Fix open maven subproject context menu

attempt to fix UI issue of not selectable sub context menu on some
configurations.

Lazy init logic will create the JPopupMenu only once now.

ide/projectui/src/org/netbeans/modules/project/ui/actions/OpenSubprojects.java

@@ -27,9 +27,12 @@
 import javax.swing.JPopupMenu;
 import org.netbeans.api.annotations.common.StaticResource;
 import org.netbeans.api.project.Project;
+import org.netbeans.api.project.ProjectInformation;
 import org.netbeans.api.project.ProjectUtils;
 import org.netbeans.modules.project.ui.OpenProjectList;
+
 import static org.netbeans.modules.project.ui.actions.Bundle.*;
+
 import org.netbeans.spi.project.ProjectContainerProvider;
 import org.netbeans.spi.project.SubprojectProvider;
 import org.openide.awt.ActionID;
@@ -137,8 +140,8 @@ private void openAllRequiredProjects(Node [] activatedNodes) {
 
     private class LazyMenu extends JMenu {
         private final Node[] activatedNodes;
-        boolean initialized; // create only once, prevents recreating items when user repeatedly expends and collapses the menu
-        private Set<? extends Project> subProjects;
+        private boolean menuCreated; // create only once, prevents recreating items when user repeatedly expends and collapses the menu
+        private volatile Set<? extends Project> subProjects;
 
         @NbBundle.Messages("LBL_SubProjectPopupMenu_Initializing=Initializing...")
         private LazyMenu(Node[] nodes) {
@@ -147,25 +150,20 @@ private LazyMenu(Node[] nodes) {
             JMenuItem item = new JMenuItem(Bundle.LBL_SubProjectPopupMenu_Initializing());
             item.setEnabled(false);
             add(item);
-            RP.post(new Runnable() {
-                @Override
-                public void run() {
-                    getSubProjects();
-                }
-            });
+            RP.post(this::asyncFindSubProjects);
         }
 
         @Override
         public JPopupMenu getPopupMenu() {
-            if(initialized) {
+            if (!menuCreated && subProjects != null) {
                 createSubMenu();
             }
             return super.getPopupMenu(); 
         }
 
         private void createSubMenu() {
             removeAll();
-            if(subProjects != null && !subProjects.isEmpty()) {
+            if (!subProjects.isEmpty()) {
                 super.getPopupMenu().setLayout(new VerticalGridLayout());
                 final JMenuItem openAllProjectsItem = new JMenuItem(new AbstractAction() {
                     @Override
@@ -181,7 +179,7 @@ public void actionPerformed(ActionEvent e) {
                 nothingItem.setEnabled(false);
                 add(nothingItem);
             }
-            if(subProjects != null && !subProjects.isEmpty()) {
+            if (!subProjects.isEmpty()) {
                 for(final Project prjIter:subProjects) {
                     JMenuItem selectPrjAction = new JMenuItem(new AbstractAction() {
                         @Override
@@ -193,9 +191,10 @@ public void actionPerformed(ActionEvent e) {
                     add(selectPrjAction);
                 }
             }
+            menuCreated = true;
         }
 
-        private void getSubProjects() {
+        private void asyncFindSubProjects() {
             try {
                 if(activatedNodes != null) {
                     for( int i = 0; i < activatedNodes.length; i++ ) {
@@ -214,7 +213,15 @@ private void getSubProjects() {
                     }
                 }
             } finally {
-                initialized = true;
+                if (subProjects == null) {
+                    subProjects = Set.of();
+                } else {
+                    // trigger project name query tasks
+                    // without this, the first call to getDisplayName() will likely return a project path fallback
+                    for (Project project : subProjects) {
+                        ProjectUtils.getInformation(project).getDisplayName();
+                    }
+                }
             }
         }
     }