On June 1st we launched the public beta for Flash Builder 4, the newest iteration of our Eclipse-based IDE for RIAs, formerly known as Flex Builder 3. While you can find both evolutionary and revolutionary features in it, in this article I will touch on the data features and Flex – PHP integration features of Flash Builder 4.
In this article, I will show you how can you use a PHP class that manages a MySQL table (offering CRUD operations) in a Flex project. I will build the Flex project and I rely on Flash Builder 4 to set up the Zend Framework for me(because I want to use remoting as a way to talk with the PHP server). After this I will use the new wizard from Flash Builder 4 that introspects a PHP class and creates the ActionScript code to consume that PHP class.
In the end I should be able to have a simple Flex app that lets me see the data records, edit them, and add a new item. For some of the features I’ll have to write code, for others Flash Builder will generate the code. All in all, I think the application can be created in less than 30 minutes.
I have two PHP classes that I want to reuse with my Flex application. One class is a data object that acts asa wrapper for one row from my database (MySQL). Here is the structure of the table:
id_aut – primary key
The PHP data object, called VOAuthor, looks like this:
The second class, called Authors, is the class that manages the table, offering CRUD operations. The code is very straight forward, I don’t use any database abstraction layer. I have three methods one each for reading, deleting, and updating/inserting a record. I use the data object, VOAuthor, within these methods. This is the code:
These two scripts sit inside of a folder called “remoting” in the root of the Apache web server document root folder.
Creating the Flex project and the UI of the app
I have the PHP files in place; now it’s time to create the Flex application. First, I need to create a new Flex project. Having opened the Flash Builder 4, I use the “New Flex Project” wizard to create a new Flex project called FlexPHPAMF. Make sure that in the wizard you choose PHP as the server technology, and you give the correct information for the document root of the web server (absolute path and URL).
Now let’s create the UI of the application. To do this, I chose to go in design mode where I added two buttons and a data grid to the stage. One button is labeled “Get Data” and the other one “Save Data”.
Using the data service panel
Finally, I am ready to use the new data wizards.At the bottom of Flash Builder, there is a view called “Data/Services”. Click on “Connect to Data/Service” link. A wizard starts, and you can select the type of the data service.
Because I want to use the PHP classes I have, I choose PHP and I click “Next”.
On this page, you can select to either reuse an existing service from the server, or to let the wizard create a stub for you. Because I have the service, I want to use the Import PHP class option. Flash Builder introspects the service in order to detect the supported operations (in this case, because I am using remoting, it detects the public methods and the return type). But to do so, it needs to install the Zend Framework to your web server.
What is very cool is that you don’t have to worry about the steps needed to install Zend Framework. Flash Builder will do it for you automatically.
After the Zend Framework is installed, on the last page of the wizard you’ll see the available methods. Click Finish.
Now, in the Data/Services view you should have a tree, with the root node named Authors. This is the name of the PHP class that you want to use in Flex. Under this node you have Data Types, and the three methods: deleteData(), getData(), saveData().
At the same time if you take a look at the project structure in the Package explorer, you’ll notice that new packages and files were created.
There is a new package called services.authors, and here you’ll find the service class that you’ll use to connect to the PHP class (Authors.as). This class actually extends a base class that implements all the logic using RemoteObject. The reason for this approach is that when you need to do your customization, you’ll do it in the Authors class. If you decide to use Flash Builder to regenerate the code for the same service (maybe as a result of a change on the server side), this operation will not over write your custom code.
The same goes for the data object (or value object). Flash Builder generated the ActionScript value object to match the PHP class VOAuthor. But again, you might want to do some customizations, and you can do it by touching VOAuthor that extends _Super_VOAuthor. All the generated code stays in the _Super_VOAuthor.
And finally, you’ll find a folder called services that gives you quick access to the Authors.php class.
It is time to fill the data grid with the data from the server. To do so, first you need to make sure that the return type for the getData() operation is an array of VOAuthor objects. If you right click on the name of the operation in the Data/Services view and choose Configure Return Type, you have a way to specify the array of VOAuthor:
To bind the data grid to the result of the getData() operation you have to go into design mode, and then drag and drop the getData() (from the Data/Services view) to the data grid.
