More specific workaround for no rows in TreeTable with pagelenght = 0 (#9203)

svn changeset:25915/svn branch:6.8

Conflicts:
	client/src/com/vaadin/client/ui/VScrollTable.java

Change-Id: I3f5b9dc988f5911023f77f184f5bd6770bbd9f1b

1 files changed, 27 insertions, 6 deletions

diff --git a/client/src/com/vaadin/client/ui/VScrollTable.java b/client/src/com/vaadin/client/ui/VScrollTable.java
index 4d61fba429..b03fa945cd 100644
--- a/client/src/com/vaadin/client/ui/VScrollTable.java
+++ b/client/src/com/vaadin/client/ui/VScrollTable.java
@@ -1113,10 +1113,10 @@ public class VScrollTable extends FlowPanel implements HasWidgets,
         if (firstvisible != lastRequestedFirstvisible && scrollBody != null) {
             // received 'surprising' firstvisible from server: scroll there
             firstRowInViewPort = firstvisible;
-          
+
             /*
-             * Schedule the scrolling to be executed last so no updates to the rows
-             * affect scrolling measurements.
+             * Schedule the scrolling to be executed last so no updates to the
+             * rows affect scrolling measurements.
              */
             Scheduler.get().scheduleFinally(lazyScroller);
         }
@@ -2104,6 +2104,15 @@ public class VScrollTable extends FlowPanel implements HasWidgets,
              * might have been (incorrectly) calculated earlier
              */
 
+            /*
+             * TreeTable updates stuff in a funky order, so we must set the
+             * height as zero here before doing the real update to make it
+             * realize that there is no content,
+             */
+            if (pageLength == totalRows && pageLength == 0) {
+                scrollBody.setHeight("0px");
+            }
+
             int bodyHeight;
             if (pageLength == totalRows) {
                 /*
@@ -3056,7 +3065,7 @@ public class VScrollTable extends FlowPanel implements HasWidgets,
                                 .hasNext(); columnIndex++) {
                             if (it.next() == this) {
                                 break;
-                            }                          
+                            }
                         }
                     }
                     final int cw = scrollBody.getColWidth(columnIndex);
@@ -4796,8 +4805,20 @@ public class VScrollTable extends FlowPanel implements HasWidgets,
                 prepx = 0;
             }
             preSpacer.getStyle().setPropertyPx("height", prepx);
-            int postpx = measureRowHeightOffset(totalRows - 1)
-                    - measureRowHeightOffset(lastRendered);
+            int postpx;
+            if (pageLength == 0 && totalRows == pageLength) {
+                /*
+                 * TreeTable depends on having lastRendered out of sync in some
+                 * situations, which makes this method miss the special
+                 * situation in which one row worth of post spacer to be added
+                 * if there are no rows in the table. #9203
+                 */
+                postpx = measureRowHeightOffset(1);
+            } else {
+                postpx = measureRowHeightOffset(totalRows - 1)
+                        - measureRowHeightOffset(lastRendered);
+            }
+
             if (postpx < 0) {
                 postpx = 0;
             }