ChartDirector Ver 5.0 (Ruby Edition)

Stacked Bar Chart




This example demonstrates creating a stacked bar chart, completed with bar labels and legend box.

The key features demonstrated in this example are:

For bar labels, Layer.setDataLabelStyle and Layer.setAggregateLabelStyle control the styles (fonts, colors, backgrounds, etc), while Layer.setDataLabelFormat and Layer.setAggregateLabelFormat control the formats (the contents of the label, number of decimal points in numbers, etc). You may also add custom labels to the bars using Layer.addCustomDataLabel and Layer.addCustomAggregateLabel and Layer.addCustomGroupLabel.

Source Code Listing

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

class StackedbarController < ApplicationController

    def index()
        @title = "Stacked Bar Chart"
        @ctrl_file = File.expand_path(__FILE__)
        @noOfCharts = 1
        render :template => "templates/chartview"
    end

    #
    # Render and deliver the chart
    #
    def getchart()
        # The data for the bar chart
        data0 = [100, 125, 245, 147, 67]
        data1 = [85, 156, 179, 211, 123]
        data2 = [97, 87, 56, 267, 157]

        # The labels for the bar chart
        labels = ["Mon", "Tue", "Wed", "Thu", "Fri"]

        # Create a XYChart object of size 500 x 320 pixels
        c = ChartDirector::XYChart.new(500, 320)

        # Set the plotarea at (100, 40) and of size 280 x 240 pixels
        c.setPlotArea(100, 40, 280, 240)

        # Add a legend box at (400, 100)
        c.addLegend(400, 100)

        # Add a title to the chart using 14 points Times Bold Itatic font
        c.addTitle("Weekday Network Load", "timesbi.ttf", 14)

        # Add a title to the y axis. Draw the title upright (font angle = 0)
        c.yAxis().setTitle("Average\nWorkload\n(MBytes\nPer Hour)").setFontAngle(0)

        # Set the labels on the x axis
        c.xAxis().setLabels(labels)

        # Add a stacked bar layer and set the layer 3D depth to 8 pixels
        layer = c.addBarLayer2(ChartDirector::Stack, 8)

        # Add the three data sets to the bar layer
        layer.addDataSet(data0, 0xff8080, "Server # 1")
        layer.addDataSet(data1, 0x80ff80, "Server # 2")
        layer.addDataSet(data2, 0x8080ff, "Server # 3")

        # Enable bar label for the whole bar
        layer.setAggregateLabelStyle()

        # Enable bar label for each segment of the stacked bar
        layer.setDataLabelStyle()

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

end

[Ruby On Rails Version - View] app/views/templates/chartview.rhtml
<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/stackedbar.rb
#!/usr/bin/env ruby
require("chartdirector")

# The data for the bar chart
data0 = [100, 125, 245, 147, 67]
data1 = [85, 156, 179, 211, 123]
data2 = [97, 87, 56, 267, 157]

# The labels for the bar chart
labels = ["Mon", "Tue", "Wed", "Thu", "Fri"]

# Create a XYChart object of size 500 x 320 pixels
c = ChartDirector::XYChart.new(500, 320)

# Set the plotarea at (100, 40) and of size 280 x 240 pixels
c.setPlotArea(100, 40, 280, 240)

# Add a legend box at (400, 100)
c.addLegend(400, 100)

# Add a title to the chart using 14 points Times Bold Itatic font
c.addTitle("Weekday Network Load", "timesbi.ttf", 14)

# Add a title to the y axis. Draw the title upright (font angle = 0)
c.yAxis().setTitle("Average\nWorkload\n(MBytes\nPer Hour)").setFontAngle(0)

# Set the labels on the x axis
c.xAxis().setLabels(labels)

# Add a stacked bar layer and set the layer 3D depth to 8 pixels
layer = c.addBarLayer2(ChartDirector::Stack, 8)

# Add the three data sets to the bar layer
layer.addDataSet(data0, 0xff8080, "Server # 1")
layer.addDataSet(data1, 0x80ff80, "Server # 2")
layer.addDataSet(data2, 0x8080ff, "Server # 3")

# Enable bar label for the whole bar
layer.setAggregateLabelStyle()

# Enable bar label for each segment of the stacked bar
layer.setDataLabelStyle()

# Output the chart
c.makeChart("stackedbar.png")