Explains how to use asynchronous requests.
SingleRequest: asynchronous programming without active objects
RealLifeWaitLoop: asynchronous programming without active objects
AcceptInput1-2: asynchronous programming with active objects
AcceptPrintInput: asynchronous programming with active objects
Download
Click on the following link to download the example: SingleRequest.zip
Click on the following link to download additional file: CommonFramework.zip
Click browse SingleRequest to view the example code.
Click browse CommonFramework to view the additional file.
Click on the below link for Example which demonstrates Asynchronous requests ClientServerAsync .zip .
Browse the S60 files. ClientServerAsync .
Description
This example shows how to issue and wait for a single request.
The example shows the general principles involved in asynchronous programming. It uses a simple wait loop and shows how the completion of asynchronous events are handled without active objects.
This example does not use active objects deliberately.
Class summary
Security issues
The example requires no specific capabilities in order to run - and does not demonstrate any security issues.
Download
Click on the following link to download the example: Waitloop.zip
Click on the following link to download additional file: CommonFramework.zip
Click browse Waitloop to view the example code.
Click browse CommonFramework to view the additional file.
Description
This example shows how a wait loop can be used to identify and handle a completed request.
It shows the general principles involved in asynchronous programming. It uses a simple wait loop and shows how the completion of asynchronous events are handled without active objects.
This example does not use active objects deliberately.
Class summary
Security issues
The example requires no specific capabilities in order to run - and does not demonstrate any security issues.
Download
Click on the following link to download the example: RealLifeWaitLoop.zip
Click on the following link to download additional files: CommonFramework.zip
Click browse RealLifeWaitLoop to view example code.
Click browse CommonFramework to view the additional file.
Description
As with the WaitLoop example, this example shows how a wait loop can be used to identify and handle a completed request. However, this example shows how the wait loop can deal with multiple asynchronous service providers.
The example shows the general principles involved in asynchronous programming; it uses a simple wait loop and shows how the completion of asynchronous events are handled without active objects.
This example deliberately does not use active objects.
Class summary
Security issues
The example requires no specific capabilities in order to run - and does not demonstrate any security issues.
Download
Click on the following link to download the example: RunComplete.zip
Click on the following link to download additional files: CommonFramework.zip
Click browse RunComplete to view the example code.
Click browse CommonFramework to view the additional file.
Description
The example shows how active objects and an active scheduler can be used to handle asynchronous events. Compare this with the following examples; SingleRequest, WaitLoop and RealLifeWaitLoop.
It demonstrates a single CMessageTimer active object which runs until completion.
Class summary
TRequestStatus CActiveScheduler CActive CTimer
Security issues
The example requires no specific capabilities in order to run - and does not demonstrate any security issues.
Download
Click on the following links to download the examples:
Click on the following link to download additional files: CommonFramework.zip
Click on the following links to view the examples:
Click browse CommonFramework to view the additional file.
Description
These examples show how active objects and an active scheduler can be used to handle asynchronous events.
They demonstrate a single CKeyMessengerProcessor active object (derived from class CActiveConsole), which accepts input from keyboard, but does not print it. This
object contains a CMessageTimer object which it activates
if the user inputs the character "m" and cancelled if the user inputs
"c".
Class summary
TRequestStatus CActiveScheduler CActive CTimer
Security issues
The example requires no specific capabilities in order to run - and does not demonstrate any security issues.
Download
Click on the following link to download the example: AcceptPrintInput.zip
Click on the following link to download additional files: CommonFramework.zip
View the source code browse AcceptPrintInput. View the additional file: browse CommonFramework.
Description
This example demonstrates how to accept and print keyboard input to a console using active objects.
The example implements
a class called CWriteKeyProcessor which is an active
object that requests and handles keyboard input in its ProcessKeyPress() method. An alphabetic or space character is printed as a character,
anything else is printed as an integer. Pressing the escape key terminates
the application.
Class summary
CActiveScheduler CActive CTimer
Security issues
The example requires no specific capabilities in order to run - and does not demonstrate any security issues.
Download
Click on the following links to download the examples: Fibonacii1.zip
Click browse Fibonacii1
Description
These examples show how active objects and an active scheduler can be used to handle asynchronous events and long-running services to maintain system responsiveness.
Class summary
TRequestStatus CActiveScheduler CActive CTimer
Security issues
The example requires no specific capabilities in order to run - and does not demonstrate any security issues.