TreeTest.java

package com.vaadin.tests.components;

import org.junit.Assert;
import org.junit.Test;

import com.vaadin.data.HierarchyData;
import com.vaadin.data.provider.InMemoryHierarchicalDataProvider;
import com.vaadin.event.CollapseEvent;
import com.vaadin.event.CollapseEvent.CollapseListener;
import com.vaadin.event.ExpandEvent;
import com.vaadin.event.ExpandEvent.ExpandListener;
import com.vaadin.ui.Tree;

public class TreeTest {

    private static class TreeCollapseExpandListener
            implements ExpandListener<String>, CollapseListener<String> {

        private boolean collapsed = false;
        private boolean expanded = false;
        private final Tree<String> tree;

        public TreeCollapseExpandListener(Tree<String> tree) {
            this.tree = tree;
        }

        @Override
        public void itemCollapse(CollapseEvent<String> event) {
            Assert.assertEquals("Source component was incorrect", tree,
                    event.getComponent());
            Assert.assertFalse("Multiple collapse events", collapsed);
            collapsed = true;
        }

        @Override
        public void itemExpand(ExpandEvent<String> event) {
            Assert.assertEquals("Source component was incorrect", tree,
                    event.getComponent());
            Assert.assertFalse("Multiple expand events", expanded);
            expanded = true;
        }

        public boolean isExpanded() {
            return expanded;
        }

        public boolean isCollapsed() {
            return collapsed;
        }
    }

    @Test
    public void event_source_is_tree() {
        Tree<String> tree = new Tree<>();
        HierarchyData<String> hierarchyData = new HierarchyData<>();
        hierarchyData.addItem(null, "Foo");
        hierarchyData.addItem("Foo", "Bar");
        hierarchyData.addItem("Foo", "Baz");
        tree.setDataProvider(
                new InMemoryHierarchicalDataProvider<>(hierarchyData));

        TreeCollapseExpandListener listener = new TreeCollapseExpandListener(
                tree);
        tree.addExpandListener(listener);
        tree.addCollapseListener(listener);

        Assert.assertFalse(listener.isExpanded());
        tree.expand("Foo");
        Assert.assertTrue("Expand event not fired", listener.isExpanded());
        Assert.assertFalse(listener.isCollapsed());
        tree.collapse("Foo");
        Assert.assertTrue("Collapse event not fired", listener.isCollapsed());
    }

}