The Space For App Developers

<?xml version="1.0" encoding="utf-8"?>
<s:WindowedApplication xmlns:fx="http://ns.adobe.com/mxml/2009" 
					   xmlns:s="library://ns.adobe.com/flex/spark" 
					   xmlns:mx="library://ns.adobe.com/flex/mx"
					   xmlns:helpers="com.riaspace.helpers.*"
					   preinitialize="windowedApplication_preinitializeHandler(event)"
					   creationComplete="windowedApplication_creationCompleteHandler(event)">
 
	<fx:Script>
		<![CDATA[
			import mx.collections.errors.ItemPendingError;
			import mx.events.FlexEvent;
 
			protected var conn:SQLConnection;
 
			protected const PAGE_SIZE:int = 50;
 
			protected function windowedApplication_preinitializeHandler(event:FlexEvent):void
			{
				// Creating inmemory database
				conn = new SQLConnection;
				conn.open();
 
				// Creating data_tab table
				var createStmt:SQLStatement = new SQLStatement;
				createStmt.sqlConnection = conn;
				createStmt.text = "CREATE TABLE data_tab (value_col TEXT)";
				createStmt.execute();
 
				// Inserting 1000 records to the table
				var insertStmt:SQLStatement = new SQLStatement;
				insertStmt.sqlConnection = conn;
				insertStmt.text = "INSERT INTO data_tab VALUES (?)";
 
				for (var i:int = 1; i <= 1000; i++)
				{
					insertStmt.clearParameters();
					insertStmt.parameters[0] = "value " + i;
					insertStmt.execute();
				}
			}
 
			protected function windowedApplication_creationCompleteHandler(event:FlexEvent):void
			{
				// STEP 1 - query rows count
				var stmt:SQLStatement = new SQLStatement;
				stmt.sqlConnection = conn;
				stmt.text = "SELECT count(*) as rowsCount FROM data_tab";
				stmt.execute();
 
				var result:SQLResult = stmt.getResult();
 
				// STEP 2 - set PagedArrayList.length equal queried rows count 
				pagedArrayList.length = result.data[0].rowsCount;
 
				// STEP 3 - fetch actual data starting from 0 offset (1st row)
				fetchRows(0);
			}
 
			protected function fetchRows(offset:int):void
			{
				// Fetch data rows with specified limit which is our requested page size
				// and offset passed as parameter
				var stmt:SQLStatement = new SQLStatement;
				stmt.sqlConnection = conn;
				stmt.text = "SELECT * FROM data_tab LIMIT :limit OFFSET :offset";
				stmt.parameters[":limit"] = PAGE_SIZE;
				stmt.parameters[":offset"] = offset;
				stmt.execute();
 
				var result:SQLResult = stmt.getResult();
				if (result && result.data)
				{
					for(var i:int = 0; i < result.data.length; i++)
					{
						// Setting return row at offset + i position
						pagedArrayList.setItemAt(result.data[i], offset + i);
					}
				}
			}
 
			private function createPendingItemFunctionHandler(index:int, ipe:ItemPendingError):Object
			{
				// In case synchronous database mode is used fetchRows function should be called
				// after return from this function. With asynchronous mode fetchRows function can
				// be called directly.
				callLater(fetchRows, [index]);
 
				// Returning a message to display
				return "List items are being fetched from database...";
			}
 
			protected function pagedArrayList_initializeHandler(event:FlexEvent):void
			{
				// NOTICE: this is a workaround for a Flex bug that causes invalidIndex error
				// in LinearLayoutVector. It all works well when asyncListView.list property
				// is set after pagedArrayList is initialized and its length property is set.
				asyncListView.list = pagedArrayList;
			}
 
		]]>
	</fx:Script>
 
	<fx:Declarations>
		<helpers:PagedArrayList id="pagedArrayList" initialize="pagedArrayList_initializeHandler(event)" />
	</fx:Declarations>
 
	<s:List width="100%" height="100%" labelField="value_col">
		<s:AsyncListView id="asyncListView" createPendingItemFunction="createPendingItemFunctionHandler" />
	</s:List>
 
</s:WindowedApplication>

	// Wrapping each user into ObjectProxy with selected additional property selected 
	var userProxy:ObjectProxy = new ObjectProxy({user:user, selected:false});
	// Registering event PROPERTY_CHANGE handle
	userProxy.addEventListener(PropertyChangeEvent.PROPERTY_CHANGE, 
		userProxy_propertyChangeHandler);

