riaxe snippets
Posts tagged AIR
Pagination in Flex
Jun 9th
Recently while working on a flex project, had an issue while paginating a list of data. Could find many solutions for paginating of Datagrid and lists on the web but I needed little different. So created an application to paginate a large amount of data. This isn’t using any Datagrid or List but a simple VBox. I added some effects as well to it. I used a canvas having a list of images and at the bottom the paginator is placed with the “First”(<<), ”Previous”(<), “Next”(>) and “Last”(>>) buttons for navigation. One can click on the page number to navigate to any specified page.
We need 4 properties to set on application loading complete.
1. Set selectedIndex = 0 ; // As we need to show the first page on load complete.
2. Set visiblePages = the number of pages we want to show every time. Here the visiblePages = 3.
3. Set totalItems = the total number of items
4. Set itemsPerpage = the number of items to be shown in a page.
Screenshot given below.
You can click here to see the example.
I think this sample could be useful for all. Do post back for any issues or suggestions.
Thanks.
Simple tutorial for creating an AIR application using Merapi Bridge
Mar 15th
Googling around the web I found the Merapi AIR-Java Bridge really interesting. I created a screen capture application using the AIR window to capture screenshots of the windows desktop through Java [http://www.youtube.com/watch?v=Gp2BzQi-gSU]. Thought of creating a simple tutorial or example of how it works.
Java
- Create a new Java project named MerapiExample
- Add the Merapi jar files into the library [flex-messaging-common.jar, flex-messaging-core.jar, merapi-0.0.80.jar, tools.jar].
- Create a package inside the src folder named merapi.java
Create a class named SimpleMerapi.java which implements ImessageHandler as shown below:
package merapi.java;
import merapi.Bridge;
import merapi.messages.IMessage;
import merapi.messages.IMessageHandler;
import merapi.messages.Message;
public class SimpleMerapi implements IMessageHandler {
public void handleMessage(IMessage message)
{
try
{
merapi.messages.Message msg = (merapi.messages.Message)message;
System.out.println( "Received \"" + msg.getData() + "\" from Merapi Flex" );
System.out.println( "Responding with \"Hello Merapi Flex\"\n" );
// Instantiate a Message to respond to Merapi Flex
Message response = new Message( "simpleMerapiType", "Hello Merapi Flex" );
// Send message to Merapi Flex
Bridge.getInstance().sendMessage( response );
}
catch(Exception exception)
{
exception.printStackTrace();
}
}
/**
* main method that instantiates the Bridge...
*/
public static void main(String[] args) {
System.out.println( "Merapi Started\n" );
// Register MerapiHelloWorld as a listener for messages of type "helloWorldType"
Bridge.getInstance().registerMessageHandler( "simpleMerapiType", new SimpleMerapi() );
}
}
AIR
- Create a new AIR project named MerapiAIR
- Add the merapi-core.swc into the library
- Create a button control and a VBox containing a Label and a Text control as shown below:
<?xml version="1.0" encoding="utf-8"?>
<mx:WindowedApplication
xmlns:mx="http://www.adobe.com/2006/mxml"
xmlns:merapi="merapi.*"
layout="vertical" verticalAlign="top" horizontalAlign="center">
<merapi:BridgeInstance id="bridge" result="{responseText.text += bridge.lastMessage.data.toString()+'\n';}" />
<mx:Script>
<![CDATA[
import merapi.messages.Message;
private function onClick():void
{
bridge.sendMessage(new Message('simpleMerapiType', 'Hello from Flex!!'))
}
]]>
</mx:Script>
<mx:Button id="sayHelloButton"
label="Click to Say Hello to Merapi Java"
click="onClick()" />
<mx:VBox horizontalAlign="center">
<mx:Label text="Reponse from Merapi Java:" />
<mx:Text id="responseText" />
</mx:VBox>
</mx:WindowedApplication>
- Now run the Java app first and then run the AIR app to the example in action.
- It is not possible to start the Java app from AIR. So we can start the AIR app directly from Java using this Runtime.getRuntime().exec(“AIR app installtion path”); This way the AIR app will run directly from the Java app.
Note: This example was taken from the Merapi forum HelloWorld example.
Hope you enjoy it 
Adding namespaces in Actionscript3.0
Jan 26th
By defination – Namespaces give you control over the visibility of the properties and methods that you create. Think of the public, private, protected, and internal
access control specifiers as built-in namespaces. If these predefined access control specifiers do not suit your needs, you can create your own namespaces.
We can create our own namespaces in Actionscript 3.0.
Suppose we have a class named Employee having a method within named calculateSalary();
We can create our own namespaces to see the difference in incentives for RIA developers. We will create two namespaces as follows:
package com.xyzsystems.namespace {
public namespace codevils=http://riaxe.com/blog;
}
package com.xyzsystems.namespace {
public namespace others;
}
Lets create our Employee class where we will use these namespaces as follows:
package com.xyzsystems.employee
{
import com.xyzsystems.namespace.*;
public class Employee
{
others static function calculateIncentive():Number{
return 5000;
}
//
codevils static function calculateIncentive():Number{
return 7500;
}
}
}
We are done with the class. Lets test the calculateIncentive() method for different namespaces.
package com.xyzsystems.test
{
import com.xyzsystems.namespace.*;
import com.xyzsystems.employee;
import mx.controls.Alert;
use namespace others;
// use namespace codevils;
public class TestEmployee
{
public function TestEmployee():void {
var incentive:Number = Employee.calculateIncentive();
Alert.show("The incentive for the employee is :"+incentive);
}
}
}
The Alert will show this “The incentive for the employee is : 5000″;
We can also define the namespace like this -
var incentive:Number; incentive = Employee.codevils::calculateIncentive();
This would result in “The incentive for the employee is : 7500” in the Alert.