Add missing HasEnabled implementation to HighchartsWidget.java (#600)

- Add missing HasEnabled implementation to HighchartsWidget.java
- Add missing styles for disabled Charts component

Fixes: #427

addon/src/main/java/com/vaadin/addon/charts/client/ui/HighchartWidget.java

@@ -21,13 +21,16 @@
 import com.google.gwt.core.client.Scheduler;
 import com.google.gwt.core.client.Scheduler.ScheduledCommand;
 import com.google.gwt.dom.client.Document;
+import com.google.gwt.user.client.ui.HasEnabled;
 import com.google.gwt.user.client.ui.Widget;
 import com.vaadin.addon.charts.client.HighchartsScriptLoader;
 import com.vaadin.client.BrowserInfo;
+import com.vaadin.client.StyleConstants;
 
-public class HighchartWidget extends Widget {
+public class HighchartWidget extends Widget implements HasEnabled {
 
     private HighchartJsOverlay jsOverlay;
+    private boolean enabled;
 
     public HighchartWidget() {
         HighchartsScriptLoader.ensureInjected();
@@ -207,4 +210,17 @@ public int getXAxisIndex(HighchartAxis axis) {
     public int getNumberOfSeries() {
         return jsOverlay.getSeries().length();
     }
+
+    @Override
+    public boolean isEnabled() {
+        return enabled;
+    }
+
+    @Override
+    public void setEnabled(boolean enabled) {
+        if (this.enabled != enabled) {
+            this.enabled = enabled;
+            setStyleName(StyleConstants.DISABLED, !enabled);
+        }
+    }
 }

addon/src/main/resources/com/vaadin/addon/charts/Widgetset.gwt.xml

@@ -26,4 +26,6 @@
 	<inherits name="com.vaadin.DefaultWidgetSet" />
 	<inherits name="com.google.gwt.json.JSON" />
 
+	<!-- Widget styles in public -directory -->
+	<stylesheet src="charts/styles.css"/>	
 </module>

addon/src/main/resources/com/vaadin/addon/charts/public/charts/styles.css

@@ -0,0 +1,6 @@
+.v-disabled {
+    .vaadin-chart {
+        pointer-events: none;
+        opacity: 70%;
+    }
+}

examples/src/main/java/com/vaadin/addon/charts/examples/columnandbar/BarWithDisabledState.java

@@ -0,0 +1,29 @@
+package com.vaadin.addon.charts.examples.columnandbar;
+
+import com.vaadin.addon.charts.examples.SkipFromDemo;
+import com.vaadin.ui.Button;
+import com.vaadin.ui.Component;
+
+@SuppressWarnings("serial")
+@SkipFromDemo
+public class BarWithDisabledState extends BasicBarNoTitle {
+
+    private Component chart;
+
+    @Override
+    protected Component getChart() {
+        chart = super.getChart();
+        chart.setId("bar-with-disabled-state");
+
+        return chart;
+    }
+
+    @Override
+    protected void setup() {
+        super.setup();
+
+        Button button = new Button("toggle enabled", e -> chart.setEnabled(!chart.isEnabled()));
+        button.setId("disable-button");
+        addComponent(button);
+    }
+}

integration-tests/src/test/java/com/vaadin/addon/charts/testbenchtests/BarWithDisabledStateTBTest.java

@@ -0,0 +1,47 @@
+package com.vaadin.addon.charts.testbenchtests;
+
+import java.io.IOException;
+
+import org.junit.Assert;
+import org.junit.Test;
+import org.openqa.selenium.By;
+import org.openqa.selenium.WebElement;
+
+import com.vaadin.addon.charts.examples.columnandbar.BarWithDisabledState;
+import com.vaadin.client.StyleConstants;
+import com.vaadin.testbench.elements.ButtonElement;
+
+public class BarWithDisabledStateTBTest extends AbstractParallelTest {
+
+    @Test
+    public void test() throws IOException, AssertionError {
+        driver.get(getTestUrl());
+
+        waitForVaadin();
+
+        WebElement chart = findElement(By.id("bar-with-disabled-state"));
+
+        ButtonElement disableButton = $(ButtonElement.class).id("disable-button");
+        disableButton.click();
+        waitForVaadin();
+
+        Assert.assertTrue(chart.getAttribute("class").contains(StyleConstants.DISABLED));
+
+        disableButton.click();
+        waitForVaadin();
+
+        Assert.assertFalse(chart.getAttribute("class").contains(StyleConstants.DISABLED));
+
+    }
+
+    @Override
+    protected String getTestViewName() {
+        return BarWithDisabledState.class.getSimpleName();
+    }
+
+    @Override
+    protected String getPackageName() {
+        return "columnandbar";
+    }
+
+}