All updates to Escalator size should get reported to LayoutManager. (#12050)

Delayed size changes caused by added or removed scrollbars should be
taken into account.

2 files changed, 204 insertions, 0 deletions

diff --git a/uitest/src/main/java/com/vaadin/tests/components/grid/GridSizeChange.java b/uitest/src/main/java/com/vaadin/tests/components/grid/GridSizeChange.java
new file mode 100644
index 0000000000..a446e47d90
--- /dev/null
+++ b/uitest/src/main/java/com/vaadin/tests/components/grid/GridSizeChange.java
@@ -0,0 +1,109 @@
+package com.vaadin.tests.components.grid;
+
+import java.util.ArrayList;
+import java.util.List;
+
+import com.vaadin.annotations.Widgetset;
+import com.vaadin.data.provider.DataProvider;
+import com.vaadin.data.provider.ListDataProvider;
+import com.vaadin.server.VaadinRequest;
+import com.vaadin.shared.ui.grid.HeightMode;
+import com.vaadin.tests.components.AbstractReindeerTestUI;
+import com.vaadin.ui.Alignment;
+import com.vaadin.ui.Button;
+import com.vaadin.ui.Grid;
+import com.vaadin.ui.GridLayout;
+import com.vaadin.ui.TabSheet;
+import com.vaadin.ui.VerticalLayout;
+
+@Widgetset("com.vaadin.DefaultWidgetSet")
+public class GridSizeChange extends AbstractReindeerTestUI {
+
+    private Grid<Integer> grid;
+    private List<Integer> data;
+    private ListDataProvider<Integer> dataProvider;
+    private int counter = 0;
+
+    @Override
+    protected void setup(VaadinRequest request) {
+        grid = new Grid<>();
+        data = new ArrayList<>();
+        for (int i = 0; i < 10; ++i) {
+            data.add(i);
+            ++counter;
+        }
+
+        dataProvider = DataProvider.ofCollection(data);
+        grid.setDataProvider(dataProvider);
+
+        // create column and fill rows
+        grid.addColumn(item -> "row_" + item).setCaption("Item");
+
+        // set height mode and height
+        grid.setHeightMode(HeightMode.ROW);
+        grid.setHeightByRows(10);
+        grid.setWidth(90, Unit.PIXELS);
+
+        // create a tabsheet with one tab and place grid inside
+        VerticalLayout tab = new VerticalLayout();
+        tab.setSpacing(false);
+        tab.setMargin(false);
+        TabSheet tabSheet = new TabSheet();
+        tabSheet.setWidthUndefined();
+        tabSheet.addTab(tab, "Tab");
+        tab.addComponent(grid);
+
+        GridLayout layout = new GridLayout(3, 2);
+        layout.setDefaultComponentAlignment(Alignment.TOP_CENTER);
+
+        layout.addComponent(new Button("Reduce height", e -> {
+            double newHeight = grid.getHeightByRows() - 1;
+            grid.setHeightByRows(newHeight);
+        }));
+
+        layout.addComponent(new Button("Remove row", e -> {
+            removeRow();
+            dataProvider.refreshAll();
+        }));
+
+        layout.addComponent(new Button("Reduce width", e -> {
+            grid.setWidth(grid.getWidth() - 30, Unit.PIXELS);
+        }));
+
+        layout.addComponent(new Button("Increase height", e -> {
+            double newHeight = grid.getHeightByRows() + 1;
+            grid.setHeightByRows(newHeight);
+        }));
+
+        layout.addComponent(new Button("Add row", e -> {
+            addRow();
+            dataProvider.refreshAll();
+        }));
+
+        layout.addComponent(new Button("Increase width", e -> {
+            grid.setWidth(grid.getWidth() + 30, Unit.PIXELS);
+        }));
+
+        addComponent(tabSheet);
+        addComponent(layout);
+
+        getLayout().setSpacing(true);
+    }
+
+    private void removeRow() {
+        data.remove(0);
+        dataProvider.refreshAll();
+    }
+
+    private void addRow() {
+        ++counter;
+        data.add(counter);
+        dataProvider.refreshAll();
+    }
+
+    @Override
+    protected String getTestDescription() {