If you switch to code view, you’ll see that some ActionScript code was added to the flexPHPAMF.mxml. What you want to do is to grab the line from the function and create a new function that will be called when you click the “Get Data” button and paste the code inside of it. My code looks like this:
The wizard altered the data grid itself, you have the name of the table fields as labels, and the data provider of the data grid is set to the lastResult of the getDataResult object (this object was added to your code by the wizard, in order to help you manage the results of the authors service).
If you run the application and press the “Get Data” button, you should see the data.
Adding editing capabilities
The final part of this tutorial is adding the editing capabilities. I want to be able to edit an existing record using the data grid itself, and I want to have a form and a new button. First go back into design mode, drag and drop an new button on the stage, and change the label to “New”. Then, you’ll use another wizard to generate the form for editing. To do so, you select from the Data/Services view the Data Types node, expand it, and select the VOAuthor node. Right click it and select Generate Form. In the wizard choose “Make form editable” and click Next.
In the second page of the wizard deselect the “id_aut” property. This value will be auto-inserted by the database itself. Click Finish.
After the form is generated, you want to grab the form and position it maybe below the buttons. Also, you may want to change the labels. Finally add a new button in the form and label it “Add”.
Switch back to code view. Now, you need to make some changes. First of all (I think it is a bug), the text fields are not editable (they are Text instead of TextInput). So change the type to TextInput to make them editable. Next, give an ID to the Form itself. I want to have the form invisible when the application is loaded, and only make it visible when the users clicks “New”. For that you set the visible property on the form to false, and you add some code to the New button. Here is my code:
And if you look in the code, you’ll notice a new object was created:
You’ll use this instance of the value object VOAuthor to send the new item to the server (remember, the PHP saveData() method expects a single argument of type VOAuthor).
To do so, you need to create a binding between the two text fields from the form and the properties fname_aut and lname_aut of the VOAuthor.
The last missing piece is the actual call to the saveData() method. This is very simple;on the click event of the “Save” button you add the call to the authors object getData() method, passing the local instance of VOAuthor (vOAuthor) as the argument:
You can add a new record now. What about editing an existing one? For this we will need a little bit more code. First, you want to register a listener on the data grid in order to know when something was edited (if you set the property editable to true on the data grid, then you can edit information inline). The event you are looking for is itemEditEnd:
Now,let’s define the listener, dataEdited(). Add the following code in the script section of the page:
This code uses the instance of the value object VOAuthor to store the data used by the edited row.
The last two things you have to do is to create a function called saveData() that is called when the user clicks the “Save Data” button, and to add initialization code for the vOAuthor object when the users clicks the “New” button (this way you avoid updating an item instead of adding a new one if you first edit a row and then add one):
The final code of the MXML file should look like this:
The delete operation is left as homework for you! Basically you want to get the selected row, grab the object data used by that row and save it into vOAuthor, and then call the authors.deleteData(vOAuthor).
If you are not sure what remoting and the Zend Framework are, you can read my post that explains these matters: Flex and PHP: remoting with Zend AMF. This article uses Flex Builder 3 (the previous version of Flash Builder 4).
You might be wondering about many-to-many or one-to-many associations. Well, at least for now there is no support for PHP (at least there is no wizard that handles any association and generates all the code). Still, I think I could do it much easier using these wizards than without them. Having the glue code generated for me and the Value Object created automatically, being able to have a form generated for a particular data model are all great help. You save time, you save money. Remember with any line of code you write, you might introduce a bug or more. Having more lines generated for you means less bugs :).
If you want to take a look at my project, you can download it from here (you’ll find the PHP files and the dump of the database in the service folder from this archive). If you want to install Flash Builder 4, you can grab the beta version from here and use it.
Finally I encourage you to try this for yourself, and let me know what you think. If you find bugs or you want more features in Flash Builder 4, be sure you go to http://bugs.adobe.com and ask your friends to vote for the bug. In the end, this is a beta product. If we can improve it, why not?