When using event driven programming, it consists of using objects,listeners and handlers.
For example, when creating a game using event drivenprogramming, you use objects such as shapes to be able to interact with yourgame, such as an arrow key taking you to a next level. In order for it toproceed to the next frame or so, you would have to create a listener so thatonce it is clicked it will proceed to the next frame, and once you have clickedit, the listener will call on the handler to carry out this event.Windows 7 is an operating system that allows a user to run programs, savedelete and organise files, as well as using it for other uses such as gaming orlistening to music.
Windows 7 can act as an event driven program as it alsogoes through the same processes when carrying out tasks made by a user. Forexample if a user were to open up a document they would have to go through theprocess of clicking the object, having windows 7 being the listener, it wouldthen have to handle it and carry out the event.You can be able to use Windows 7 to:· Double click to run programs· Keyboard shortcuts· Start menu · Right-click to access propertiesIf a user were to run a program, such as by double clickingit in order for the program to load up, as you are double clicking the icon (onthe desktop), to open it the icon would act as an object, and in this case thebutton, and once double clicked by the user Windows would act as the listener,processing the fact that the item has been clicked and that the user wants toopen it and to start running that program, therefore Windows will then use thelistener to call upon the handler so that it can handle the action and carryout the event, resulting in the program opening and running.
The samegoes for the Start Menu. When you click on the icon it opens up a list of functionsand buttons that can be used and ran by the user, opening up things likeDocuments, Pictures or Applications. For the user to carry out the event ofclicking the start menu to open it up it triggers the mouse click event, whenthe user clicks on the start button (which would be the object), EDP can beused in this process as in order for the list of programs to appear an action isdone, the mouse click (left-click on the object – the start menu) which islistened to by Windows, calling the handler to carry out the event and open upthe start menu as the user wishes to do so.
This is called a Mouse click event.You can useWindows 7 to carry out keyboard shortcuts such as:· CTRL+ESC– open Start Menu· ALT+TAB – Switching from different Tabs open· ALT+CTRL+DELWhen thekeyboard is pressed, event driven programming will process this as KeyDown, KeyUP,and if on the arrow keys, left and right. The object in this keyboard eventwould be the actual keyboard keys pressed. If a user were to use a keyboardshortcut such as ALT+CTRL+DEL, once these keys are pressed Windows would listento this as they are being pressed, and will call the handler so that thehandler can carry out this event. Once it has been handles it will output ontothe screen resulting in the keystroke opening up Windows 7 security, allowingusers to either lock their system, open the task manager, log off, change theirsystems password or switch user, or even putting their system to sleep.
This iscalled a keyboard event.