ChartDirector 6.1 (Java Edition)

White Round Meters


          

This example demonstrates round meters with a soft white background and a silver border.

The white background in this example is actually a radial gradient. It is fully white at the center, changing to light grey at the border. This creates a "softer" white effect. The radial gradient is created using AngularMeter.relativeRadialGradient.

The silver border effect is achieved by using AngularMeter.relativeLinearGradient to create a gradient consisting of varying levels of grey. The gradient is used as the fill color of the border ring created using AngularMeter.addRing. The edge color of the ring is set to grey to make it easier to distinguish from the white background.

Source Code Listing

[JSP Version] jspdemo/whiteroundmeter.jsp
<%@page import="ChartDirector.*" %>
<%@page import="javax.servlet.http.*" %>
<%!
// Function to create the demo charts
String createChart(HttpServletRequest request, int chartIndex)
{
    // The value to display on the meter
    double value = 72.3;

    // Create an AngularMeter object of size 250 x 250 pixels with transparent background
    AngularMeter m = new AngularMeter(250, 250, Chart.Transparent);

    // Set the default text and line colors to dark grey (0x333333)
    m.setColor(Chart.TextColor, 0x333333);
    m.setColor(Chart.LineColor, 0x333333);

    // Demonstration two different meter scale angles
    if (chartIndex % 2 == 0) {
        // Center at (125, 125), scale radius = 111 pixels, scale angle -140 to +140 degrees
        m.setMeter(125, 125, 109, -140, 140);
    } else {
        // Center at (125, 125), scale radius = 111 pixels, scale angle -180 to +90 degrees
         m.setMeter(125, 125, 109, -180, 90);
    }

    // Add a black (0x000000) circle with radius 123 pixels as background
    m.addRing(0, 123, 0x000000);

    // Background gradient color from white (0xffffff) at the center to light grey (0xdddddd) at the
    // border
    double[] bgGradient = {0, 0xffffff, 0.75, 0xeeeeee, 1, 0xdddddd};
    // Add circle with radius 123 pixels as background using the background gradient
    m.addRing(0, 123, m.relativeRadialGradient(bgGradient, 123));

    // Gradient color for the border to make it silver-like
    double[] ringGradient = {1, 0x999999, 0.5, 0xdddddd, 0, 0xffffff, -0.5, 0xdddddd, -1, 0x999999};
    // Add a ring between radii 114 and 123 pixels using the silver gradient with a light grey
    // (0xbbbbbb) edge as the meter border
    m.addRing(114, 123, m.relativeLinearGradient(ringGradient, 45, 123), 0xbbbbbb);

    // Meter scale is 0 - 100, with major/minor/micro ticks every 10/5/1 units
    m.setScale(0, 100, 10, 5, 1);

    // Set the scale label style to 15pt Arial Italic. Set the major/minor/micro tick lengths to
    // 12/9/6 pixels pointing inwards, and their widths to 2/1/1 pixels.
    m.setLabelStyle("Arial Italic", 15);
    m.setTickLength(-12, -9, -6);
    m.setLineWidth(0, 2, 1, 1);

    // Demostrate different types of color scales and putting them at different positions
    double[] smoothColorScale = {0, 0x3333ff, 25, 0x0088ff, 50, 0x00ff00, 75, 0xdddd00, 100,
        0xff0000};
    double[] stepColorScale = {0, 0x00cc00, 60, 0xffdd00, 80, 0xee0000, 100};
    double[] highLowColorScale = {0, 0x00ff00, 70, Chart.Transparent, 100, 0xff0000};

    if (chartIndex == 0) {
        // Add the smooth color scale at the default position
        m.addColorScale(smoothColorScale);
    } else if (chartIndex == 1) {
        // Add the smooth color scale starting at radius 62 with zero width and ending at radius 40
        // with 22 pixels outer width
        m.addColorScale(smoothColorScale, 62, 0, 40, 22);
    } else if (chartIndex == 2) {
        // Add the smooth color scale starting at radius 109 with zero width and ending at radius
        // 109 with 12 pixels inner width
        m.addColorScale(smoothColorScale, 109, 0, 109, -12);
    } else if (chartIndex == 3) {
        // Add the high/low color scale at the default position
        m.addColorScale(highLowColorScale);
    } else if (chartIndex == 4) {
        // Add the smooth color scale at radius 44 with 16 pixels outer width
        m.addColorScale(smoothColorScale, 44, 16);
    } else {
        // Add the step color scale at the default position
        m.addColorScale(stepColorScale);
    }

