Use system colors as default for selection color

The system selection/highlight color is set as default color for the viewer selection in Eclipse. This color setting can be overwritten by the user via the color preferences.

Author: Christopher-Hermann

bundles/org.eclipse.ui.themes/css/dark/e4-dark_preferencestyle.css

@@ -65,10 +65,6 @@ IEclipsePreferences#org-eclipse-ui-workbench:org-eclipse-ui-themes { /* pseudo a
 		'org.eclipse.ui.workbench.FORM_HEADING_ERROR_COLOR=255,110,110'
 		'org.eclipse.ui.workbench.FORM_HEADING_WARNING_COLOR=255,200,0'
 		'org.eclipse.ui.workbench.FORM_HEADING_INFO_COLOR=170,170,170'
-		'org.eclipse.ui.workbench.SELECTED_CELL_FOREGROUND=255,255,255'
-		'org.eclipse.ui.workbench.SELECTED_CELL_BACKGROUND=0,90,210'
-		'org.eclipse.ui.workbench.SELECTED_CELL_FOREGROUND_NO_FOCUS=227,227,227'
-		'org.eclipse.ui.workbench.SELECTED_CELL_BACKGROUND_NO_FOCUS=70,70,70'
 		'ERROR_COLOR=247,68,117'
 		'HYPERLINK_COLOR=111,197,238'
 		'INCOMING_COLOR=31,179,235'

bundles/org.eclipse.ui.workbench/Eclipse UI/org/eclipse/ui/internal/themes/ColumnViewerSelectionColorFactory.java

@@ -0,0 +1,49 @@
+package org.eclipse.ui.internal.themes;
+
+import java.util.Hashtable;
+import org.eclipse.core.runtime.IConfigurationElement;
+import org.eclipse.core.runtime.IExecutableExtension;
+import org.eclipse.swt.SWT;
+import org.eclipse.swt.graphics.RGB;
+import org.eclipse.swt.widgets.Display;
+import org.eclipse.ui.themes.IColorFactory;
+
+/**
+ * The factory to provide the default colors for viewer selections. The default
+ * color is based on the system color for the title, which is the actual
+ * highlight color. The color can be overwritten via the color preferences.
+ *
+ * @since 3.5
+ *
+ */
+public class ColumnViewerSelectionColorFactory implements IColorFactory, IExecutableExtension {
+
+	private String color = null;
+
+	@Override
+	public RGB createColor() {
+		if ("SELECTED_CELL_BACKGROUND".equals(color)) { //$NON-NLS-1$
+			return Display.getDefault().getSystemColor(SWT.COLOR_TITLE_BACKGROUND).getRGB();
+
+		} else if ("SELECTED_CELL_FOREGROUND".equals(color)) { //$NON-NLS-1$
+			return Display.getDefault().getSystemColor(SWT.COLOR_TITLE_FOREGROUND).getRGB();
+
+		} else if ("SELECTED_CELL_BACKGROUND_NO_FOCUS".equals(color)) { //$NON-NLS-1$
+			return Display.getDefault().getSystemColor(SWT.COLOR_TITLE_INACTIVE_BACKGROUND).getRGB();
+
+		} else if ("SELECTED_CELL_FOREGROUND_NO_FOCUS".equals(color)) { //$NON-NLS-1$
+			return Display.getDefault().getSystemColor(SWT.COLOR_TITLE_INACTIVE_FOREGROUND).getRGB();
+
+		} else {
+			return null;
+		}
+	}
+
+	@Override
+	public void setInitializationData(IConfigurationElement config, String propertyName, Object data) {
+		if (data instanceof Hashtable table) {
+			this.color = (String) table.get("color"); //$NON-NLS-1$
+		}
+	}
+
+}

bundles/org.eclipse.ui/plugin.xml

@@ -2055,44 +2055,72 @@
          </description>
       </colorDefinition>
       <colorDefinition
+            categoryId="org.eclipse.ui.workbenchMisc"
             id="org.eclipse.ui.workbench.SELECTED_CELL_FOREGROUND"
             isEditable="true"
-            categoryId="org.eclipse.ui.workbenchMisc"
-            label="%Color.selectedCellForeground"
-            value="255,255,255">
+            label="%Color.selectedCellForeground">
          <description>
             %Color.selectedCellForegroundDesc
          </description>
+         <colorFactory
+               class="org.eclipse.ui.internal.themes.ColumnViewerSelectionColorFactory"
+               plugin="org.eclipse.ui">
+            <parameter
+                  name="color"
+                  value="SELECTED_CELL_FOREGROUND">
+            </parameter>
+         </colorFactory>
       </colorDefinition>
       <colorDefinition
+            categoryId="org.eclipse.ui.workbenchMisc"
             id="org.eclipse.ui.workbench.SELECTED_CELL_BACKGROUND"
             isEditable="true"
-            categoryId="org.eclipse.ui.workbenchMisc"
-            label="%Color.selectedCellBackground"
-            value="0,90,210">
+            label="%Color.selectedCellBackground">
          <description>
             %Color.selectedCellBackgroundDesc
          </description>
+         <colorFactory
+               class="org.eclipse.ui.internal.themes.ColumnViewerSelectionColorFactory"
+               plugin="org.eclipse.ui">
+            <parameter
+                  name="color"
+                  value="SELECTED_CELL_BACKGROUND">
+            </parameter>
+         </colorFactory>
       </colorDefinition>
       <colorDefinition
             id="org.eclipse.ui.workbench.SELECTED_CELL_FOREGROUND_NO_FOCUS"
             isEditable="true"
             categoryId="org.eclipse.ui.workbenchMisc"
-            label="%Color.selectedCellForegroundNoFocus"
-            value="0,0,0">
+            label="%Color.selectedCellForegroundNoFocus">
          <description>
             %Color.selectedCellForegroundNoFocusDesc
          </description>
+         <colorFactory
+               class="org.eclipse.ui.internal.themes.ColumnViewerSelectionColorFactory"
+               plugin="org.eclipse.ui">
+            <parameter
+                  name="color"
+                  value="SELECTED_CELL_FOREGROUND_NO_FOCUS">
+            </parameter>
+         </colorFactory>
       </colorDefinition>
       <colorDefinition
             id="org.eclipse.ui.workbench.SELECTED_CELL_BACKGROUND_NO_FOCUS"
             isEditable="true"
             categoryId="org.eclipse.ui.workbenchMisc"
-            label="%Color.selectedCellBackgroundNoFocus"
-            value="220,220,220">
+            label="%Color.selectedCellBackgroundNoFocus">
          <description>
             %Color.selectedCellBackgroundNoFocusDesc
          </description>
+         <colorFactory
+               class="org.eclipse.ui.internal.themes.ColumnViewerSelectionColorFactory"
+               plugin="org.eclipse.ui">
+            <parameter
+                  name="color"
+                  value="SELECTED_CELL_BACKGROUND_NO_FOCUS">
+            </parameter>
+         </colorFactory>
       </colorDefinition>
    </extension>
    <extension