[Lib/Board manager] Workaround for unselectable dropdown

The on-hover UX should be slightly adapted to understand the needed action.
At least, using this method, the selected value does not disappear.

Author: facchinm

app/src/cc/arduino/contributions/libraries/ui/ContributedLibraryTableCellEditor.java

@@ -33,6 +33,7 @@
 
 import java.awt.Color;
 import java.awt.Component;
+import java.util.ArrayList;
 import java.util.Collections;
 import java.util.LinkedList;
 import java.util.List;
@@ -53,6 +54,8 @@
 @SuppressWarnings("serial")
 public class ContributedLibraryTableCellEditor extends InstallerTableCell {
 
+  private List<Component> cellList = new ArrayList<Component>();
+
   private ContributedLibraryReleases editorValue;
   private ContributedLibraryTableCellJPanel editorCell;
 
@@ -67,6 +70,10 @@ public Component getTableCellEditorComponent(JTable table, Object value,
                                                int column) {
     editorValue = (ContributedLibraryReleases) value;
 
+    if (cellList.size() > row && cellList.get(row) != null) {
+      return cellList.get(row);
+    }
+
     editorCell = new ContributedLibraryTableCellJPanel(table, value, true);
     editorCell.installButton
         .addActionListener(e -> onInstall(editorValue.getSelected(),
@@ -135,6 +142,9 @@ public Component getTableCellEditorComponent(JTable table, Object value,
         .setVisible(installed == null && uninstalledReleases.size() > 1);
 
     editorCell.setBackground(new Color(218, 227, 227)); // #dae3e3
+
+    cellList.add(row, editorCell);
+
     return editorCell;
   }
 

app/src/cc/arduino/contributions/packages/ui/ContributedPlatformTableCellEditor.java

@@ -33,6 +33,7 @@
 
 import java.awt.Color;
 import java.awt.Component;
+import java.util.ArrayList;
 import java.util.Collections;
 import java.util.LinkedList;
 import java.util.List;
@@ -51,6 +52,8 @@
 @SuppressWarnings("serial")
 public class ContributedPlatformTableCellEditor extends InstallerTableCell {
 
+  private List<Component> cellList = new ArrayList<Component>();
+
   private ContributedPlatformTableCellJPanel cell;
   private ContributedPlatformReleases value;
 
@@ -65,6 +68,10 @@ public Component getTableCellEditorComponent(JTable table, Object _value,
                                                int column) {
     value = (ContributedPlatformReleases) _value;
 
+    if (cellList.size() > row && cellList.get(row) != null) {
+      return cellList.get(row);
+    }
+
     cell = new ContributedPlatformTableCellJPanel();
     cell.installButton.addActionListener(e -> onInstall(value.getSelected(),
                                                         value.getInstalled()));
@@ -74,9 +81,10 @@ public Component getTableCellEditorComponent(JTable table, Object _value,
           .getSelectedItem();
       onInstall(selected, value.getInstalled());
     });
-    cell.versionToInstallChooser.addItemListener(e -> value
-        .select((ContributedPlatform) cell.versionToInstallChooser
-            .getSelectedItem()));
+    cell.versionToInstallChooser.addItemListener(e -> {
+      value.select((ContributedPlatform) cell.versionToInstallChooser
+            .getSelectedItem());
+    });
 
     setEnabled(true);
 
@@ -129,6 +137,9 @@ public Component getTableCellEditorComponent(JTable table, Object _value,
 
     cell.update(table, _value, true, !installedBuiltIn.isEmpty());
     cell.setBackground(new Color(218, 227, 227)); // #dae3e3
+
+    cellList.add(row, cell);
+
     return cell;
   }
 

app/src/cc/arduino/contributions/ui/InstallerJDialog.java

@@ -171,10 +171,15 @@ public void keyReleased(KeyEvent keyEvent) {
 
     contribTable.addMouseMotionListener(new MouseMotionListener() {
 
+        private int previousRowAtPoint = -1;
+
         public void mouseDragged(MouseEvent e) {}
 
         public void mouseMoved(MouseEvent e) {
-            contribTable.editCellAt(contribTable.rowAtPoint(e.getPoint()), 0);
+            if (contribTable.rowAtPoint(e.getPoint()) != previousRowAtPoint) {
+              contribTable.editCellAt(contribTable.rowAtPoint(e.getPoint()), 0);
+              previousRowAtPoint = contribTable.rowAtPoint(e.getPoint());
+            }
         }
     });