ChartJs.java

package org.dashbuilder.renderer.chartjs.lib;

import com.google.gwt.dom.client.Document;
import com.google.gwt.dom.client.ScriptElement;
import org.dashbuilder.renderer.chartjs.lib.resources.Resources;

import com.google.gwt.core.client.GWT;


/**
 * Utility class which helps to inject native chart.js code into browser
 */
public final class ChartJs {

	private static boolean injected = false;
	
	/**
	 * Method injecting native chart.js code into the browser<br/>
	 * In case code already been injected do nothing
	 */
	public static void ensureInjected(){ //TODO: do real injection (lazy loading)
		if(injected)
			return;
		Resources res = GWT.create(Resources.class);
		String source = res.chartJsSource().getText();
        ScriptElement scriptElement = Document.get().createScriptElement();
        scriptElement.setId("_chartjs");
        scriptElement.setInnerText(source);
        Document.get().getBody().appendChild(scriptElement);
		injected = true;
	}
}