    // Add a text label centered at (125, 175) with 15pt Arial Italic font
    m.addText(125, 175, "CPU", "Arial Italic", 15, Chart.TextColor, Chart.Center);

    // Add a readout to some of the charts as demonstration
    if (chartIndex == 0 || chartIndex == 2) {
        // Put the value label center aligned at (125, 232), using white (0xffffff) 14pt Arial font
        // on a dark grey (0x222222) background. Set box width to 50 pixels with 5 pixels rounded
        // corners.
        TextBox t = m.addText(125, 232, m.formatValue(value,
            "<*block,width=50,halign=center*>{value|1}"), "Arial", 14, 0xffffff, Chart.BottomCenter)
            ;
        t.setBackground(0x222222);
        t.setRoundedCorners(5);
    }

    // Add a red (0xff0000) pointer at the specified value
    m.addPointer2(value, 0xff0000);

    // Output the chart
    return m.makeSession(request, "chart" + chartIndex);
}
%>
<%
String chart0URL = createChart(request, 0);
String chart1URL = createChart(request, 1);
String chart2URL = createChart(request, 2);
String chart3URL = createChart(request, 3);
String chart4URL = createChart(request, 4);
String chart5URL = createChart(request, 5);
%>
<html>
<body style="margin:5px 0px 0px 5px">
<div style="font-size:18pt; font-family:verdana; font-weight:bold">
    White Round Meters
</div>
<hr color="#000080">
<div style="font-size:10pt; font-family:verdana; margin-bottom:1.5em">
    <a href="viewsource.jsp?file=<%=request.getServletPath()%>">View Source Code</a>
</div>
<img src='<%=response.encodeURL("getchart.jsp?"+chart0URL)%>'>
<img src='<%=response.encodeURL("getchart.jsp?"+chart1URL)%>'>
<img src='<%=response.encodeURL("getchart.jsp?"+chart2URL)%>'>
<img src='<%=response.encodeURL("getchart.jsp?"+chart3URL)%>'>
<img src='<%=response.encodeURL("getchart.jsp?"+chart4URL)%>'>
<img src='<%=response.encodeURL("getchart.jsp?"+chart5URL)%>'>
</body>
</html>

[Java Version] javademo/whiteroundmeter.java
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import ChartDirector.*;

public class whiteroundmeter implements DemoModule
{
    //Name of demo program
    public String toString() { return "White Round Meters"; }

    //Number of charts produced in this demo
    public int getNoOfCharts() { return 6; }

    //Main code for creating charts
    public void createChart(ChartViewer viewer, int chartIndex)
    {
        // The value to display on the meter
        double value = 72.3;

        // Create an AngularMeter object of size 250 x 250 pixels with transparent background
        AngularMeter m = new AngularMeter(250, 250, Chart.Transparent);

        // Set the default text and line colors to dark grey (0x333333)
        m.setColor(Chart.TextColor, 0x333333);
        m.setColor(Chart.LineColor, 0x333333);

        // Demonstration two different meter scale angles
        if (chartIndex % 2 == 0) {
            // Center at (125, 125), scale radius = 111 pixels, scale angle -140 to +140 degrees
            m.setMeter(125, 125, 109, -140, 140);
        } else {
            // Center at (125, 125), scale radius = 111 pixels, scale angle -180 to +90 degrees
             m.setMeter(125, 125, 109, -180, 90);
        }

        // Add a black (0x000000) circle with radius 123 pixels as background
        m.addRing(0, 123, 0x000000);

        // Background gradient color from white (0xffffff) at the center to light grey (0xdddddd) at
        // the border
        double[] bgGradient = {0, 0xffffff, 0.75, 0xeeeeee, 1, 0xdddddd};
        // Add circle with radius 123 pixels as background using the background gradient
        m.addRing(0, 123, m.relativeRadialGradient(bgGradient, 123));

