8279140: ComboBox can lose selected value on item change via setAll

Reviewed-by: angorya

Author: karthikpandelu

modules/javafx.controls/src/main/java/javafx/scene/control/ComboBox.java

@@ -618,14 +618,11 @@ public ComboBoxSelectionModel(final ComboBox<T> cb) {
                     T selectedItem = getSelectedItem();
                     for (int i = 0; i < comboBox.getItems().size(); i++) {
                         if (selectedItem.equals(comboBox.getItems().get(i))) {
-                            comboBox.setValue(null);
-                            setSelectedItem(null);
-                            setSelectedIndex(i);
+                            clearAndSelect(i);
                             break;
                         }
                     }
                 }
-
                 comboBox.previousItemCount = getItemCount();
             }
         };

modules/javafx.controls/src/test/java/test/javafx/scene/control/ComboBoxTest.java

@@ -2318,4 +2318,67 @@ public void test_rt_40012_selectedItemNotificationOnDisjointRemovesAbove() {
 
         assertEquals("ComboBox skinProperty changed more than once, which is not expected.", 1, skinChangedCount);
     }
+
+    //JDK-8279140
+    @Test
+    public void testSelectionOnItemChangeUsingSetAllThroughPropertyBinding() {
+        ObservableList<String> comboBoxItemsList = FXCollections.observableArrayList();
+        ObjectProperty<String> selectedValue = new SimpleObjectProperty<>();
+
+        List<String> strings1 = List.of("A", "B", "C");
+        List<String> strings2 = List.of("D", "E", "F");
+
+        comboBox = new ComboBox<>();
+        comboBox.setItems(comboBoxItemsList);
+
+        selectedValue.addListener((obs, oldValue, newValue) -> {
+            if ("D".equals(newValue) || "A".equals(newValue)) {
+                List<String> newContent = "A".equals(newValue) ? strings1 : strings2;
+                comboBoxItemsList.setAll(newContent);
+            }
+        });
+
+        comboBox.valueProperty().bindBidirectional(selectedValue);
+
+        selectedValue.set("A");
+        assertEquals("A", comboBox.getSelectionModel().getSelectedItem());
+        assertEquals("A", selectedValue.get());
+
+        selectedValue.set("D");
+        assertEquals("D", comboBox.getSelectionModel().getSelectedItem());
+        assertEquals("D", selectedValue.get());
+    }
+
+    //JDK-8279139
+    @Test
+    public void testSelectionOnItemChangeUsingSetAllOnButtonPress() {
+        ObservableList<String> comboBoxItemsList = FXCollections.observableArrayList();
+
+        List<String> strings1 = List.of("A", "B", "C");
+        List<String> strings2 = List.of("D", "B", "F");
+
+        comboBox = new ComboBox<>();
+        comboBox.setItems(comboBoxItemsList);
+        comboBox.setValue("B");
+
+        comboBoxItemsList.setAll(strings2);
+        assertEquals("B", comboBox.getSelectionModel().getSelectedItem());
+        comboBoxItemsList.setAll(strings1);
+        assertEquals("B", comboBox.getSelectionModel().getSelectedItem());
+
+        Button button = new Button("Change content");
+        button.setOnAction(e -> {
+            if (comboBoxItemsList.equals(strings1)) {
+                comboBoxItemsList.setAll(strings2);
+            } else {
+                comboBoxItemsList.setAll(strings1);
+            }
+        });
+
+        MouseEventFirer mouse = new MouseEventFirer(button);
+        mouse.fireMousePressAndRelease();
+        assertEquals("B", comboBox.getSelectionModel().getSelectedItem());
+        mouse.fireMousePressAndRelease();
+        assertEquals("B", comboBox.getSelectionModel().getSelectedItem());
+    }
 }