ChartDirector 6.0 (Ruby Edition)

Color Horizontal Bar Meters


          

This example demonstrates horizontal bar meters in various colors, with different color scales, and with title and value readout.

BaseMeter.addColorScale is used to create the color scales in the meters. The color scales are created by with different colors, different end point positions and different widths at the end points.

The title and value readout are created using BaseChart.addText. The value readout is configured to have a black background and a depressed border using Box.setBackground, and with rounded corners using Box.setRoundedCorners.

Source Code Listing

[Ruby On Rails Version - Controller] app/controllers/colorhbarmeter_controller.rb
require("chartdirector")

class ColorhbarmeterController < ApplicationController

    def index()
        @title = "Color Horizontal Bar Meters"
        @ctrl_file = File.expand_path(__FILE__)
        @noOfCharts = 6
        render :template => "templates/chartview"
    end

    #
    # Render and deliver the chart
    #
    def getchart()
        # This script can draw different charts depending on the chartIndex
        chartIndex = (params["img"]).to_i

        # The value to display on the meter
        value = 75.35

        # The background, border and bar colors of the meters
        bgColor = [0xbbddff, 0xccffcc, 0xffddff, 0xffffaa, 0xffdddd, 0xeeeeee]
        borderColor = [0x000088, 0x006600, 0x880088, 0xee6600, 0x880000, 0x666666]
        barColor = [0x0088ff, 0x00cc00, 0x8833dd, 0xff8800, 0xee3333, 0x888888]

        # Create a LinearMeter object of size 260 x 80 pixels with a 3-pixel thick rounded frame
        m = ChartDirector::LinearMeter.new(260, 80, bgColor[chartIndex], borderColor[chartIndex])
        m.setRoundedFrame(ChartDirector::Transparent)
        m.setThickFrame(3)

        # Set the scale region top-left corner at (18, 24), with size of 222 x 20 pixels. The scale
        # labels are located on the top (implies horizontal meter)
        m.setMeter(18, 24, 222, 20, ChartDirector::Top)

        # Set meter scale from 0 - 100, with a tick every 10 units
        m.setScale(0, 100, 10)

        if chartIndex % 4 == 0
            # Add a 5-pixel thick smooth color scale at y = 48 (below the meter scale)
            smoothColorScale = [0, 0x0000ff, 25, 0x0088ff, 50, 0x00ff00, 75, 0xdddd00, 100, 0xff0000
                ]
            m.addColorScale(smoothColorScale, 48, 5)
        elsif chartIndex % 4 == 1
            # Add a 5-pixel thick step color scale at y = 48 (below the meter scale)
            stepColorScale = [0, 0x00cc00, 50, 0xffdd00, 80, 0xff3333, 100]
            m.addColorScale(stepColorScale, 48, 5)
        elsif chartIndex % 4 == 2
            # Add a 5-pixel thick high/low color scale at y = 48 (below the meter scale)
            highLowColorScale = [0, 0x0000ff, 40, ChartDirector::Transparent, 60,
                ChartDirector::Transparent, 100, 0xff0000]
            m.addColorScale(highLowColorScale, 48, 5)
        else
            # Add a 5-pixel thick high only color scale at y = 48 (below the meter scale)
            highColorScale = [70, ChartDirector::Transparent, 100, 0xff0000]
            m.addColorScale(highColorScale, 48, 0, 48, 8)
        end

        # Add a bar from 0 to value with glass effect and 4 pixel rounded corners
        m.addBar(0, value, barColor[chartIndex], ChartDirector::glassEffect(
            ChartDirector::NormalGlare, ChartDirector::Top), 4)

        # Add a label right aligned to (243, 65) using 8pt Arial Bold font
        m.addText(243, 65, "Temperature C", "arialbd.ttf", 8, ChartDirector::TextColor,
            ChartDirector::Right)

        # Add a text box left aligned to (18, 65). Display the value using white (0xffffff) 8pt
        # Arial Bold font on a black (0x000000) background with depressed rounded border.
        t = m.addText(18, 65, m.formatValue(value, "2"), "arial.ttf", 8, 0xffffff,
            ChartDirector::Left)
        t.setBackground(0x000000, 0x000000, -1)
        t.setRoundedCorners(3)

        # Output the chart
        send_data(m.makeChart2(ChartDirector::PNG), :type => "image/png", :disposition => "inline")

    end

end

[Ruby On Rails Version - View] app/views/templates/chartview.html.erb
<html>
<body style="margin:5px 0px 0px 5px">

