Make initially disabled grid work when enabled (#20240)

Adds API to allow grid to ask its data source if it is waiting for data.
The previous tracking inside grid was not always correct as it relied
on dataAvailable being called.

Change-Id: I0bdb448d9b720155940b0834e118f0eca27a3bfc

client/src/main/java/com/vaadin/client/connectors/RpcDataSourceConnector.java

@@ -240,6 +240,11 @@ public class RpcDataSourceConnector extends AbstractExtensionConnector {
                 droppedRowKeys.set(droppedRowKeys.length(), getRowKey(row));
             }
         }
+
+        @Override
+        protected boolean canFetchData() {
+            return isEnabled();
+        }
     }
 
     private final RpcDataSource dataSource = new RpcDataSource();

client/src/main/java/com/vaadin/client/data/AbstractRemoteDataSource.java

@@ -308,6 +308,7 @@ public abstract class AbstractRemoteDataSource<T> implements DataSource<T> {
      * @return <code>true</code> if waiting for data; otherwise
      *         <code>false</code>
      */
+    @Override
     public boolean isWaitingForData() {
         return currentRequestCallback != null;
     }
@@ -366,7 +367,7 @@ public abstract class AbstractRemoteDataSource<T> implements DataSource<T> {
     }
 
     private void handleMissingRows(Range range) {
-        if (range.isEmpty()) {
+        if (range.isEmpty() || !canFetchData()) {
             return;
         }
         currentRequestCallback = new RequestRowsCallback<T>(this, range);
@@ -776,4 +777,17 @@ public abstract class AbstractRemoteDataSource<T> implements DataSource<T> {
     protected boolean isPinned(T row) {
         return pinnedRows.containsKey(getRowKey(row));
     }
+
+    /**
+     * Checks if it is possible to currently fetch data from the remote data
+     * source.
+     * 
+     * @return <code>true</code> if it is ok to try to fetch data,
+     *         <code>false</code> if it is known that fetching data will fail
+     *         and should not be tried right now.
+     * @since 7.7.2
+     */
+    protected boolean canFetchData() {
+        return true;
+    }
 }

client/src/main/java/com/vaadin/client/data/DataSource.java

@@ -194,4 +194,14 @@ public interface DataSource<T> {
      *        means that the row is not currently in this data source's cache.
      */
     public RowHandle<T> getHandle(T row);
+
+    /**
+     * Checks whether this data source is currently waiting for more rows to
+     * become available.
+     *
+     * @return <code>true</code> if waiting for data; otherwise
+     *         <code>false</code>
+     * @since 7.7.2
+     */
+    public boolean isWaitingForData();
 }

client/src/main/java/com/vaadin/client/widget/grid/datasources/ListDataSource.java

@@ -475,4 +475,9 @@ public class ListDataSource<T> implements DataSource<T> {
             }
         };
     }
+
+    @Override
+    public boolean isWaitingForData() {
+        return false;
+    }
 }

client/src/main/java/com/vaadin/client/widgets/Grid.java

@@ -3188,7 +3188,7 @@ public class Grid<T> extends ResizeComposite implements HasSelectionHandlers<T>,
                         Scheduler.get().scheduleDeferred(this);
                     }
                 } else if (currentDataAvailable.isEmpty()
-                        && dataIsBeingFetched) {
+                        && dataSource.isWaitingForData()) {
                     // No data available yet but something is incoming soon
                     Scheduler.get().scheduleDeferred(this);
                 } else {
@@ -3224,8 +3224,8 @@ public class Grid<T> extends ResizeComposite implements HasSelectionHandlers<T>,
         private void calculate() {
             isScheduled = false;
             rescheduleCount = 0;
-            assert !(currentDataAvailable.isEmpty()
-                    && dataIsBeingFetched) : "Trying to calculate column widths without data while data is still being fetched.";
+            assert !(currentDataAvailable.isEmpty() && dataSource
+                    .isWaitingForData()) : "Trying to calculate column widths without data while data is still being fetched.";
 
             if (columnsAreGuaranteedToBeWiderThanGrid()) {
                 applyColumnWidths();
@@ -4086,8 +4086,6 @@ public class Grid<T> extends ResizeComposite implements HasSelectionHandlers<T>,
 
     private final Editor<T> editor = GWT.create(Editor.class);
 
