#4143 Fix horizontal scroll

Author: stroomdev66

Diff for: stroom-core-client-widget/src/main/java/com/google/gwt/user/client/ui/FocusUtil.java

@@ -26,8 +26,7 @@ public static void focusRow(final Element elem) {
             tr = tr.getParentElement();
         }
         if (tr != null) {
-//            tr.focus();
-            ElementUtil.scrollIntoViewNearest(tr);
+            ElementUtil.scrollIntoViewVertical(tr);
         }
 
         ElementUtil.focus(elem, false, true);

Diff for: stroom-core-client-widget/src/main/java/stroom/data/grid/client/DataGridSelectionEventManager.java

@@ -117,16 +117,18 @@ protected void onMouseDown(final CellPreviewEvent<T> event) {
             }
 
             if (!consumed) {
-                // We set focus here so that we can use the keyboard to navigate once we have focus.
-                dataGrid.setFocus(true);
-
-                GwtNullSafe.consume(event.getValue(), value -> {
+                int index = -1;
+                if (event.getValue() != null) {
                     final List<T> rows = dataGrid.getVisibleItems();
-                    final int index = rows.indexOf(value);
-                    if (index != -1) {
-                        dataGrid.setKeyboardSelectedRow(index);
-                    }
-                });
+                    index = rows.indexOf(event.getValue());
+                }
+                if (index == -1) {
+                    index = dataGrid.getKeyboardSelectedRow();
+                }
+                if (index != -1) {
+                    // We set focus here so that we can use the keyboard to navigate once we have focus.
+                    dataGrid.setKeyboardSelectedRow(index, true);
+                }
 
                 GwtNullSafe.consume(event.getValue(), row -> {
                     final boolean doubleClick = doubleClickTest.test(row);

Diff for: stroom-core-client-widget/src/main/java/stroom/widget/util/client/ElementUtil.java

@@ -170,6 +170,60 @@ public static native void scrollIntoView(Element el, boolean alignToTop) /*-{
     }-*/;
 
     public static native void scrollIntoViewNearest(Element el) /*-{
-        el.scrollIntoView({behaviour: "auto", block: "nearest", inline: "nearest"});
+        el.scrollIntoView({behaviour: "auto", block: "start", inline: "nearest"});
+    }-*/;
+
+    public static native void scrollIntoViewVertical(Element elem) /*-{
+        var top = elem.offsetTop;
+        var height = elem.offsetHeight;
+
+        if (elem.parentNode != elem.offsetParent) {
+            top -= elem.parentNode.offsetTop;
+        }
+
+        var cur = elem.parentNode;
+        while (cur && (cur.nodeType == 1)) {
+            if (top < cur.scrollTop) {
+                cur.scrollTop = top;
+            }
+            if (top + height > cur.scrollTop + cur.clientHeight) {
+                cur.scrollTop = (top + height) - cur.clientHeight;
+            }
+
+            var offsetTop = cur.offsetTop;
+            if (cur.parentNode != cur.offsetParent) {
+                offsetTop -= cur.parentNode.offsetTop;
+            }
+
+            top += offsetTop - cur.scrollTop;
+            cur = cur.parentNode;
+        }
+    }-*/;
+
+    public static native void scrollIntoViewHorizontal(Element elem) /*-{
+        var left = elem.offsetLeft;
+        var width = elem.offsetWidth;
+
+        if (elem.parentNode != elem.offsetParent) {
+            left -= elem.parentNode.offsetLeft;
+        }
+
+        var cur = elem.parentNode;
+        while (cur && (cur.nodeType == 1)) {
+            if (left < cur.scrollLeft) {
+                cur.scrollLeft = left;
+            }
+            if (left + width > cur.scrollLeft + cur.clientWidth) {
+                cur.scrollLeft = (left + width) - cur.clientWidth;
+            }
+
+            var offsetLeft = cur.offsetLeft;
+            if (cur.parentNode != cur.offsetParent) {
+                offsetLeft -= cur.parentNode.offsetLeft;
+            }
+
+            left += offsetLeft - cur.scrollLeft;
+            cur = cur.parentNode;
+        }
     }-*/;
 }