feature: add a toggle button in Preference dialog to only use monospace font in code editor (#292)

src/Resources/Locales/en_US.axaml

@@ -360,6 +360,7 @@
   <x:String x:Key="Text.Preference.Appearance.DefaultFont" xml:space="preserve">Default Font</x:String>
   <x:String x:Key="Text.Preference.Appearance.DefaultFontSize" xml:space="preserve">Default Font Size</x:String>
   <x:String x:Key="Text.Preference.Appearance.MonospaceFont" xml:space="preserve">Monospace Font</x:String>
+  <x:String x:Key="Text.Preference.Appearance.OnlyUseMonoFontInEditor" xml:space="preserve">Only use monospace font in text editor</x:String>
   <x:String x:Key="Text.Preference.Appearance.Theme" xml:space="preserve">Theme</x:String>
   <x:String x:Key="Text.Preference.Appearance.ThemeOverrides" xml:space="preserve">Theme Overrides</x:String>
   <x:String x:Key="Text.Preference.General" xml:space="preserve">GENERAL</x:String>

src/Resources/Locales/zh_CN.axaml

@@ -363,6 +363,7 @@
   <x:String x:Key="Text.Preference.Appearance.DefaultFont" xml:space="preserve">缺省字体</x:String>
   <x:String x:Key="Text.Preference.Appearance.DefaultFontSize" xml:space="preserve">默认字体大小</x:String>
   <x:String x:Key="Text.Preference.Appearance.MonospaceFont" xml:space="preserve">等宽字体</x:String>
+  <x:String x:Key="Text.Preference.Appearance.OnlyUseMonoFontInEditor" xml:space="preserve">仅在文本编辑器中使用等宽字体</x:String>
   <x:String x:Key="Text.Preference.Appearance.Theme" xml:space="preserve">主题</x:String>
   <x:String x:Key="Text.Preference.Appearance.ThemeOverrides" xml:space="preserve">主题自定义</x:String>
   <x:String x:Key="Text.Preference.General" xml:space="preserve">通用配置</x:String>

src/Resources/Locales/zh_TW.axaml

@@ -363,6 +363,7 @@
   <x:String x:Key="Text.Preference.Appearance.DefaultFont" xml:space="preserve">預設字型</x:String>
   <x:String x:Key="Text.Preference.Appearance.DefaultFontSize" xml:space="preserve">預設字型大小</x:String>
   <x:String x:Key="Text.Preference.Appearance.MonospaceFont" xml:space="preserve">等寬字型</x:String>
+  <x:String x:Key="Text.Preference.Appearance.OnlyUseMonoFontInEditor" xml:space="preserve">僅在文字編輯器中使用等寬字體</x:String>
   <x:String x:Key="Text.Preference.Appearance.Theme" xml:space="preserve">主題</x:String>
   <x:String x:Key="Text.Preference.Appearance.ThemeOverrides" xml:space="preserve">主題自訂</x:String>
   <x:String x:Key="Text.Preference.General" xml:space="preserve">通用配置</x:String>

src/Resources/Styles.axaml

@@ -259,7 +259,7 @@
     <Setter Property="FontStyle" Value="Italic"/>
   </Style>
   <Style Selector="TextBlock.monospace, SelectableTextBlock.monospace">
-    <Setter Property="FontFamily" Value="{Binding Source={x:Static vm:Preference.Instance}, Path=MonospaceFont}"/>
+    <Setter Property="FontFamily" Value="{Binding Source={x:Static vm:Preference.Instance}, Path=PrimaryFont}"/>
   </Style>
   <Style Selector="TextBlock.group_header_label">
     <Setter Property="Foreground" Value="{DynamicResource Brush.FG2}"/>

src/ViewModels/Preference.cs

@@ -92,6 +92,22 @@ namespace SourceGit.ViewModels
             set => SetProperty(ref _monospaceFont, value);
         }
 
+        [JsonIgnore]
+        public FontFamily PrimaryFont
+        {
+            get => _onlyUseMonoFontInEditor ? _defaultFont : _monospaceFont;
+        }
+
+        public bool OnlyUseMonoFontInEditor
+        {
+            get => _onlyUseMonoFontInEditor;
+            set
+            {
+                if (SetProperty(ref _onlyUseMonoFontInEditor, value))
+                    OnPropertyChanged(nameof(PrimaryFont));
+            }
+        }
+
         public double DefaultFontSize
         {
             get => _defaultFontSize;
@@ -486,6 +502,7 @@ namespace SourceGit.ViewModels
         private string _themeOverrides = string.Empty;
         private FontFamily _defaultFont = null;
         private FontFamily _monospaceFont = null;
+        private bool _onlyUseMonoFontInEditor = false;
         private double _defaultFontSize = 13;
         private LayoutInfo _layout = new LayoutInfo();
 

src/Views/Preference.axaml

@@ -150,7 +150,7 @@
           <TabItem.Header>
             <TextBlock Classes="tab_header" Text="{DynamicResource Text.Preference.Appearance}"/>
           </TabItem.Header>
-          <Grid Margin="8" RowDefinitions="32,32,32,32,32" ColumnDefinitions="Auto,*">
+          <Grid Margin="8" RowDefinitions="32,32,32,32,32,32" ColumnDefinitions="Auto,*">
             <TextBlock Grid.Row="0" Grid.Column="0"
                        Text="{DynamicResource Text.Preference.Appearance.Theme}"
                        HorizontalAlignment="Right"
@@ -232,6 +232,10 @@
                 </Button>
               </TextBox.InnerRightContent>
             </TextBox>
+
+            <CheckBox Grid.Row="5" Grid.Column="1"
+                      Content="{DynamicResource Text.Preference.Appearance.OnlyUseMonoFontInEditor}"
+                      IsChecked="{Binding OnlyUseMonoFontInEditor, Mode=TwoWay}"/>
           </Grid>
         </TabItem>