Fix context menu UX: show it on right-click no matter what was the selection

Previously popup menu was not shown if the tree node was not selected.

Author: vlsi

src/core/src/main/java/org/apache/jmeter/gui/GuiPackage.java

@@ -633,10 +633,9 @@ public void displayPopUp(Component invoker, MouseEvent e, JPopupMenu popup) {
         if (popup != null) {
             log.debug("Showing pop up for {} at x,y = {},{}", invoker, e.getX(), e.getY());
 
-            popup.pack();
+            // Enforce heavyweight popup to show shadows on macOS
+            popup.setLightWeightPopupEnabled(false);
             popup.show(invoker, e.getX(), e.getY());
-            popup.setVisible(true);
-            popup.requestFocusInWindow();
         }
     }
 

src/core/src/main/java/org/apache/jmeter/gui/tree/JMeterTreeListener.java

@@ -27,6 +27,7 @@
 
 import javax.swing.JPopupMenu;
 import javax.swing.JTree;
+import javax.swing.SwingUtilities;
 import javax.swing.event.TreeSelectionEvent;
 import javax.swing.event.TreeSelectionListener;
 import javax.swing.tree.TreePath;
@@ -154,7 +155,6 @@ public void mouseClicked(MouseEvent ev) {
 
     @Override
     public void mouseReleased(MouseEvent e) {
-        GuiPackage.getInstance().getMainFrame().repaint();
     }
 
     @Override
@@ -234,6 +234,10 @@ private boolean isRightClick(MouseEvent e) {
 
     private void displayPopUp(MouseEvent e) {
         JPopupMenu pop = getCurrentNode().createPopupMenu();
-        GuiPackage.getInstance().displayPopUp(e, pop);
+        // invokeLater ensures popup does not disappear when user right-clicks an inactive node
+        // In other words: right-click different nodes and verify if menu is shown every time.
+        // invokeLater seems to be required as long as tree.requestFocusInWindow(); is used
+        // in valueChanged
+        SwingUtilities.invokeLater(() -> GuiPackage.getInstance().displayPopUp(e, pop));
     }
 }

xdocs/changes.xml

@@ -80,6 +80,9 @@ For instance, <code>While Contoller</code> is disabled in the following tree, so
 are gray. It is purely a UI change, and the behavior is not altered.
 </p>
 <figure width="223" height="256" image="changes/5.3/disabled_subtree.png">While controller is disabled, so its children are gray</figure>
+
+<p>Tree context menu is shown even in case the node selection is changed. Previously
+    the popup did disappear and it was required to select a node first and only then launch popup.</p>
 <!--
 <ch_title>Functions</ch_title>
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