Fix partly missing drag image regression on Safari

Doesn't fix #9261, drag image missing on Safari when dragging grid row because
that has position: absolute and offset.

2 files changed, 69 insertions, 1 deletions

diff --git a/uitest/src/main/java/com/vaadin/tests/components/grid/GridDragAndDrop.java b/uitest/src/main/java/com/vaadin/tests/components/grid/GridDragAndDrop.java
index 149dec92e3..529d8cf562 100644
--- a/uitest/src/main/java/com/vaadin/tests/components/grid/GridDragAndDrop.java
+++ b/uitest/src/main/java/com/vaadin/tests/components/grid/GridDragAndDrop.java
@@ -122,7 +122,8 @@ public class GridDragAndDrop extends AbstractTestUIWithLog {
 
         // Add drag end listener
         dragSource.addGridDragEndListener(event -> {
-            if (event.getDropEffect() == DropEffect.MOVE) {
+            if (event.getDropEffect() == DropEffect.MOVE
+                    && draggedItems != null) {
                 // If drop is successful, remove dragged item from source Grid
                 ((ListDataProvider<Person>) grid.getDataProvider()).getItems()
                         .removeAll(draggedItems);
diff --git a/uitest/src/main/java/com/vaadin/tests/dnd/DragImage.java b/uitest/src/main/java/com/vaadin/tests/dnd/DragImage.java
new file mode 100644
index 0000000000..b4ef7ea035
--- /dev/null
+++ b/uitest/src/main/java/com/vaadin/tests/dnd/DragImage.java
@@ -0,0 +1,67 @@
+package com.vaadin.tests.dnd;
+
+import java.util.stream.Stream;
+
+import com.vaadin.annotations.Theme;
+import com.vaadin.annotations.Widgetset;
+import com.vaadin.event.dnd.DragSourceExtension;
+import com.vaadin.server.Page;
+import com.vaadin.server.Page.Styles;
+import com.vaadin.server.ThemeResource;
+import com.vaadin.server.VaadinRequest;
+import com.vaadin.tests.components.AbstractTestUIWithLog;
+import com.vaadin.tests.components.uitest.TestSampler;
+import com.vaadin.ui.HorizontalLayout;
+import com.vaadin.ui.Label;
+import com.vaadin.ui.VerticalLayout;
+
+@Theme("valo")
+@Widgetset("com.vaadin.DefaultWidgetSet")
+public class DragImage extends AbstractTestUIWithLog {
+
+    private final String[] positions = { "default", "relative", "absolute",
+            "static", "fixed", "sticky", "inherit", "initial", "unset" };
+
+    @Override
+    protected void setup(VaadinRequest request) {
+        HorizontalLayout layout1 = new HorizontalLayout();
+        layout1.setCaption("No custom drag image");
+        Styles styles = Page.getCurrent().getStyles();
+
+        Stream.of(positions).forEach(position -> {
+            Label label = new Label(position);
+            label.addStyleName(position);
+            new DragSourceExtension<>(label);
+
+            layout1.addComponents(label, new Label("spacer"));
+
+            styles.add(new StringBuilder(".").append(position)
+                    .append(" { position: ").append(position).append(";}")
+                    .toString());
+        });
+
+        HorizontalLayout layout2 = new HorizontalLayout();
+        layout2.setCaption("Custom drag image");
+        Stream.of(positions).forEach(position -> {
+            Label label = new Label(position);
+            label.addStyleName(position);
+            new DragSourceExtension<>(label)
+                    .setDragImage(new ThemeResource(TestSampler.ICON_URL));
+            layout2.addComponents(label, new Label("spacer"));
+
+            styles.add(new StringBuilder(".").append(position)
+                    .append(" { position: ").append(position).append(";}")
+                    .toString());
+        });
+
+        // #9261 grid row like element that safari can't show the drag image for
+        String css = ".absolute-pos { position: absolute; top:0; }";
+        Label gridRowLikeLabel = new Label(css);
+        gridRowLikeLabel.addStyleName("absolute-pos");
+        new DragSourceExtension(gridRowLikeLabel);
+        styles.add(css);
+
+        addComponent(new VerticalLayout(layout1, layout2, gridRowLikeLabel));
+    }
+
+}