Let user change default font size via preference

data/app.drey.Dialect.gschema.xml.in

@@ -28,8 +28,11 @@
         <!-- 0 = Ctrl+Enter | 1 = Enter -->
         <default>0</default>
     </key>
-    <key type="i" name="font-size">
-        <!-- 0 = System default font size -->
+    <key type="b" name="custom-default-font-size">
+        <default>false</default>
+    </key>
+    <key type="i" name="default-font-size">
+        <!-- 0 = User has never enabled custom default font size before -->
         <default>0</default>
     </key>
 

data/resources/about.blp

@@ -6,7 +6,7 @@ Adw.AboutWindow about {
   destroy-with-parent: true;
   application-name: _("Dialect");
   developer-name: _("The Dialect Authors");
-  copyright: _("Copyright 2020–⁠2022 The Dialect Authors");
+  copyright: _("Copyright 2020–⁠2023 The Dialect Authors");
   comments: _("A translation app for GNOME.");
   website: "https://github.com/dialect-app/dialect";
   issue-url: "https://github.com/dialect-app/dialect/issues";

data/resources/preferences.ui

@@ -121,6 +121,35 @@
             </child>
           </object>
         </child>
+        <child>
+          <object class="AdwPreferencesGroup">
+            <property name="title" translatable="yes">Appearance</property>
+            <child>
+              <object class="AdwExpanderRow" id="custom_default_font_size">
+                <property name="title" translatable="yes">Use Custom Font Size</property>
+                <property name="subtitle" translatable="yes">System font size is used otherwise.</property>
+                <property name="show-enable-switch">True</property>
+                <property name="enable-expansion">False</property>
+                <property name="expanded">True</property>
+                <child>
+                  <object class="AdwSpinRow" id="default_font_size">
+                    <property name="title" translatable="yes">Default Font Size</property>
+                    <property name="subtitle" translatable="yes">Changing the size via shortcuts does not overwrite this.</property>
+                    <property name="adjustment">
+                      <object class="GtkAdjustment">
+                        <property name="lower">6</property>
+                        <property name="upper">72</property>
+                        <property name="value">0</property>
+                        <property name="page-increment">10</property>
+                        <property name="step-increment">5</property>
+                      </object>
+                    </property>
+                  </object>
+                </child>
+              </object>
+            </child>
+          </object>
+        </child>
       </object>
     </child>
   </template>

dialect/main.py

@@ -159,7 +159,8 @@ def _on_about(self, _action, _param):
         about.props.version = VERSION
         about.props.developers = [
             "Mufeed Ali",
-            "Rafael Mardojai CM http://rafaelmardojai.com"
+            "Rafael Mardojai CM http://rafaelmardojai.com",
+            "Libretto"
         ]
 
         about.props.transient_for = self.window

dialect/preferences.py

@@ -1,5 +1,6 @@
 # Copyright 2020-2022 Mufeed Ali
 # Copyright 2020-2022 Rafael Mardojai CM
+# Copyright 2023 Libretto
 # SPDX-License-Identifier: GPL-3.0-or-later
 
 import os
@@ -27,6 +28,8 @@ class DialectPreferencesWindow(Adw.PreferencesWindow):
     translator_config = Gtk.Template.Child()
     tts = Gtk.Template.Child()
     tts_config = Gtk.Template.Child()
+    custom_default_font_size = Gtk.Template.Child()
+    default_font_size = Gtk.Template.Child()
 
     def __init__(self, parent, **kwargs):
         super().__init__(**kwargs)
@@ -42,6 +45,10 @@ def __init__(self, parent, **kwargs):
                             'selected', Gio.SettingsBindFlags.DEFAULT)
         Settings.get().bind('src-auto', self.src_auto, 'active',
                             Gio.SettingsBindFlags.DEFAULT)
+        Settings.get().bind('custom-default-font-size', self.custom_default_font_size, 'enable-expansion',
+                            Gio.SettingsBindFlags.DEFAULT)
+        Settings.get().bind('default-font-size', self.default_font_size, 'value',
+                            Gio.SettingsBindFlags.DEFAULT)
 
         self.translator_config.props.sensitive = False
         self.tts_config.props.sensitive = False
@@ -74,6 +81,10 @@ def __init__(self, parent, **kwargs):
         if os.getenv('XDG_CURRENT_DESKTOP') != 'GNOME':
             self.search_provider.props.visible = False
 
