GWT Google Charts 基本折线图

以下是基本折线图的示例。

我们已经在《GWT Google Charts 入门程序》章节中看到了用于绘制图表的基本步骤。现在，让我们看一个基本折线图的例子。

GWT Google Charts 基本折线图 配置

我们使用LineChart类来显示基本折线图。

// Line chart
LineChart chart = new LineChart();

GWT Google Charts 基本折线图 示例

package com.yiidian.helloWorld.client;

import com.google.gwt.core.client.EntryPoint;
import com.google.gwt.user.client.ui.*;
import com.google.gwt.user.client.rpc.AsyncCallback;
import com.google.gwt.user.client.DOM;
import com.google.gwt.event.dom.client.ClickHandler;
import com.google.gwt.event.dom.client.ClickEvent;
import com.googlecode.gwt.charts.client.ChartLoader;
import com.googlecode.gwt.charts.client.ChartPackage;
import com.googlecode.gwt.charts.client.ColumnType;
import com.googlecode.gwt.charts.client.DataTable;
import com.googlecode.gwt.charts.client.corechart.*;
import com.googlecode.gwt.charts.client.options.*;
import com.googlecode.gwt.charts.client.util.ChartHelper;

public class HelloWorld implements EntryPoint {
    private LineChart chart;

    private void initialize() {
        ChartLoader chartLoader = new ChartLoader(ChartPackage.CORECHART);
        chartLoader.loadApi(new Runnable() {
            public void run() {
                // Create and attach the chart
                chart = new LineChart();
                RootPanel.get().add(chart);
                draw();
            }
        });
    }
    private void draw() {
        // Prepare the data
        DataTable data = DataTable.create();
        data.addColumn(ColumnType.STRING, "Month");
        data.addColumn(ColumnType.NUMBER, "Tokyo");
        data.addColumn(ColumnType.NUMBER, "New York");
        data.addColumn(ColumnType.NUMBER, "Berlin");
        data.addColumn(ColumnType.NUMBER, "Berlin");

        data.addRow("Jan",  7.0, -0.2, -0.9, 3.9);
        data.addRow("Feb",  6.9, 0.8, 0.6, 4.2);
        data.addRow("Mar",  9.5,  5.7, 3.5, 5.7);
        data.addRow("Apr",  14.5, 11.3, 8.4, 8.5);
        data.addRow("May",  18.2, 17.0, 13.5, 11.9);
        data.addRow("Jun",  21.5, 22.0, 17.0, 15.2);
        data.addRow("Jul",  25.2, 24.8, 18.6, 17.0);
        data.addRow("Aug",  26.5, 24.1, 17.9, 16.6);
        data.addRow("Sep",  23.3, 20.1, 14.3, 14.2);
        data.addRow("Oct",  18.3, 14.1, 9.0, 10.3);
        data.addRow("Nov",  13.9,  8.6, 3.9, 6.6);
        data.addRow("Dec",  9.6,  2.5,  1.0, 4.8);

        // Set options
        LineChartOptions options = LineChartOptions.create();
        options.setTitle("Average Temperatures of Cities");
        options.setHAxis(HAxis.create("Month"));
        options.setVAxis(VAxis.create("Temperature"));

        // Draw the chart
        chart.draw(data,options);
        chart.setWidth("600px");
        chart.setHeight("400px");
    }
    public void onModuleLoad() {
        initialize();
    }
}

输出结果为：