[Preferences] Workaround for default font not retrieved from pluginCu…

…stomization file

If user has a pluginCustomization file set as follows a default font is not loaded by Eclipse's preferences

-pluginCustomization
custom.prefs

Pressing the "Default" button in Preferences will show the system font instead of the one in the pluginCustomization file

So manually load it from the pluginCustomization file if present

com.archimatetool.editor/src/com/archimatetool/editor/preferences/FontsPreferencePage.java

@@ -14,7 +14,6 @@
 import org.eclipse.e4.core.services.events.IEventBroker;
 import org.eclipse.jface.layout.GridDataFactory;
 import org.eclipse.jface.preference.PreferencePage;
-import org.eclipse.jface.resource.JFaceResources;
 import org.eclipse.jface.viewers.CellLabelProvider;
 import org.eclipse.jface.viewers.DoubleClickEvent;
 import org.eclipse.jface.viewers.IDoubleClickListener;
@@ -94,15 +93,27 @@ FontData getFontData() {
         }
 
         FontData getDefaultFontData() {
-            return getSystemFontData();
+            // Get default font that might be set in a pluginCustomization settings file
+            FontData fontData = ThemeUtils.getDefaultThemeFontData(fontDefinitionId);
+            return fontData != null ? fontData : getSystemFontData();
         }
 
         void performOK() {
             ThemeUtils.setCurrentThemeFont(fontDefinitionId, getFontData(), getSystemFontData());
         }
 
         FontData getSystemFontData() {
-            return JFaceResources.getDefaultFont().getFontData()[0];
+            return getShell().getDisplay().getSystemFont().getFontData()[0];
+        }
+
+        FontData getSafeFontData(String fontDetails) {
+            try {
+                return new FontData(fontDetails);
+            }
+            catch(Exception ex) {
+            }
+
+            return getSystemFontData();
         }
     }
 
@@ -165,16 +176,6 @@ void performOK() {
         FontData getSystemFontData() {
             return FontFactory.getDefaultViewOSFontData();
         }
-
-        FontData getSafeFontData(String fontDetails) {
-            try {
-                return new FontData(fontDetails);
-            }
-            catch(Exception ex) {
-            }
-
-            return getSystemFontData();
-        }
     }
 
     // Table

com.archimatetool.editor/src/com/archimatetool/editor/ui/ThemeUtils.java

@@ -5,13 +5,18 @@
  */
 package com.archimatetool.editor.ui;
 
+import java.io.File;
+import java.io.FileInputStream;
 import java.util.Objects;
+import java.util.Properties;
 
+import org.eclipse.core.runtime.Platform;
 import org.eclipse.core.runtime.preferences.IEclipsePreferences;
 import org.eclipse.core.runtime.preferences.InstanceScope;
 import org.eclipse.e4.core.contexts.IEclipseContext;
 import org.eclipse.e4.ui.css.swt.internal.theme.ThemeEngine;
 import org.eclipse.e4.ui.css.swt.theme.IThemeEngine;
+import org.eclipse.jface.preference.PreferenceConverter;
 import org.eclipse.jface.resource.FontRegistry;
 import org.eclipse.jface.resource.StringConverter;
 import org.eclipse.jface.util.IPropertyChangeListener;
@@ -298,6 +303,59 @@ public static Font getCurrentThemeFont(String fontDefinitionId) {
     private static FontRegistry getCurrentThemeFontRegistry() {
         return getThemeManager() != null ? getThemeManager().getCurrentTheme().getFontRegistry() : null;
     }
+
+    /**
+     * Get the default FontData value for a font definition or null
+     */
+    public static FontData getDefaultThemeFontData(String fontDefinitionId) {
+        // Eclipse over-writes any default font properties that are declared in the pluginCustomization file with the default font from the theme plug-in
+        // So we'll manually check that file first
+        try {
+            String prefsFile = null;
+
+            // Is there a "-pluginCustomization" argument with file name?
+            String[] args = Platform.getCommandLineArgs();
+            for(int i = 0; i < args.length; i++) {
+                if(args[i].equalsIgnoreCase("-pluginCustomization")) {
+                    if(args.length > i + 1) {
+                        prefsFile = args[i + 1];
+                        break;
+                    }
+                }
+            }            
+
+            // Yes, does the file exist?
+            if(prefsFile != null) {
+                File file = new File(prefsFile);
+                if(file.exists()) {
+                    // Open it as a properties file
+                    Properties props = new Properties();
+
+                    try(FileInputStream is = new FileInputStream(file)) {
+                        props.load(is);
+                    }
+
+                    // Get the font definition value, if any
+                    if(props.get("org.eclipse.ui.workbench/" + fontDefinitionId) instanceof String value) {
+                        return new FontData(value);
+                    }
+                }
+            }
+        }
+        catch(Exception ex) {
+            ex.printStackTrace();
+        }
+
+        // Else check the default value set in the theme plugin.xml file, if any
+        // If not set this will return the system font
+
+        FontDefinition fontDef = getThemeRegistry().findFont(fontDefinitionId);
+        if(fontDef == null) {
+            return null;
+        }
+
+        return PreferenceConverter.getDefaultFontData(PrefUtil.getInternalPreferenceStore(), createPreferenceKey(fontDef));
+    }
 
     /**
      * If theming is disabled set the font on the control from the fontDefinitionId