+        # Connect font size signals
+        self.custom_default_font_size.connect("notify::enable-expansion", self._custom_default_font_size_switch)
+        self.default_font_size.get_adjustment().connect("value-changed", self._change_current_font_size)
+
     @Gtk.Template.Callback()
     def is_not_true(self, _widget, boolean):
         """ Check if boolean is not true
@@ -121,3 +132,26 @@ def _provider_settings_tooltip(self, button, _pspec):
     def _on_translator_loading(self, window, _value):
         self.translator.props.sensitive = not window.translator_loading
         self.tts.props.sensitive = not window.translator_loading
+
+    def _custom_default_font_size_switch(self, row, _value):
+        """Called on self.custom_default_font_size::notify::enable-expansion signal"""
+        enabled = row.get_enable_expansion()
+        system_font_size = int(Gtk.Settings.get_default().get_property('gtk-font-name').split()[1])
+
+        if enabled:
+            if Settings.get().default_font_size == 0:
+                # User has never set custom size before
+                Settings.default_font_size = system_font_size
+                self.default_font_size.set_value(system_font_size)
+                self.parent.set_font_size(system_font_size)
+
+            else:
+                self.parent.set_font_size(Settings.get().default_font_size)
+        else:
+            self.parent.set_font_size(system_font_size)
+            self.custom_default_font_size.set_enable_expansion(False)
+
+    def _change_current_font_size(self, row):
+        """Called on self.default_font_size.get_adjustment()::value-changed signal"""
+        Settings.default_font_size = row.get_value()
+        self.parent.set_font_size(row.get_value())

dialect/settings.py

@@ -95,18 +95,22 @@ def translate_accel_value(self):
         return self.get_int('translate-accel')
 
     @property
-    def font_size(self):
-        """Return the user's preferred font size."""
-        value = self.get_int('font-size')
+    def custom_default_font_size(self):
+        """Return whether the user wants a custom default font size."""
+        return self.get_boolean('custom-default-font-size')
 
-        if value == 0:
-            return int(Gtk.Settings.get_default().get_property('gtk-font-name').split()[1])
-        else:
-            return value
+    @custom_default_font_size.setter
+    def default_font_size(self, enabled):
+        self.set_boolean('custom-default-font-size', enabled)
+
+    @property
+    def default_font_size(self):
+        """Return the user's preferred default font size."""
+        return self.get_int('default-font-size')
 
-    @font_size.setter
-    def font_size(self, size):
-        self.set_int('font-size', size)
+    @default_font_size.setter
+    def default_font_size(self, size):
+        self.set_int('default-font-size', size)
 
     @property
     def active_tts(self):

dialect/window.py

@@ -126,7 +126,10 @@ def __init__(self, text, langs, **kwargs):
 
         # Text buffers font size
         self.font_css_provider = Gtk.CssProvider()
-        self.font_size = Settings.get().font_size
+        if Settings.get().custom_default_font_size:
+            self.font_size = Settings.get().default_font_size
+        else:
+            self.font_size = int(Gtk.Settings.get_default().get_property('gtk-font-name').split()[1])
 
         # Setup window
         self.setup_actions()
@@ -800,7 +803,7 @@ def ui_font_size_inc(self, _action, _param):
 
     def ui_font_size_dec(self, _action, _param):
         new_size = self.font_size - 5
-        if new_size >= 5:
+        if new_size >= 6:
             self.set_font_size(new_size)
 
     def ui_copy(self, _action, _param):