Prevent text selection while DnD resizing columns (#16838)

This patch uses a JavaScript workaround to prevent text selection in IE8
and IE9 and Safari.

The selection is prevented everywhere in the DOM while a column is
resizing.

Change-Id: I1e7b9cdc675c83a9666493d8545337d601e40077

2 files changed, 32 insertions, 0 deletions

diff --git a/client/src/com/vaadin/client/WidgetUtil.java b/client/src/com/vaadin/client/WidgetUtil.java
index e9ec163612..b0e0030769 100644
--- a/client/src/com/vaadin/client/WidgetUtil.java
+++ b/client/src/com/vaadin/client/WidgetUtil.java
@@ -1307,6 +1307,29 @@ public class WidgetUtil {
     }-*/;
 
     /**
+     * JavaScript hack to prevent text selection in various browsers.
+     * 
+     * @since
+     * @param e
+     *            element for enabling or disabling text selection
+     * @param enable
+     *            <code>true</code> if selection is enabled; </code>false</code>
+     *            if not
+     */
+    public native static void setTextSelectionEnabled(Element e, boolean enable)
+    /*-{
+        if (!enable) {
+            e.ondrag = function () { return false; };
+            e.onselectstart = function () { return false; };
+            e.style.webkitUserSelect = "none";
+        } else {
+            e.ondrag = null;
+            e.onselectstart = null;
+            e.style.webkitUserSelect = "text";
+        }
+    }-*/;
+
+    /**
      * The allowed value inaccuracy when comparing two double-typed pixel
      * values.
      * <p>
diff --git a/client/src/com/vaadin/client/widgets/Grid.java b/client/src/com/vaadin/client/widgets/Grid.java
index a5a93c19ef..33672517fe 100644
--- a/client/src/com/vaadin/client/widgets/Grid.java
+++ b/client/src/com/vaadin/client/widgets/Grid.java
@@ -36,6 +36,7 @@ import com.google.gwt.core.client.Scheduler.ScheduledCommand;
 import com.google.gwt.core.shared.GWT;
 import com.google.gwt.dom.client.BrowserEvents;
 import com.google.gwt.dom.client.DivElement;
+import com.google.gwt.dom.client.Document;
 import com.google.gwt.dom.client.Element;
 import com.google.gwt.dom.client.EventTarget;
 import com.google.gwt.dom.client.NativeEvent;
@@ -5580,16 +5581,24 @@ public class Grid<T> extends ResizeComposite implements
                                                     c));
                                         }
                                     }
+                                    WidgetUtil.setTextSelectionEnabled(Document
+                                            .get().getBody(), false);
                                 }
 
                                 @Override
                                 public void onComplete() {
                                     fireEvent(new ColumnResizeEvent<T>(col));
+
+                                    WidgetUtil.setTextSelectionEnabled(Document
+                                            .get().getBody(), true);
                                 }
 
                                 @Override
                                 public void onCancel() {
                                     col.setWidth(initialWidth);
+
+                                    WidgetUtil.setTextSelectionEnabled(Document
+                                            .get().getBody(), true);
                                 }
                             });
                     dragger.addTo(td);