PullMonkey Blog


05 Jan

Open Flash Chart II - X Axis Date and Time


I was asked how to display date and time for the x axis as seen in this teethgrinder example - So here it goes.

Here is the graph we are after in this example:

More Open Flash Chart II examples.

And here is the code (the controller):

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class TestItController < ApplicationController
  def index
    @graph = open_flash_chart_object(550,300,"/test_it/chart")
  end
  def chart
    data1 = []
    data2 = []
    year = Time.now.year

    31.times do |i|
      x = "#{year}-1-#{i+1}".to_time.to_i
      y = (Math.sin(i+1) * 2.5) + 10

      data1 << ScatterValue.new(x,y)
      data2 << (Math.cos(i+1) * 1.9) + 4
    end

    dot = HollowDot.new
    dot.size = 3
    dot.halo_size = 2
    dot.tooltip = "#date:d M y#<br>Value: #val#"

    line = ScatterLine.new("#DB1750", 3)
    line.values = data1
    line.default_dot_style = dot

    x = XAxis.new
    x.set_range("#{year}-1-1".to_time.to_i, "#{year}-1-31".to_time.to_i)
    x.steps = 86400

    labels = XAxisLabels.new
    labels.text = "#date: l jS, M Y#"
    labels.steps = 86400
    labels.visible_steps = 2
    labels.rotate = 90

    x.labels = labels

    y = YAxis.new
    y.set_range(0,15,5)

    chart = OpenFlashChart.new
    title = Title.new(data2.size)

    chart.title = title
    chart.add_element(line)
    chart.x_axis = x
    chart.y_axis = y

    render :text => chart, :layout => false
  end
end

And in your view (index.html.erb):

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<script type="text/javascript" src="/javascripts/swfobject.js"></script>
<%= @graph %>

Good Luck!