Easy-to-follow video tutorials help you learn software, creative, and business skills.Become a member
We have already see one kind of graphical presentation of data in the video mapping with the Gmap Module. But what about when you want to present non-locational data? For that you need a chart and fortunately Drupal has a Module set up exactly for that. It's called un-surprisingly the Charts Module. By itself it doesn't actually charts, rather it works together with Views to prepare and deliver data in your Drupal site so that other services can then into graphical chart form. As I say this, this Module includes hooks to 3 sets of services, Google Charts, which simply turns your data into a graphic which gets send back to your site. Open Flash Chart, which is a Flash-based solution with some really neat features. And Fusion Charts, a commercial solution.
We are only going to look at the first two of these. That is, Google Charts and Open Flash Chart. Our task is to get a visual representation of which states are home to the most family members. As I have done a few times in this course, I have to warn you about the quality of the Modules involved, they work but as I'm recording this video in March 2009, they are still very immature and very, very tricky. I'll walk you through them of course and hope that it all improves by the time that this video is released. The unpredictable world of software development, particularly volunteer software development.
Our first step is to enable some Modules. We go to Administer, Site building, and Modules. Once there, scroll down until you come to the Chart section, we are going to enable only two, Charts and Google. I should warn you again, at the moment that I'm recording this, this Module is so immature that if you turn on some of these other Modules without having other certain pieces installed, it could actually crash your site. So Charts and Google, at least you know that you will be safe. Scrolling down, we click Save configuration. We'll come back to the Modules later and I'll explain how you can turn them on safely. After you have turned on the Modules, you might naturally then head over to the Views administrative interface and start setting up your view.
Unfortunately, again the Charts Module is somewhat immature and fails to warn you that you first need to configure the Module itself, if it was working correctly it would normally tell you here but instead you only find out if you happen to go the Administer page and then you see this error that you need to something. We click on the status report to see what. Now it tells us we have to go to the settings page to set up Charts. If we had enabled more than just the Google Chart plug-in, that is the Open Flash Chart, or the other one, we would see that in this pop-down menu here. But if it's just Google, that's fine.
We can change the width and height of the Chart and as we scroll down we can change the color of the Chart. But again it's not working quite the way you expect. Normally, you would click in here and then click over here on the color wheel to change the color, but it doesn't actually work yet. So, we'll just change it manually. If you would like to find out what colors you are actually using, you could use a separate program such as Photoshop and look at a Hex Chart. We'll just change this to 00033, just so we can see a different color, and save settings. After you have saved this once, you then have a choice of what Chart type to use, by default its set to Horizontal Bar 2D. We are actually going to be aggregating the information of how many people live in each state and a Pie Chart is more appropriate for that.
Graphing data is a complex field and there are a lot of potential gotchas one of them is choosing the wrong Chart type. Make sure that you check you data when you are done and look at the graph to compare and make sure that you have chosen one that actually makes sense. We will take Pie 2D, and scroll down and save settings. Good. Now we are actually ready to go and build our View. One nice thing about the Module I'll say is that it gives you little preview so you can get a sense of what the Chart will look like with your data. But we'll go on to our View. I go to Administer, Site building, and Views. Once there, I add a view. I'm going to call this chart_of_households. I'll call the description, Chart of households.
As usual, we won't add a tag and it's going to be a view of Nodes. Scroll down and click Next. Here, I'll do my usual default things that I do with Views. I'll set up my Filters, so it only shows published nodes of the type household. Scroll down, choose the Node group, scroll down again, Published and Type. Click Add, Yes Published and type is Household, and Update. I am also going to make sure that we see everything that we want, all of the nodes, so I change the Items to display from 10 to 0. And you could imagine, if you have many states in there, all 50 states with people living in them, then you would only get the first ten that would lead to some very strange results.
We click on Update, and finally, add some Fields. The criterion we are looking for, remember is states. As it happens, the Location Module calls them Provinces to be a little more international. We find it by choosing the Group Location and scrolling down to Province. Accept that choice, click Add and then make our usual changes. I am going to take away the Label, for example, and look at all the other ones. One of the interesting ones here is you can choose between the Province name, that is, California for example, or the Province code. In this case it would just be CA. I'll leave it on the name and click Update. There, we now have a list of all of our households and as you can see three are in California and one each are in three other states. But we want to see this as a Chart. As it happens, that's the easy part of the equation.
We simply scroll up, go to our Style and change it from Unformatted to Chart. Scroll down, click Update and set our options. Let's scroll up to see all of those options. We are asked once again what our format should be, and again, be sure that you compare your data to the finished chart to make sure you chose the right one. We can change the height, the width, the Background color, we are going to leave all of those alone for right now. But I do want to discuss this Conversion type. Let's leave it as it is, Display numbers from every row, and click Update. We actually get an error because of the type of data that we are using. We don't actually want to show the number California. It's not a number. And so of course, we get this warning. Ideally, we would get a friendly warning than this big red box with lots of code in it, but that's the way the Charts Module works.
Instead, we want to go up and edit our Style, scroll down again and change it so it, Displays a some of different values. There are four different values here, Ohio, New York, California, and Illinois, and that's going to be submitted. I'll click on it, and click Update. Now we see our Chart and it actually looks pretty much like we expected it to. There are six households, three of them in California, so we see it as half of the Chart. I'll click Save to be sure we keep that. The Google Chart API really is the fastest way to get Charts on your site, but it is somewhat limited. I'm hopeful that the Charts Module will continue to mature to support more and more of the Google Chart API leading to increased possibilities for Charts on your Drupal site.
Get unlimited access to all courses for just $25/month.Become a member