        // Gradient color for the border to make it silver-like
        double[] ringGradient = {1, 0x999999, 0.5, 0xdddddd, 0, 0xffffff, -0.5, 0xdddddd, -1,
            0x999999};
        // Add a ring between radii 114 and 123 pixels using the silver gradient with a light grey
        // (0xbbbbbb) edge as the meter border
        m.addRing(114, 123, m.relativeLinearGradient(ringGradient, 45, 123), 0xbbbbbb);

        // Meter scale is 0 - 100, with major/minor/micro ticks every 10/5/1 units
        m.setScale(0, 100, 10, 5, 1);

        // Set the scale label style to 15pt Arial Italic. Set the major/minor/micro tick lengths to
        // 12/9/6 pixels pointing inwards, and their widths to 2/1/1 pixels.
        m.setLabelStyle("Arial Italic", 15);
        m.setTickLength(-12, -9, -6);
        m.setLineWidth(0, 2, 1, 1);

        // Demostrate different types of color scales and putting them at different positions
        double[] smoothColorScale = {0, 0x3333ff, 25, 0x0088ff, 50, 0x00ff00, 75, 0xdddd00, 100,
            0xff0000};
        double[] stepColorScale = {0, 0x00cc00, 60, 0xffdd00, 80, 0xee0000, 100};
        double[] highLowColorScale = {0, 0x00ff00, 70, Chart.Transparent, 100, 0xff0000};

        if (chartIndex == 0) {
            // Add the smooth color scale at the default position
            m.addColorScale(smoothColorScale);
        } else if (chartIndex == 1) {
            // Add the smooth color scale starting at radius 62 with zero width and ending at radius
            // 40 with 22 pixels outer width
            m.addColorScale(smoothColorScale, 62, 0, 40, 22);
        } else if (chartIndex == 2) {
            // Add the smooth color scale starting at radius 109 with zero width and ending at
            // radius 109 with 12 pixels inner width
            m.addColorScale(smoothColorScale, 109, 0, 109, -12);
        } else if (chartIndex == 3) {
            // Add the high/low color scale at the default position
            m.addColorScale(highLowColorScale);
        } else if (chartIndex == 4) {
            // Add the smooth color scale at radius 44 with 16 pixels outer width
            m.addColorScale(smoothColorScale, 44, 16);
        } else {
            // Add the step color scale at the default position
            m.addColorScale(stepColorScale);
        }

        // Add a text label centered at (125, 175) with 15pt Arial Italic font
        m.addText(125, 175, "CPU", "Arial Italic", 15, Chart.TextColor, Chart.Center);

        // Add a readout to some of the charts as demonstration
        if (chartIndex == 0 || chartIndex == 2) {
            // Put the value label center aligned at (125, 232), using white (0xffffff) 14pt Arial
            // font on a dark grey (0x222222) background. Set box width to 50 pixels with 5 pixels
            // rounded corners.
            TextBox t = m.addText(125, 232, m.formatValue(value,
                "<*block,width=50,halign=center*>{value|1}"), "Arial", 14, 0xffffff,
                Chart.BottomCenter);
            t.setBackground(0x222222);
            t.setRoundedCorners(5);
        }

        // Add a red (0xff0000) pointer at the specified value
        m.addPointer2(value, 0xff0000);

        // Output the chart
        viewer.setChart(m);
    }

    //Allow this module to run as standalone program for easy testing
    public static void main(String[] args)
    {
        //Instantiate an instance of this demo module
        DemoModule demo = new whiteroundmeter();

        //Create and set up the main window
        JFrame frame = new JFrame(demo.toString());
        frame.addWindowListener(new WindowAdapter() {
            public void windowClosing(WindowEvent e) {System.exit(0);} });
        frame.getContentPane().setBackground(Color.white);
        frame.getContentPane().setLayout(new FlowLayout(FlowLayout.LEFT));
        frame.setSize(800, 450);

        // Create the charts and put them in the content pane
        for (int i = 0; i < demo.getNoOfCharts(); ++i)
        {
            ChartViewer viewer = new ChartViewer();
            demo.createChart(viewer, i);
            frame.getContentPane().add(viewer);
        }

        // Display the window
        frame.setVisible(true);
    }
}