<!-- Title -->
<div style="font-size:18pt; font-family:verdana; font-weight:bold">
    <%= @title %>
</div>
<hr style="border:solid 1px #000080" />

<!-- Source Code Listing Link -->
<div style="font-size:9pt; font-family:verdana; margin-bottom:1.5em">
    <%= link_to "Source Code Listing", 
        :controller => "cddemo", :action => "viewsource",
        :ctrl_file => @ctrl_file, :view_file => File.expand_path(__FILE__) %>
</div>

<!-- Create one or more IMG tags to display the demo chart(s) -->
<% 0.upto(@noOfCharts - 1) do |i| %>
    <img src="<%= url_for(:action => "getchart", :img => i) %>">
<% end %>

</body>
</html>

[Command Line Version] rubydemo/colorhbarmeter.rb
#!/usr/bin/env ruby
require("chartdirector")

def createChart(chartIndex)

    # The value to display on the meter
    value = 75.35

    # The background, border and bar colors of the meters
    bgColor = [0xbbddff, 0xccffcc, 0xffddff, 0xffffaa, 0xffdddd, 0xeeeeee]
    borderColor = [0x000088, 0x006600, 0x880088, 0xee6600, 0x880000, 0x666666]
    barColor = [0x0088ff, 0x00cc00, 0x8833dd, 0xff8800, 0xee3333, 0x888888]

    # Create a LinearMeter object of size 260 x 80 pixels with a 3-pixel thick rounded frame
    m = ChartDirector::LinearMeter.new(260, 80, bgColor[chartIndex], borderColor[chartIndex])
    m.setRoundedFrame(ChartDirector::Transparent)
    m.setThickFrame(3)

    # Set the scale region top-left corner at (18, 24), with size of 222 x 20 pixels. The scale
    # labels are located on the top (implies horizontal meter)
    m.setMeter(18, 24, 222, 20, ChartDirector::Top)

    # Set meter scale from 0 - 100, with a tick every 10 units
    m.setScale(0, 100, 10)

    if chartIndex % 4 == 0
        # Add a 5-pixel thick smooth color scale at y = 48 (below the meter scale)
        smoothColorScale = [0, 0x0000ff, 25, 0x0088ff, 50, 0x00ff00, 75, 0xdddd00, 100, 0xff0000]
        m.addColorScale(smoothColorScale, 48, 5)
    elsif chartIndex % 4 == 1
        # Add a 5-pixel thick step color scale at y = 48 (below the meter scale)
        stepColorScale = [0, 0x00cc00, 50, 0xffdd00, 80, 0xff3333, 100]
        m.addColorScale(stepColorScale, 48, 5)
    elsif chartIndex % 4 == 2
        # Add a 5-pixel thick high/low color scale at y = 48 (below the meter scale)
        highLowColorScale = [0, 0x0000ff, 40, ChartDirector::Transparent, 60,
            ChartDirector::Transparent, 100, 0xff0000]
        m.addColorScale(highLowColorScale, 48, 5)
    else
        # Add a 5-pixel thick high only color scale at y = 48 (below the meter scale)
        highColorScale = [70, ChartDirector::Transparent, 100, 0xff0000]
        m.addColorScale(highColorScale, 48, 0, 48, 8)
    end

    # Add a bar from 0 to value with glass effect and 4 pixel rounded corners
    m.addBar(0, value, barColor[chartIndex], ChartDirector::glassEffect(ChartDirector::NormalGlare,
        ChartDirector::Top), 4)

    # Add a label right aligned to (243, 65) using 8pt Arial Bold font
    m.addText(243, 65, "Temperature C", "arialbd.ttf", 8, ChartDirector::TextColor,
        ChartDirector::Right)

    # Add a text box left aligned to (18, 65). Display the value using white (0xffffff) 8pt Arial
    # Bold font on a black (0x000000) background with depressed rounded border.
    t = m.addText(18, 65, m.formatValue(value, "2"), "arial.ttf", 8, 0xffffff, ChartDirector::Left)
    t.setBackground(0x000000, 0x000000, -1)
    t.setRoundedCorners(3)

    # Output the chart
    m.makeChart("colorhbarmeter%s.png" % chartIndex)
end

createChart(0)
createChart(1)
createChart(2)
createChart(3)
createChart(4)
createChart(5)