Key Features of event driven programming

Task 1: explain the key features of event driven programs

When using event driven programming it is first important to understand the advantages and key features of the programming type these advantages include service oriented, time driven, event  handlers, trigger functions, events including use of mouse, keyboard HTML object, form, user interface, programming loops, flexibility, suitability for graphical interfaces, the simplicity of the programming and the ease of development which event driven programming provides.

Service Oriented: service oriented programmes are programmes that often appear in the background and have no user interface to use but all have the ability to be stopped and started at the users will. These programmes can also be set to activate immediately when your pc starts up. Examples of these sort of programmes are Bluetooth, Autodesk functions, NVidia display driver and other programmes that offer customizable features that are not necessarily essential for your computer to have. Also because these programmes are constantly using your memory for background programmes which may be non crucial to the running/ maintaining of your pc it can be seen by many as a waste of memory for some of the functions being run.

Time Driven: Time Driven programmes such as antivirus scans, task scheduler and operating system updates are important features in the maintain and running of your pc. These events follow real time settings and variables in there programming generally used to plan out maintence and update tasks that occur on future dates and at future times. Because of this time settings they can be planned to take place at regular intervals that does not have to be independently monitored by the user and will not be interrupted by other programmes and processes taking place while the timer to begin this is important when it comes to safety critical operations such as antivirus scans and updates.

Event Handlers:

Event handlers within programming are sections of code that are set out to denote the actions of event triggers within the coding structure e.g. the effect it will have on the programme if I right or left click can have different results if programmed differently leading to a secondary programming step of the code giving an alternate outcome. The image above shows an example of sub procedure created in visual basic that utilizes the trigger of closebutton_click which means that a button within the programme will close when the user triggers it by clicking. 

Trigger functions: trigger functions are used to be able to designate a specific coded event with an action e.g. click the button to trigger the calculation on a calculator which works out the result based on your input numbers until the event is triggered. The trigger functions are a big part of the appeal of object oriented programming because it gives the user a lot of flexibility in the way that they are able to trigger events within there programmes.

Events: events can be sub categorized into five different categories which refers to different hardware and software uses of events. These events are: mouse events, keyboard events, HTML object events, Form events and User Interface Events.

Mouse events: mouse events refer to actions performed by the mouse which can be dependant on either mouse buttons e.g. left click, right click, double click; the scroll wheel e.g. scroll up, scroll down, scroll wheel click or even mouse motion and movement sensor e.g. mouse move forward, back, left, right.

Keyboard Events: Keyboard events refer to actions performed with a keyboard which is dependant on either individual key presses of any keys on the board or even a combination a good example of this is Ctrl+Alt+Delete function which triggers a windows menu which allows you to lock your computer; change your password or open your task manager using a windows operating system.

Html Events: Html events such as onclick, onmousemove and onkeydown is used in online applications using software like JavaScript and cascading style sheets which are designed for working on browser applications. These triggers are not to be confused with hardware mouse and keyboard events despite being similar these events are only for use on web browsers. 

 

Forms: forms are used to contain controls and options such as textboxes, checkboxes and list boxes a prime example of these is the font window within Microsoft word. Forms act as control windows containing options and features which provides a rich user interface when using applications.

 

Event loops: event loops constantly monitor the events in the program continuously relooping looking to see if an event has been triggered and if an event handler exists to execute these events then they are executed within the application.

 

 

 

 

 

User interface events: user interface events are one of the key features of event driven programming because most applications that are created using event driven programming e.g. calculators apps use buttons as a graphical representation of the number. these buttons are required to trigger the event to begin inputting the sum to create a calculation. 

 

Flexibility:  one of event driven programming's greatest advantages is its flexibility and the range of applications that can be created to suit different functions and  also that the programmer has a greater use of events available which gives the programmer a greater amount of control over how the program should respond to specific triggers and as a result of those triggers what events should take place.

 

Suitability for graphical interfaces: event driven programming is very suitable for graphic interfaces due to the range of event commands that are available which prove very compatible with graphic interfaces e.g. mouseover, keystroke, click or touch event the suitability of these events when using graphical buttons labels or textboxes is very effective.

 

Simplicity of programming: event driven programming languages can make programming very simple compared to traditional flow driven languages because of the very visually based programming style. This method of programming makes it easier because they show the programmer a choice of event commands that are possible to use for that section of code and allow the programmer to choose an appropriate command without actually typing it making the coding process both faster and more accurate.

 

Ease of development: program development can be easy with an event driven language, as the programmer only needs to work on one event control at a time. Flow driven languages need to be reasonably complete before they can be run and tested, whereas an event driven language will run with as little as only the code for a single event completed. Testing is also easier because each event can be tested in turn.

 

Advantages of event driven programming: The key advantages of event driven programming are that they are primarily designed for the creation of programmes that incorporate user interactivity e.g. graphical user interface programmes utilize some form of event driven programming an example of this is how video games story events are triggered by an action the player takes to allow the game to progress forward via the use of event driven programming e.g. flicking a light switch allows you to see the exit of a dark room allowing you to continue. Another advantage of event driven programming is that it allows for sensors and other hardware types to easily interact with software an example of this would be the interactivity between the use of a tablet computer and the software that is available to it. via the use of touch screen technology the sensors on the pad are designed to detected the use of touch and hand gestures to help interact with the software on the tablet.

 

The main features and benefits of visual basic: The main features and benefits of Visual Basic is that firstly the software itself is free source meaning that its available to everyone. Secondly the software is constantly supported and new iterations of the program are released with newer features and often better user accessibility meaning that it becomes easier for newer programmers and is widely available. a third advantage of visual basic is that it is widely known for its rapid application development cycle and is often preferred by software developers for more the creation of more basic applications than any other software available.

The main features and benefits of visual basic for applications: The main features and benefits of Visual Basic for applications is that while being very similar to visual basics only the program itself is embedded into another Microsoft application such as excel or access. by using this program it allows the user to create macros or smaller programmes within a Microsoft application e.g. if you wanted to create a print macro button that when pressed would print to a specific specification unlike going through the main print options menu.

The main features and benefits of ColdFusion: The main benefits of using the ColdFusion programming language is that when developing an online application compared to java a java application ColdFusion requires a lot less coding meaning that programmes can be completed in a much shorter duration of time. this however does market this programming language to newer programmers who maybe unfamiliar with the java programing language while experienced java programmers may find this to basic for the sort of programmes they require to create larger programmes.

The main features of Integrated Development software: an IDE or integrated development environment is a programming environment built into software applications that provides the user with all the essential tools which are used for the creation of an application. the tools provided include a GUI builder, a text or code editor, a compiler and a debugger. two of the most common types of IDE's are Visual Basic and Dreamweaver.