<?xml version="1.0" encoding="utf-8"?>
<s:WindowedApplication xmlns:fx="http://ns.adobe.com/mxml/2009" 
					   xmlns:s="library://ns.adobe.com/flex/spark" 
					   xmlns:mx="library://ns.adobe.com/flex/mx"
					   xmlns:updater="http://updater.riaspace.com/">
 
	<fx:Script>
		<![CDATA[
			import air.update.events.DownloadErrorEvent;
			import air.update.events.StatusUpdateEvent;
			import air.update.events.UpdateEvent;
 
			import mx.controls.Alert;
 
			[Bindable]
			protected var downlaoding:Boolean = false;
 
			protected function isNewerFunction(currentVersion:String, updateVersion:String):Boolean
			{
				// Example of custom isNewerFunction function, it can be omitted if one doesn't want
				// to implement it's own version comparison logic. Be default it does simple string
				// comparison.
				return true;
			}
 
			protected function updater_errorHandler(event:ErrorEvent):void
			{
				Alert.show(event.text);
			}
 
			protected function btnCheckNow_clickHandler(event:MouseEvent):void
			{
				// First initialize NativeApplicationUpdater
				updater.initialize();
			}
 
			protected function updater_initializedHandler(event:UpdateEvent):void
			{
				// When NativeApplicationUpdater is initialized you can call checkNow function
				updater.checkNow();
			}
 
			protected function updater_updateStatusHandler(event:StatusUpdateEvent):void
			{
				if (event.available)
				{
					// In case update is available prevent default behavior of checkNow() function 
					// and switch to the view that gives the user ability to decide if he wants to
					// install new version of the application.
					event.preventDefault();
					currentState = "updaterView";
				}
				else
				{
					Alert.show("Your application is up to date!");
				}
			}
 
			protected function btnYes_clickHandler(event:MouseEvent):void
			{
 
				// In case user wants to download and install update display download progress bar
				// and invoke downloadUpdate() function.
				downlaoding = true;
				updater.addEventListener(DownloadErrorEvent.DOWNLOAD_ERROR, updater_downloadErrorHandler);
				updater.addEventListener(UpdateEvent.DOWNLOAD_COMPLETE, updater_downloadCompleteHandler);
				updater.downloadUpdate();
			}
 
			protected function btnNo_clickHandler(event:MouseEvent):void
			{
				currentState = "mainView";
			}
 
			private function updater_downloadCompleteHandler(event:UpdateEvent):void
			{
				// When update is downloaded install it.
				updater.installUpdate();
			}
 
			private function updater_downloadErrorHandler(event:DownloadErrorEvent):void
			{
				Alert.show("Error downloading update file, try again later.");
			}
 
		]]>
	</fx:Script>
 
	<s:states>
		<s:State name="mainView"/>
		<s:State name="updaterView"/>
	</s:states>
 
	<fx:Declarations>
		<updater:NativeApplicationUpdater id="updater" 
					updateURL="http://riaspace.com/native-application-updater/update-1.1.xml" 
					isNewerVersionFunction="{isNewerFunction}"
 
					initialized="updater_initializedHandler(event)"
					updateStatus="updater_updateStatusHandler(event)"
 
					error="updater_errorHandler(event)"
					downloadError="updater_errorHandler(event)"
					updateError="updater_errorHandler(event)"
					/>
	</fx:Declarations>
 
	<s:Button id="btnCheckNow" label="Check for updates" includeIn="mainView" 
			  horizontalCenter="0" verticalCenter="0" 
			  click="btnCheckNow_clickHandler(event)"/>
 
	<s:HGroup verticalCenter="0" includeIn="updaterView" horizontalCenter="0" verticalAlign="top">
		<s:BitmapImage source="@Embed(source='/assets/icon128.png')" />
		<s:VGroup width="100%" horizontalAlign="center">
			<s:Label text="New version ({updater.updateVersion}) is available." />
			<s:Label text="Do you want to download it and install?" />
			<mx:ProgressBar id="prgBar" source="{updater}" label="Downloading %3%" visible="{downlaoding}" />
			<s:HGroup>
				<s:Button id="btnYes" label="Yes" click="btnYes_clickHandler(event)" />
				<s:Button id="btnNo" label="No" click="btnNo_clickHandler(event)" />
			</s:HGroup>
		</s:VGroup>
	</s:HGroup>
 
</s:WindowedApplication>