Add collapse and expand events to TreeGrid (#8889)

Closes #8760 

2 files changed, 39 insertions, 0 deletions

diff --git a/uitest/src/main/java/com/vaadin/tests/components/treegrid/TreeGridBasicFeatures.java b/uitest/src/main/java/com/vaadin/tests/components/treegrid/TreeGridBasicFeatures.java
index 7998537a6e..3b58e6c75e 100644
--- a/uitest/src/main/java/com/vaadin/tests/components/treegrid/TreeGridBasicFeatures.java
+++ b/uitest/src/main/java/com/vaadin/tests/components/treegrid/TreeGridBasicFeatures.java
@@ -54,6 +54,7 @@ public class TreeGridBasicFeatures extends AbstractComponentTest<TreeGrid> {
 
         createDataProviderSelect();
         createHierarchyColumnSelect();
+        createListenerMenu();
     }
 
     private void initializeDataProviders() {
@@ -102,6 +103,16 @@ public class TreeGridBasicFeatures extends AbstractComponentTest<TreeGrid> {
                 (treeGrid, value, data) -> treeGrid.setHierarchyColumn(value));
     }
 
+    @SuppressWarnings("unchecked")
+    private void createListenerMenu() {
+        createListenerAction("Collapse listener", "State",
+                treeGrid -> treeGrid.addCollapseListener(event -> log(
+                        "Item collapsed: " + event.getCollapsedItem())));
+        createListenerAction("Expand listener", "State",
+                treeGrid -> treeGrid.addExpandListener(event -> log(
+                        "Item expanded: " + event.getExpandedItem())));
+    }
+
     static class HierarchicalTestBean {
 
         private final String id;
diff --git a/uitest/src/test/java/com/vaadin/tests/components/treegrid/TreeGridBasicFeaturesTest.java b/uitest/src/test/java/com/vaadin/tests/components/treegrid/TreeGridBasicFeaturesTest.java
index b01a6273e2..215bef95d2 100644
--- a/uitest/src/test/java/com/vaadin/tests/components/treegrid/TreeGridBasicFeaturesTest.java
+++ b/uitest/src/test/java/com/vaadin/tests/components/treegrid/TreeGridBasicFeaturesTest.java
@@ -119,6 +119,34 @@ public class TreeGridBasicFeaturesTest extends MultiBrowserTest {
                 .isElementPresent(By.className("v-tree-grid-expander")));
     }
 
+    @Test
+    public void expand_and_collapse_listeners() {
+        selectMenuPath("Component", "State", "Expand listener");
+        selectMenuPath("Component", "State", "Collapse listener");
+
+        Assert.assertFalse(logContainsText("Item expanded: 0 | 0"));
+        Assert.assertFalse(logContainsText("Item collapsed: 0 | 0"));
+
+        grid.collapseWithClick(0);
+
+        Assert.assertTrue(logContainsText("Item expanded: 0 | 0"));
+        Assert.assertFalse(logContainsText("Item collapsed: 0 | 0"));
+
+        grid.collapseWithClick(0);
+
+        Assert.assertTrue(logContainsText("Item expanded: 0 | 0"));
+        Assert.assertTrue(logContainsText("Item collapsed: 0 | 0"));
+
+        selectMenuPath("Component", "State", "Expand listener");
+        selectMenuPath("Component", "State", "Collapse listener");
+
+        grid.collapseWithClick(1);
+        grid.collapseWithClick(1);
+
+        Assert.assertFalse(logContainsText("Item expanded: 0 | 1"));
+        Assert.assertFalse(logContainsText("Item collapsed: 0 | 1"));
+    }
+
     private void assertCellTexts(int startRowIndex, int cellIndex,
             String[] cellTexts) {
         int index = startRowIndex;