Link with Selection Action for Help View toolbar is implemented.

This is similar to JDT Package Explorer's 'Link with Editor' Action. We
will refresh the Help View input based on selection if this Action is
enabled.

see #1874

Author: raghucssit

ua/org.eclipse.help.base/src/org/eclipse/help/internal/base/HelpBasePlugin.java

@@ -71,6 +71,16 @@ public String getDocumentMessage(boolean embedded) {
 		public boolean getDocumentMessageUsesLiveHelp(boolean embedded) {
 			return false;
 		}
+
+		@Override
+		public boolean isSyncSelection() {
+			return false;
+		}
+
+		@Override
+		public void setSyncSelection(boolean syncSel) {
+
+		}
 	};
 
 

ua/org.eclipse.help.base/src/org/eclipse/help/internal/base/IHelpActivitySupport.java

@@ -57,6 +57,10 @@ public interface IHelpActivitySupport {
 
 	public void setFilteringEnabled(boolean enabled);
 
+	public boolean isSyncSelection();
+
+	public void setSyncSelection(boolean syncSel);
+
 	public boolean isUserCanToggleFiltering();
 
 	/**

ua/org.eclipse.help.ui/icons/elcl16/synced.svg

@@ -21,6 +21,7 @@
 import org.eclipse.core.runtime.IProduct;
 import org.eclipse.core.runtime.Platform;
 import org.eclipse.core.runtime.preferences.IEclipsePreferences;
+import org.eclipse.core.runtime.preferences.IPreferencesService;
 import org.eclipse.core.runtime.preferences.InstanceScope;
 import org.eclipse.help.internal.HelpPlugin;
 import org.eclipse.help.internal.base.HelpBasePlugin;
@@ -42,9 +43,12 @@ public class HelpActivitySupport implements IHelpActivitySupport {
 	private static final String SHOW_DISABLED_ACTIVITIES_ON = "on"; //$NON-NLS-1$
 //	private static final String SHOW_DISABLED_ACTIVITIES_ALWAYS = "always"; //$NON-NLS-1$
 
+	private static final String PREF_KEY_SYNC_SEL = "syncSelection"; //$NON-NLS-1$
+
 	private final IWorkbenchActivitySupport activitySupport;
 	private boolean userCanToggleFiltering;
 	private boolean filteringEnabled;
+	private boolean syncSelection;
 	private final ActivityDescriptor activityDescriptor;
 
 	static class ActivityDescriptor {
@@ -122,8 +126,9 @@ public HelpActivitySupport(IWorkbench workbench) {
 		activitySupport = workbench.getActivitySupport();
 		activityDescriptor = new ActivityDescriptor();
 
+		IPreferencesService prefService = Platform.getPreferencesService();
 		String showDisabledActivities =
-			Platform.getPreferencesService().getString(HelpBasePlugin.PLUGIN_ID, PREF_KEY_SHOW_DISABLED_ACTIVITIES, "", null); //$NON-NLS-1$
+			prefService.getString(HelpBasePlugin.PLUGIN_ID, PREF_KEY_SHOW_DISABLED_ACTIVITIES, "", null); //$NON-NLS-1$
 		userCanToggleFiltering = SHOW_DISABLED_ACTIVITIES_OFF
 				.equalsIgnoreCase(showDisabledActivities)
 				|| SHOW_DISABLED_ACTIVITIES_ON
@@ -136,6 +141,8 @@ public HelpActivitySupport(IWorkbench workbench) {
 				|| SHOW_DISABLED_ACTIVITIES_NEVER
 						.equalsIgnoreCase(showDisabledActivities);
 		filteringEnabled = filteringEnabled && isWorkbenchFiltering();
+
+		syncSelection = prefService.getBoolean(HelpBasePlugin.PLUGIN_ID, PREF_KEY_SYNC_SEL, false, null);
 	}
 
 	@Override
@@ -162,6 +169,22 @@ public void setFilteringEnabled(boolean enabled) {
 		}
 	}
 
+	@Override
+	public boolean isSyncSelection() {
+		return syncSelection;
+	}
+
+	@Override
+	public void setSyncSelection(boolean syncSel) {
+		this.syncSelection = syncSel;
+		IEclipsePreferences prefs = InstanceScope.INSTANCE.getNode(HelpBasePlugin.PLUGIN_ID);
+		prefs.putBoolean(PREF_KEY_SYNC_SEL, syncSel);
+		try {
+			prefs.flush();
+		} catch (BackingStoreException e) {
+		}
+	}
+
 	@Override
 	public boolean isUserCanToggleFiltering() {
 		return userCanToggleFiltering;

ua/org.eclipse.help.ui/src/org/eclipse/help/ui/internal/HelpActivitySupport.java

@@ -55,6 +55,7 @@ public interface IHelpUIConstants {
 	public static final String IMAGE_CLOSE_HOT = "elcl16/close_hot.svg"; //$NON-NLS-1$
 	public static final String IMAGE_SYNC_TOC = "elcl16/synch_toc_nav.svg"; //$NON-NLS-1$
 	public static final String IMAGE_SHOW_ALL = "elcl16/show_all.svg"; //$NON-NLS-1$
+	public static final String IMAGE_SYNC_SEL = "elcl16/synced.svg"; //$NON-NLS-1$
 	public static final String IMAGE_DOC_OVR = "ovr16/doc_co.svg"; //$NON-NLS-1$
 	public static final String IMAGE_SCOPE_SET = "obj16/scopeset_obj.svg"; //$NON-NLS-1$
 	public static final String IMAGE_SEARCH_WIZ = "wizban/newsearch_wiz.svg"; //$NON-NLS-1$