+        return "Changing Grid size should resize the TabSheet accordingly "
+                + "even if scrollbar(s) appear or disappear.";
+    }
+}
diff --git a/uitest/src/test/java/com/vaadin/tests/components/grid/GridSizeChangeTest.java b/uitest/src/test/java/com/vaadin/tests/components/grid/GridSizeChangeTest.java
new file mode 100644
index 0000000000..3b8e485ed9
--- /dev/null
+++ b/uitest/src/test/java/com/vaadin/tests/components/grid/GridSizeChangeTest.java
@@ -0,0 +1,95 @@
+package com.vaadin.tests.components.grid;
+
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.number.IsCloseTo.closeTo;
+import static org.junit.Assert.assertEquals;
+
+import org.junit.Test;
+import org.openqa.selenium.WebElement;
+
+import com.vaadin.testbench.By;
+import com.vaadin.testbench.elements.ButtonElement;
+import com.vaadin.testbench.elements.GridElement;
+import com.vaadin.testbench.elements.TabSheetElement;
+import com.vaadin.tests.tb3.MultiBrowserTest;
+
+public class GridSizeChangeTest extends MultiBrowserTest {
+
+    private TabSheetElement tabSheet;
+    private GridElement grid;
+    private WebElement vScrollbar;
+    private WebElement hScrollbar;
+
+    @Test
+    public void scrollbarsTakenIntoAccountInSizeChanges() {
+        openTestURL();
+        tabSheet = $(TabSheetElement.class).first();
+        grid = $(GridElement.class).first();
+
+        vScrollbar = grid.findElement(By.className("v-grid-scroller-vertical"));
+        hScrollbar = grid
+                .findElement(By.className("v-grid-scroller-horizontal"));
+
+        // ensure no initial scrollbars
+        ensureVerticalScrollbar(false);
+        ensureHorizontalScrollbar(false);
+
+        assertGridWithinTabSheet();
+
+        $(ButtonElement.class).caption("Reduce height").first().click();
+        // more rows than height -> scrollbar
+
+        assertGridWithinTabSheet();
+        ensureVerticalScrollbar(true);
+
+        $(ButtonElement.class).caption("Remove row").first().click();
+        // height matches rows -> no scrollbar
+
+        assertGridWithinTabSheet();
+        ensureVerticalScrollbar(false);
+
+        $(ButtonElement.class).caption("Reduce width").first().click();
+        // column too wide -> scrollbar
+
+        assertGridWithinTabSheet();
+        ensureHorizontalScrollbar(true);
+
+        $(ButtonElement.class).caption("Increase width").first().click();
+        // column fits -> no scrollbar
+
+        assertGridWithinTabSheet();
+        ensureHorizontalScrollbar(false);
+
+        $(ButtonElement.class).caption("Add row").first().click();
+        // more rows than height -> scrollbar
+
+        assertGridWithinTabSheet();
+        ensureVerticalScrollbar(true);
+
+        $(ButtonElement.class).caption("Increase height").first().click();
+        // height matches rows -> no scrollbar
+
+        assertGridWithinTabSheet();
+        ensureVerticalScrollbar(false);
+    }
+
+    private void ensureVerticalScrollbar(boolean displayed) {
+        assertEquals(displayed ? "block" : "none",
+                vScrollbar.getCssValue("display"));
+    }
+
+    private void ensureHorizontalScrollbar(boolean displayed) {
+        assertEquals(displayed ? "block" : "none",
+                hScrollbar.getCssValue("display"));
+    }
+
+    private void assertGridWithinTabSheet() throws AssertionError {
+        // allow two pixel leeway
+        assertThat(
+                "Grid and TabSheet should always have the same bottom position, "
+                        + "not be offset by a scrollbar's thickness",
+                (double) grid.getLocation().getY() + grid.getSize().getHeight(),
+                closeTo(tabSheet.getLocation().getY()
+                        + tabSheet.getSize().getHeight(), 2));
+    }
+}