_size)
        dpg.add_text(f'{available_font_sizes[dpg.get_value("font_size")-1]} px', tag='size_value')
    
    # sample text to preview font
    dpg.add_separator()
    with dpg.group(horizontal=True):
        dpg.add_text('Sample text:')
        dpg.add_input_text(tag='sample_text', default_value='My Text!', callback=change_sample_text)
    dpg.add_text(tag='sample_text_with_chosen_font')

dpg.setup_dearpygui()
dpg.show_viewport()
dpg.set_primary_window('main_window', True)
dpg.start_dearpygui()
dpg.destroy_context()

[nehonpa]

Thank you for your suggestion, but unfortunately, just tested it and it worked when I didn't set the initial font. Once I do set the initial font, it will crash again.