unit 14 assignment

Unit 59/75??

Task one:

Web Authoring/ Computer Interfaces

Explain the key features of the event driven programs

(a)Service Oriented Event drive programs provide a service to the user. An email will arrive when the USB is plugged in. This usually works in the background and the user only notices it when it is triggered.

(b) Time Driven This occurs when a computer triggers a particular response or event to happen when a set time is reached. An example of this could be an anti-virus starting at a certain time of the day. The clock that has been set sends a message for the computer to respond in a certain way. Numerous events can happen throughout the day and a list of these is usually kept in a scheduler. An example of this could be a System backup at 6.00 pm every Friday afternoon or an Anti-virus scan at 1.00 am each day. It’s when the control flow of the computer program is driven by a clock and is often used by real time computing. Users to decide to add new events and how frequently to run them/ cancel / skip / delete events.

(c)Event Handler This is the actual code that will be run when the event has been detected. An example is when a button (btnNext) has been clicked. Private void btnNext click(object sender, EventArgs e) { MessageBox.Show(“Button clicked. . . . .”, “Click. . .”); } This will be the code behind the button

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(d)Trigger functions Most event driven programs use trigger functions. These allow the handler to choose which event needs to be run for the event which has occurred. Each and every object has its own set range of trigger functions. Most objects have one trigger function for each possible event that may be likely to occur. The trigger functions have to be defined in order for it to work correctly. If this is not done then there will be no properties or methods for that specific control. For example, after a button has been clicked they tell the system to run private void btnNext Clicked(object sender, EventArgs e) Which is the event handler.

(e) Events When the keyboard button is pressed this action causes the code to be called an event. Events can come from the user or often other sources e.g. timer, computer boot up etc. Examples- On a form : Mouse clicks keyboard press (Up/Down) HTML objects (Submit button, Reset button) These kinds of tools will allow programmers to create GUI (graphical user interface) instead of the command line interface or menu-based interfaces. GUIs are a lot easier to use.

(F)Event loop

The event loop is a programming construct that waits for and dispatches events or messages in a program. This happens when a request is made to some internal or external event provider. This provider generally blocks the request until an event has arrived. Then it calls the relevant event handler. The event-loop may be used together with a reactor. The event provider follows the selected file interface. The event loop almost always operates Data transfer in which signals are sent in spurts, spaced by varying time intervals with the message originator. Frequently the event loop forms the central control flow construct of a program, and then it may be termed the main loop or main event loop. This title is appropriate because such an event loop is at the highest level of control within the program. Ronan Cunningham

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A process whereby the computer is continually checking for events. The computer works in millisecond. 1 second = 1000 milliseconds. The computer will be checking many times each second/ When an event is detected the trigger function is called, which calls the appropriate event handler. Example : When a button is pushed > interrupts the event loop/ The event loop calls the trigger function. The trigger function calls the Event handler. (g)Flexibility A wide variety of programs can be written for many different application e.g. a program for a burglar alarm to an accounting package. Event driven program – provides a very intuitive interface, e.g. people will find it easier to click a button, rather than type in commands such as: load“programName” Run”programName” It is easy to modify the code in an event driven program. The programmer has a wide range of events available which gives them greater control over how the program should respond to specific triggers and as a result of those triggers what the code should do. (h)Suitability for Graphical Interfaces Even driven programming is at the center of GUIs because of the range of event commands that are available which prove they work together well with graphic interfaces e.g. mouse-over, keystroke, click or touch. Event driven programming provides the working aspects to the Graphics user interface. (i.e. the code ‘code behind’ the button or the combo box) with the arrival of touch screens mobile phones/ tablets new events like slide, pinch and swipe have been added, These tools lets the programmers make GUIs based on Windows, icons, menus, pointers (WIMP) rather than an interface based on menu based interfaces.

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(i)Simplicity of Programming Most of the code for the Graphical User Interface or GUI is created automatically when a programmer drags and drops the controls onto the form. The problem is that it can be broken down into events that are to be recognised, so the programmer can focus on making a code for that event handler. Example e.g private void btnCalculate_Click(object sender, EventArgs e) The programmer can double click the button will be placed behind the button. The Integrated Development Environment or IDE automatically the event handler stub. This saves on syntax errors and it can makes coding a lot easier. Individual event handlers can be tested independently. The IDE can provide a intelli sense which will help you avoid syntax errors.

(j) Ease of development Event driven programming can make development a lot easier because the programmer can drag and drop the controls like textbox, button or radio button onto the form. The code can be changed easily. Integrated Development Environment (IDE) (Visual Studio) reduces typing errors and other common mistakes and this intellisense makes it easier to avoid syntax errors. The Properties Window allows the programmer to set and change the properties of objects more simply.

