Flex - Printing Support

Flex provides a special class FlexPrintJob to print flex objects.

• FlexPrintJob can be used to print one or more Flex objects, such as a Form or VBox container.

• FlexPrintJob prints the object and all objects that it contains.

• The objects can be all or part of the displayed interface.

• The objects can be components that format data specifically for printing.

• The FlexPrintJob class lets you scale the output to fit the page.

• The FlexPrintJob class automatically uses multiple pages to print an object that does not fit on a single page.

• The FlexPrintJob class causes the operating system to display a Print dialog box. You cannot print without some user action.

Prepare and send a print job

You print output by preparing and sending a print job. Let's create an instance of the FlexPrintJob class

var printJob:FlexPrintJob = new FlexPrintJob();

Start the print job

printJob.start(); 

Flex will cause the operating system to display a Print dialog box. Add one or more objects to the print job and specify how to scale them

printJob.addObject(myObject, FlexPrintJobScaleType.MATCH_WIDTH); 

Each object starts on a new page. Send the print job to the printer

printJob.send(); 

Printing Example

Following is the content of the modified mxml file src/com.howcodex/HelloWorld.mxml.

<?xml version = "1.0" encoding = "utf-8"?>
<s:Application xmlns:fx = "http://ns.adobe.com/mxml/2009" 
   xmlns:s = "library://ns.adobe.com/flex/spark" 
   xmlns:mx = "library://ns.adobe.com/flex/mx"
   width = "100%" height = "100%"
   minWidth = "500" minHeight = "500" 
   initialize = "application_initializeHandler(event)">
   
   <fx:Style source = "/com/howcodex/client/Style.css" />
   <fx:Script>
     <![CDATA[
         import mx.controls.Alert;
         import mx.events.FlexEvent;
         import mx.printing.FlexPrintJob;
         import mx.printing.FlexPrintJobScaleType;
         
         protected function btnClickMe_clickHandler(event:MouseEvent):void {
            
            // Create an instance of the FlexPrintJob class.
            var printJob:FlexPrintJob = new FlexPrintJob();
         
            // Start the print job.
            if (printJob.start() != true) return;

            // Add the object to print. Do not scale it.
            printJob.addObject(myDataGrid, FlexPrintJobScaleType.NONE);

            // Send the job to the printer.
            printJob.send();
        }

        protected function application_initializeHandler(event:FlexEvent):void {
            lblHeader.text = "My Hello World Application";				
        }
     ]]>
   </fx:Script>
   
   <s:BorderContainer width = "500" height = "500" id = "mainContainer" 
      styleName = "container">
      <s:VGroup width = "100%" height = "100%" gap = "50"
         horizontalAlign = "center" 
         verticalAlign = "middle">
         <s:Label id = "lblHeader" fontSize = "40" color = "0x777777" 
            styleName = "heading" />
         
         <mx:DataGrid id = "myDataGrid" width = "300">
            <mx:dataProvider>
               <fx:Object Product = "Flex" Code = "1000" />
               <fx:Object Product = "GWT" Code = "2000" />
               <fx:Object Product = "JAVA" Code = "3000" />
               <fx:Object Product = "JUnit" Code = "4000" />
            </mx:dataProvider>
         </mx:DataGrid>
         
         <s:Button label = "Print Me!" id = "btnClickMe" 
            click = "btnClickMe_clickHandler(event)" 
            styleName = "button" />
      </s:VGroup>	
   </s:BorderContainer>	
</s:Application>

Once you are ready with all the changes done, let us compile and run the application in normal mode as we did in Flex - Create Application chapter. If everything is fine with your application, it will produce the following result: [ Try it online ]

Click on print me button and you can see the printout of the data grid shown below.