-    private boolean dataIsBeingFetched = false;
-
     /**
      * The cell a click event originated from
      * <p>
@@ -5955,7 +5953,6 @@ public class Grid<T> extends ResizeComposite implements HasSelectionHandlers<T>,
                     public void onRowVisibilityChange(
                             RowVisibilityChangeEvent event) {
                         if (dataSource != null && dataSource.size() != 0) {
-                            dataIsBeingFetched = true;
                             dataSource.ensureAvailability(
                                     event.getFirstVisibleRow(),
                                     event.getVisibleRowCount());
@@ -5995,12 +5992,6 @@ public class Grid<T> extends ResizeComposite implements HasSelectionHandlers<T>,
             }
         });
 
-        addDataAvailableHandler(new DataAvailableHandler() {
-            @Override
-            public void onDataAvailable(DataAvailableEvent event) {
-                dataIsBeingFetched = false;
-            }
-        });
     }
 
     @Override
@@ -6775,7 +6766,6 @@ public class Grid<T> extends ResizeComposite implements HasSelectionHandlers<T>,
                 }
 
                 if (newSize > 0) {
-                    dataIsBeingFetched = true;
                     Range visibleRowRange = escalator.getVisibleRowRange();
                     dataSource.ensureAvailability(visibleRowRange.getStart(),
                             visibleRowRange.length());
@@ -7915,7 +7905,7 @@ public class Grid<T> extends ResizeComposite implements HasSelectionHandlers<T>,
         Scheduler.get().scheduleFinally(new ScheduledCommand() {
             @Override
             public void execute() {
-                if (!dataIsBeingFetched) {
+                if (!dataSource.isWaitingForData()) {
                     handler.onDataAvailable(
                             new DataAvailableEvent(currentDataAvailable));
                 }
@@ -8236,7 +8226,7 @@ public class Grid<T> extends ResizeComposite implements HasSelectionHandlers<T>,
 
     @Override
     public boolean isWorkPending() {
-        return escalator.isWorkPending() || dataIsBeingFetched
+        return escalator.isWorkPending() || dataSource.isWaitingForData()
                 || autoColumnWidthsRecalculator.isScheduled()
                 || editor.isWorkPending();
     }

uitest/src/main/java/com/vaadin/tests/components/grid/InitiallyDisabledGrid.java

@@ -5,43 +5,16 @@ import java.util.Collection;
 
 import com.vaadin.data.util.BeanItemContainer;
 import com.vaadin.server.VaadinRequest;
+import com.vaadin.tests.data.bean.Person;
 import com.vaadin.ui.Button;
+import com.vaadin.ui.Button.ClickEvent;
+import com.vaadin.ui.Button.ClickListener;
 import com.vaadin.ui.Grid;
 import com.vaadin.ui.UI;
 import com.vaadin.ui.VerticalLayout;
 
 public class InitiallyDisabledGrid extends UI {
 
-    public static class NotAPersonJustStringAndInt {
-        private String name;
-
-        public NotAPersonJustStringAndInt() {
-        }
-
-        public NotAPersonJustStringAndInt(String string, int i) {
-            name = string;
-            age = i;
-        }
-
-        public int getAge() {
-            return age;
-        }
-
-        public void setAge(int age) {
-            this.age = age;
-        }
-
-        private int age;
-
-        public void setName(String name) {
-            this.name = name;
-        }
-
-        public String getName() {
-            return name;
-        }
-    }
-
     @Override
     protected void init(VaadinRequest request) {
         VerticalLayout layout = new VerticalLayout();
@@ -49,13 +22,18 @@ public class InitiallyDisabledGrid extends UI {
         layout.setSizeFull();
         layout.setWidth("600px");
         layout.setHeight("600px");
-        final Grid g = createGrid();
-        Button button = new Button("Sample button");
+        final Grid grid = createGrid();
+        Button button = new Button("Enable/Disable", new ClickListener() {
+            @Override
+            public void buttonClick(ClickEvent event) {
+                grid.setEnabled(!grid.isEnabled());
+            }
+        });
 
         layout.addComponent(button);
         VerticalLayout l = new VerticalLayout();
         l.setSizeFull();
-        l.addComponent(g);
+        l.addComponent(grid);
 