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Task 2 One of the first examples of an event driven program within an operating system is the initial start-up process which is triggered by pressing the power button. The OS is loaded into memory. The OS will handle any kind of user inactivity. Examples include (double) clicking icons, resizing windows etc. in any order the user carries them out this is what makes event driven the best way to develop an Operating System. Some examples include : •

clicking an icon

•

moving an icon

•

dragging a window

•

resizing a window

•

dragging and dropping a selected item

•

clicking on a menu item

•

minimising or maximising a window

The OS will also deal with the effect of user interaction like right-click on the desktop the OS will show a floating menu.

If the user double clicks on a file to open it, the OS will firstly open the application that the file is associated with e.g. myWork.docx open MS Word.

Resizing a window / Minimising / Maximising

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The OS also handles keyboard events, which a lot of them will pass to the running application like word while others are handled the OS itself. E.g. crtl + alt + Del

The operating system recognises hardware events and responds to them. Printer Jam > Inform user USB pen inserted into USB slot

(Autoplay)

Inserting a CD Power Off switch

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Task 3 Air conditioning If the person using the air conditioner turns the dial or presses a button to set it at a temperature. Some air conditioners have seniors can if it gets too hot/cold it will change the temperature automatically.

Smoke Alarm Smoke alarms will warn you that there might be a fire nearby. Smoke alarms have a built in sensor and when there is no smoke detected it will remain off. When smoke is detected the smoke alarm will turn on and warn you with a large rining. If you ever wanted to test the smoke alarm all you need to do is press the smoke alarm and wait for it to ring.

Burglar Alarm Burglar alarms have something called contact switches which send light beams. If a light beams send a signal around the house and it is usually connected to a door or window. If someone opens a door or a window contact will break with that object and a wireless signal will be sent to the central panel and then an alarm will sound to warn the home owners and the security company will be contacted. The owners can be contacted through mobile. The user can enter a code to turn off the alarm.

Bank card

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When the owner of the card enters his card into an ATM (Automated teller machine) it will read the magnetic stripe on the back of the card and then the Arc Num screeb tells the user to enter his/her PIN number. When the User enters their PIN number the system will verify the user and will check that their PIN and their Arc Num match. Then the User can decide how much money to withdraw then pints receipt.

Washing Machine The user puts their clothes into the washing machine and closes the door. They select what washing programme to use. The machine will open a inlet valve to let water in, The machine will let the water in and based on the weighs how much water has entered. When enough water enters the valve closes. The is then heated and a temperature sensor will check to see if the water is hot enough then switches off the heater. The wash programme that the user chose will be activated and it will also display the time on how much time is left.

Elevator When the user presses the button to call the elevator. If the user presses the up button the elevator will stop at his/her floor when going up. When the user press the down button the elevator will stop at his/her floor when going down The elevator will not stop at the users floor while going in the opposite direction the user wants to go. Example: The user wants to go down but the elevator is going up, the elevator won’t stop at the users floor until it starts going down. The only exception is that if nobody is in the elevator or nobody on any other floors has called it. Sometimes there will be a light above the elevators door to show you what floor it is at. When the user picks a floor to go to the elevator will go to that floor and pick up anybody else going in the same direction.

Conclusion Ronan Cunningham

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These events happen in non-graphical applications. Non graphical application systems are systems that don’t have any graphical interface but instead have event driven programs to controls to control them. They are also known as embedded systems like burglar alarms, bank card or air conditioners, etc.

Task 4 C# C# is similar to other programs like C, C++, Java or JavaScript thus it makes switching between languages easier. C# can be used for RAD (Rapid Application Development

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Unit 59/75??


Data Dictionary Variable

Data Type

Form

User for

double

Form1

The total cost of all the food

Main form

+ delivery

Form 1

The cost of delivery

Name totalCost deliveryCharge

double

Main form today

staffArray

DateTime

Array of strings

Form1

Storing the current date and

Main form

time

Form Login

Storing login details (User names)

loginCount

integer

Form Login

The number of attempts to login

PriceHolyrood2oz

double

Form Burger

double

Form Burger

double

Form Burger

double

Form Burger

double

Form Burger

double

Form Burger

PriceHolyrood4oz PriceHolyrood8oz PriceAngus2oz PriceAngus4oz PriceAngua8oz PriceRoyal2oz PriceRoyal4oz PriceRoyal8oz PriceHonest2oz PriceHonest4oz PriceHonest8oz PriceRanch2oz PriceRanch4oz PriceRanch8oz Price2oz Price4oz Price8oz

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Price of the burger chosen

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Login Form

Ask user to enter their username

LoginCount = loginCount + 1

// search the array to find if the username exists For Loop (x = 0; x
If (loginCount == 3) Inform user 3 chances are up Exit EndIf

Order burger Main Form User selects the burger they want A new form appears – frmBurgerDetails

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User selects burger size User selects toppings

2oz, 4oz, 8oz Onions, Ketchup, Bacon, Cheese, Coleslaw

User selects Calculate If (2oz selected) Price = x.xx Else if (4oz selected) Price = x.xx Else if (80z selected) Price = x.xx

// calculate the extras If (onions selected) Price += x.xx If (Ketchup selected) Price += x.xx

Etc.

