require("chartdirector")
class LinearzonemeterController < ApplicationController
def index()
@title = "Linear Zone Meter"
@ctrl_file = File.expand_path(__FILE__)
@noOfCharts = 1
render :template => "templates/chartview"
end
#
# Render and deliver the chart
#
def getchart()
# The value to display on the meter
value = 85
# Create an LinearMeter object of size 210 x 45 pixels, using silver background
# with a 2 pixel black 3D depressed border.
m = ChartDirector::LinearMeter.new(210, 45, ChartDirector::silverColor(), 0, -2)
# Set the scale region top-left corner at (5, 5), with size of 200 x 20 pixels.
# The scale labels are located on the bottom (implies horizontal meter)
m.setMeter(5, 5, 200, 20, ChartDirector::Bottom)
# Set meter scale from 0 - 100
m.setScale(0, 100)
# Add a title at the bottom of the meter with a 1 pixel raised 3D border
m.addTitle2(ChartDirector::Bottom, "Battery Level", "arialbd.ttf", 8
).setBackground(ChartDirector::Transparent, -1, 1)
# Set 3 zones of different colors to represent Good/Weak/Bad data ranges
m.addZone(50, 100, 0x99ff99, "Good")
m.addZone(20, 50, 0xffff66, "Weak")
m.addZone(0, 20, 0xffcccc, "Bad")
# Add empty labels (just need the ticks) at 0/20/50/80 as separators for zones
m.addLabel(0, " ")
m.addLabel(20, " ")
m.addLabel(50, " ")
m.addLabel(100, " ")
# Add a semi-transparent blue (800000ff) pointer at the specified value, using
# triangular pointer shape
m.addPointer(value, 0x800000ff).setShape(ChartDirector::TriangularPointer)
# output the chart
send_data(m.makeChart2(ChartDirector::PNG), :type => "image/png",
:disposition => "inline")
end
end |