         layout.addComponent(l);
         layout.setExpandRatio(l, 1.0f);
@@ -63,18 +41,22 @@ public class InitiallyDisabledGrid extends UI {
 
     private Grid createGrid() {
         // Have some data
-        Collection<NotAPersonJustStringAndInt> people = new ArrayList<NotAPersonJustStringAndInt>();
+        Collection<Person> people = new ArrayList<Person>();
         for (int i = 0; i < 100; i++) {
-            people.add(new NotAPersonJustStringAndInt("A " + i, i));
+            Person person = new Person();
+            person.setFirstName("First " + i);
+            person.setLastName("Last " + i);
+            people.add(person);
+
         }
         // Have a container of some type to contain the data
-        BeanItemContainer<NotAPersonJustStringAndInt> container = new BeanItemContainer<NotAPersonJustStringAndInt>(
-                NotAPersonJustStringAndInt.class, people);
+        BeanItemContainer<Person> container = new BeanItemContainer<Person>(
+                Person.class, people);
 
         // Create a grid bound to the container
         Grid grid = new Grid(container);
         grid.setSizeFull();
-        grid.setColumnOrder("name", "age");
+        grid.setColumns("firstName", "lastName");
 
         grid.setEnabled(false);
 

uitest/src/main/java/com/vaadin/tests/widgetset/client/grid/GridCellFocusOnResetSizeWidget.java

@@ -78,6 +78,11 @@ public class GridCellFocusOnResetSizeWidget
             }
             handler.resetDataAndSize(size);
         }
+
+        @Override
+        public boolean isWaitingForData() {
+            return false;
+        }
     }
 
     private class Col extends Grid.Column<String, String[]> {

uitest/src/main/java/com/vaadin/tests/widgetset/client/grid/GridClientColumnRendererConnector.java

@@ -68,6 +68,7 @@ public class GridClientColumnRendererConnector
         private int numberOfRows;
         private DataChangeHandler dataChangeHandler;
         private int latency;
+        private Timer timer;
 
         public DelayedDataSource(DataSource<String> ds, int latency) {
             this.ds = ds;
@@ -77,7 +78,7 @@ public class GridClientColumnRendererConnector
         @Override
         public void ensureAvailability(final int firstRowIndex,
                 final int numberOfRows) {
-            new Timer() {
+            timer = new Timer() {
 
                 @Override
                 public void run() {
@@ -86,8 +87,10 @@ public class GridClientColumnRendererConnector
                     dataChangeHandler.dataUpdated(firstRowIndex, numberOfRows);
                     dataChangeHandler.dataAvailable(firstRowIndex,
                             numberOfRows);
+                    timer = null;
                 }
-            }.schedule(latency);
+            };
+            timer.schedule(latency);
         }
 
         @Override
@@ -114,6 +117,11 @@ public class GridClientColumnRendererConnector
             // TODO Auto-generated method stub (henrik paul: 17.6.)
             return null;
         }
+
+        @Override
+        public boolean isWaitingForData() {
+            return timer != null;
+        }
     }
 
     @Override

uitest/src/test/java/com/vaadin/tests/components/grid/InitiallyDisabledGridTest.java

@@ -3,6 +3,7 @@ package com.vaadin.tests.components.grid;
 import org.junit.Assert;
 import org.junit.Test;
 
+import com.vaadin.testbench.elements.ButtonElement;
 import com.vaadin.testbench.elements.GridElement;
 import com.vaadin.testbench.elements.GridElement.GridCellElement;
 import com.vaadin.tests.tb3.SingleBrowserTest;
@@ -19,4 +20,16 @@ public class InitiallyDisabledGridTest extends SingleBrowserTest {
         Assert.assertTrue(col0.getSize().getWidth() > 250);
         Assert.assertTrue(col1.getSize().getWidth() > 250);
     }
+
+    @Test
+    public void worksWhenEnabled() {
+        openTestURL();
+        $(ButtonElement.class).first().click();
+
+        GridElement grid = $(GridElement.class).first();
+        grid.scrollToRow(80);
+        GridCellElement col0 = grid.getCell(80, 0);
+        Assert.assertEquals("First 80", col0.getText());
+    }
+
 }