User manual MACROMEDIA FLASH REMOTING MX-USING FLASH REMOTING FOR FLASH MX 2004 ACTIONSCRIPT 2.0

[. . . ] Using Flash Remoting for Flash MX 2004 ActionScript 2. 0 Trademarks Add Life to the Web, Afterburner, Aftershock, Andromedia, Allaire, Animation PowerPack, Aria, Attain, Authorware, Authorware Star, Backstage, Bright Tiger, Clustercats, ColdFusion, Contribute, Design In Motion, Director, Dream Templates, Dreamweaver, Drumbeat 2000, EDJE, EJIPT, Extreme 3D, Fireworks, Flash, Flash Lite, Flex, Fontographer, FreeHand, Generator, HomeSite, JFusion, JRun, Kawa, Know Your Site, Knowledge Objects, Knowledge Stream, Knowledge Track, LikeMinds, Lingo, Live Effects, MacRecorder Logo and Design, Macromedia, Macromedia Action!, Macromedia Breeze, Macromedia Flash, Macromedia M Logo and Design, Macromedia Spectra, Macromedia xRes Logo and Design, MacroModel, Made with Macromedia, Made with Macromedia Logo and Design, MAGIC Logo and Design, Mediamaker, Movie Critic, Open Sesame!, Roundtrip, Roundtrip HTML, Shockwave, Sitespring, SoundEdit, Titlemaker, UltraDev, Web Design 101, what the web can be, and Xtra are either registered trademarks or trademarks of Macromedia, Inc. and may be registered in the United States or in other jurisdictions including internationally. Other product names, logos, designs, titles, words, or phrases mentioned within this publication may be trademarks, service marks, or trade names of Macromedia, Inc. or other entities and may be registered in certain jurisdictions including internationally. [. . . ] · The mySelectionFunction() function takes a record and a letter and returns the value true if the first letter of the record matches the specified letter. · The myRecordSet. filter() method filters the myRecordSet object using the mySelectionFunction() function to create a new RecordSet object. Only those records for which the mySelectionFunction() function returns true are included in the new RecordSet object. · The Contact_grid component's dataProvider property receives a filtered copy of myRecordSet object, generated by the myRecordset. filter() method, as the data for the contact_grid ListBox. Note: For RecordSet objects that have 2, 000 or fewer records, the filter() method generally takes less than one second to finish. The length of time to filter RecordSet objects increases rapidly as the number of records grows. Delivering RecordSet data to Flash applications in ColdFusion MX By default, Flash Remoting returns a RecordSet object to the Flash client in a single response when the application server finishes retrieving the data. In ColdFusion MX, if you expect to return a large record set and the available data transmission speeds are slow, such as when using dial-up modem, you can choose to return a record set from the application server in increments. When you use pageable record sets, the following events occur: · On the server, the record set is held in session data, and server-side Flash Remoting RecordSet service provides access to the records. · On the client, the RecordSet object can download records when needed by the Flash application. About working with RecordSet objects 81 Flash Remoting can deliver pageable record set data to your application in three modes, as described in the following table: Data delivery modes ondemand (default) page Description When you access a particular record using the getItemAt() method, the RecordSet object requests the record from the server-side Flash Remoting RecordSet service. When you use the getItemAt() method to access a record, the RecordSet object fetches data one or more pages at a time. You specify the number of records per page when you set the delivery mode. You can also tell Flash Remoting to get, or prefetch, a number of pages of data that follow the page that contains the requested data. Flash Remoting stores these additional pages in the client if it has not already fetched them in a previous request. The default prefetch value is 0 (only get the page with the requested data). For example, if you specify a page size of 15 records and a number of pages to prefetch of 3, Flash Remoting automatically fetches 45 records when you make your first request for a record in the data set. If you then request a record on the second page that was returned, Flash Remoting prefetches an additional 15 records. As a background activity, the RecordSet object fetches the entire contents of the record set from the server, starting when the service function that retrieves the record set on the application server returns. You can specify a page size when you set the delivery mode to fetchall. Flash Remoting continues requesting one page at a time from the server until all pages have been returned. The default page size is 25 records. fetchall You change a RecordSet object's delivery mode by calling the setDeliveryMode() method, as in the following example: function getCustomerData_Result( dataEvent:mx. rpc. ResultEvent ):Void { if (config_panel. deliveryMode. getData() == "page") { theRecordSet. setDeliveryMode("page", contact_grid. getRowCount(), 1); } else if (config_panel. deliveryMode. getData() == "fetchAll") { theRecordSet. setDeliveryMode("fetchAll", 10); } else { theRecordSet. setDeliveryMode("onDemand"); } } In this example, theRecordSet object represents the record set returned from Flash Remoting, and the config_panel object represents a Flash movie clip. Using the deliveryMode. getData() method, the code evaluates the delivery mode specified by config_panel, and uses the setDeliveryMode() method to set the mode of delivery for the RecordSet object. 82 Chapter 4: Using Flash Remoting Data in ActionScript If the config_panel object specifies page mode, the setDeliveryMode() method tells Flash Remoting to set the page size to the number of rows in the contact_grid movie clip and to prefetch one additional page beyond the page with the requested data, if it is not in memory. If the config_panel object specifies fetchall mode, the setDeliveryMode() method tells Flash Remoting to set the page size to 10 records and start getting the records, one page at a time (if they are not already on the client), until the entire record set has been fetched. For all delivery modes, after a record is received from the application server, it is held inside the RecordSet object. Any getItemAt calls for records that the client has not yet received fetch the requested record as soon as possible and return a fetch pending message. Using Flash UI components with RecordSet objects Many Flash UI components can use RecordSet objects to provide both label and data information. These components use Flash DataProvider objects to supply the following information: · Label values that appear to the user · Corresponding data values that are available by using the component's getValue() method after the user selects a label Objects that can use DataProvider objects are often referred to as data consumers. [. . . ] In some cases, you might be able to include recovery code, such as code to retry a call to a busy server, in the error handler. Handling errors for a Connection object 169 The error object When Flash Remoting receives a status event, Flash passes an error object that contains information about the error to the status event handler. The error object has the following format: Key name code level description details type rootcause Contents Currently, always SERVER. PROCESSING. A stack trace that indicates the processing state at the time of the exception. A nested error object that contains additional information on the cause of the error. [. . . ]