Fix mouse wheel scrolling of ComboBox in IE11 (#16918)

IE11 is broken so that the simple implementation always moves up on any
mouse wheel event. Therefore, this change borrows the approach taken by
Escalator for low-level handling of mouse wheel events in a way compatible
with all supported browsers.

Change-Id: I98c89d3ccfeea38d6a454ef708f0eb7d1d3f480c

1 files changed, 59 insertions, 0 deletions

diff --git a/uitest/src/com/vaadin/tests/components/combobox/ComboBoxMousewheel.java b/uitest/src/com/vaadin/tests/components/combobox/ComboBoxMousewheel.java
new file mode 100644
index 0000000000..802e7480f5
--- /dev/null
+++ b/uitest/src/com/vaadin/tests/components/combobox/ComboBoxMousewheel.java
@@ -0,0 +1,59 @@
+/*
+ * Copyright 2000-2014 Vaadin Ltd.
+ * 
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may not
+ * use this file except in compliance with the License. You may obtain a copy of
+ * the License at
+ * 
+ * http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations under
+ * the License.
+ */
+package com.vaadin.tests.components.combobox;
+
+import com.vaadin.server.VaadinRequest;
+import com.vaadin.tests.components.AbstractTestUI;
+import com.vaadin.ui.ComboBox;
+
+/**
+ * Tests mousewheel handling in ComboBox.
+ * 
+ * @author Vaadin Ltd
+ */
+public class ComboBoxMousewheel extends AbstractTestUI {
+
+    @Override
+    protected void setup(VaadinRequest request) {
+        addComponent(createComboBox("Paged"));
+
+        ComboBox cb = createComboBox("Unpaged");
+        cb.setPageLength(0);
+        addComponent(cb);
+    }
+
+    private ComboBox createComboBox(String caption) {
+        ComboBox cb = new ComboBox(caption);
+        cb.setId(caption);
+        cb.setImmediate(true);
+        for (int i = 1; i < 100; i++) {
+            cb.addItem("Item " + i);
+        }
+        return cb;
+    }
+
+    @Override
+    protected String getTestDescription() {
+        return "ComboBox scrolling should be possible to both directions on Paged + IE as well.<br>"
+                + "IE should not move paging up when scrolled down.";
+    }
+
+    @Override
+    protected Integer getTicketNumber() {
+        return 16918;
+    }
+
+}