Increase Tooltip z-index to be larger than the default overlay z-index. (#14854)

Change-Id: Ib6a2f77aadc9cb1afe8a8e43be9916de3d2eaf44

client/src/com/vaadin/client/VTooltip.java

@@ -89,6 +89,9 @@ public class VTooltip extends VOverlay {
                 LiveValue.ASSERTIVE);
         Roles.getTooltipRole().setAriaRelevantProperty(getElement(),
                 RelevantValue.ADDITIONS);
+
+        // Tooltip needs to be on top of other VOverlay elements.
+        setZIndex(VOverlay.Z_INDEX + 1);
     }
 
     /**

uitest/src/com/vaadin/tests/tooltip/MenuBarTooltip.java

@@ -0,0 +1,34 @@
+package com.vaadin.tests.tooltip;
+
+import com.vaadin.server.VaadinRequest;
+import com.vaadin.tests.components.AbstractTestUI;
+import com.vaadin.ui.MenuBar;
+
+public class MenuBarTooltip extends AbstractTestUI {
+
+    @Override
+    protected void setup(VaadinRequest request) {
+        MenuBar menubar = new MenuBar();
+
+        MenuBar.MenuItem menuitem = menubar.addItem("Menu item", null, null);
+        menuitem.setDescription("Menu item description");
+
+        MenuBar.MenuItem submenuitem1 = menuitem.addItem("Submenu item 1", null, null);
+        submenuitem1.setDescription("Submenu item 1 description");
+
+        MenuBar.MenuItem submenuitem2 = menuitem.addItem("Submenu item 2", null, null);
+        submenuitem2.setDescription("Submenu item 2 description");
+
+        addComponent(menubar);
+    }
+
+    @Override
+    protected Integer getTicketNumber() {
+        return 14854;
+    }
+
+    @Override
+    protected String getTestDescription() {
+        return "MenuItem tooltip should have a larger z-index than MenuBar/MenuItem.";
+    }
+}

uitest/src/com/vaadin/tests/tooltip/MenuBarTooltipTest.java

@@ -0,0 +1,46 @@
+package com.vaadin.tests.tooltip;
+
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.Matchers.greaterThan;
+
+import org.junit.Test;
+import org.openqa.selenium.By;
+
+import com.vaadin.testbench.elements.MenuBarElement;
+import com.vaadin.tests.tb3.MultiBrowserTest;
+import com.vaadin.ui.themes.ChameleonTheme;
+import com.vaadin.ui.themes.Reindeer;
+import com.vaadin.ui.themes.Runo;
+import com.vaadin.ui.themes.ValoTheme;
+
+public class MenuBarTooltipTest extends MultiBrowserTest {
+
+    @Test
+    public void toolTipShouldBeOnTopOfMenuItem() {
+        String[] themes = new String[] {
+                ValoTheme.THEME_NAME,
+                Reindeer.THEME_NAME,
+                Runo.THEME_NAME,
+                ChameleonTheme.THEME_NAME
+        };
+
+        for(String theme : themes) {
+           assertZIndices(theme);
+        }
+    }
+
+    public void assertZIndices(String theme) {
+        openTestURL("theme=" + theme);
+
+        $(MenuBarElement.class).first().clickItem("Menu item");
+
+        assertThat(String.format("Invalid z-index for theme %s.", theme),
+                getZIndex("v-tooltip"), greaterThan(getZIndex("v-menubar-popup")));
+    }
+
+    private int getZIndex(String className) {
+        return Integer.parseInt(
+                findElement(By.className(className)).getCssValue("z-index"));
+    }
+
+}