Price, size of burger, extras – are all passed back to main form. Delivery If user selects delivery Add £3.00 to total

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Method of Payment If user selects PayPal Show website If user selects Credit Card Open CreditCard form

New Order Clear all the commands Print Print the receipt Exit Close the Program

Credit Card Form User enters credit card number 16 digits User enters CVC 3 digits User enters Month CC expires Year CC expires Flexbility A wide variety of programs can be written for many different application e.g. a program for a burglar alarm to an accounting package.

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Event driven programming – provides a very intuitive interface, e.g. people will find will it easier to click a button, rather than type in commands such as: load “programName” run “programName”.

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Task 4 Test

Data to be entered

Reason for test

Expected Result

Actual Result

Number 1

Holyrood burger (2oz)

Normal data

£13.65

£13.65

Normal data

£12.15

£12.15

Normal data

£17.45

£17.45

Normal data

£14.90

£14.90

Normal data

£11.20

£11.20

Normal data

£12.30

£12.30

£12.50

£12.50

£14.10

£14.10

With onions and bacon, delivered 2

Holyrood burger (4oz) With ketchup and Coleslaw

3

Holyrood burger (8oz) With cheese and coleslaw. delivered

4

Angus rare breed (2oz) With onions, ketchup, bacon, cheese and coleslaw, delivered

5

Angus rare breed(4oz) With ketchup and cheese

6

Angus rare breed (8oz) With bacon

7

Royale with cheese(2oz) With onions, ketchup, cheese

8

Royale with cheese(4oz) With ketchup and coleslaw

9

Royale with cheese (8oz)

£19.30

£19.30

10 11

With onions and coleslaw delivered Honest burger (2oz) With bacon and cheese Honest burger (4oz) delivered

£10.30 £14.70

£12.70 £17.10

12

With ketchup and coleslaw Honest burger (8oz) With onions

£13.40

£15.80

13 14

Ranch (2oz) With ketchup and coleslaw Ranch (4oz) delivered With onions, bacon

£13.20 £18.00

£13.10 £18.10

15 16 17 18 19 20

and cheese Ranch (8oz) With cheese and coleslaw Holyrood (8oz) All toppings, delivered Holyrood (4oz) with all toppings, delivered Holyrood (2oz) with all toppings, delivered Holyrood (8oz) no toppings Holyrood (4oz) no

£15.90 £18.85 £16.85 £14.85 £13.45 £11.45

£16.40 £18.85 £16.85 £14.85 £13.45 £11.45

21

toppings Holyrood (2oz) no toppings

£9.45

£9.45

22

Angus (2oz) no toppings

£9.50

£9.50

23


£10.50

£10.50

24


£11.50

£11.50

25

Ranch (2oz) no toppings

£11.40

£11.40

26


£13.40

£13.40

27


£15.40

£15.40

28

Honest (2oz) no toppings

£11.40

£11.40

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29


£13.40

£13.40

30


£15.40

£15.40

31

Royale with cheese(2oz)no toppings

£11.40

£11.40

32


£13.40

£13.40

33


£15.40

£15.40

34

Honest (2oz) all toppings

£13.80

£13.80

35


£15.80

£15.80

36


£17.80

£17.80

37

Ranch (2oz) all toppings

£13.80

£13.80

36


£17.80

£17.80

38


£15.80

£15.80

39


£17.80

£17.80

40

Angus(8oz) all toppings

£11.90

£11.90

41


£12.90

£12.90

42


£13.90

£13.90

42

Royale with cheese(2oz) all toppings

£13.80

£13.80

43


£15.80

£15.80

44


£17.80

£17.80

45

Ranch(2oz) with coleslaw and cheese

£12.40

£12.40

46


£14.40

£14.40

47


£16.40

£16.40

48

Holyrood(2oz) no toppings delivered

£12.45

£12.45

49


£14.45

£14.45

50


£16.45

£16.45

Task 5 private void btnCreditcard_Click(object sender, EventArgs e) { rtbBill.Text += "Testing 1"; txtCost.Text = "Hello..."; MessageBox.Show("finished......"); } private void btnOrder_Click(object sender, EventArgs e) {

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} private void rtbBill_TextChanged(object sender, EventArgs e) { }

This is the code for the text box on Form1. (Note - For some reason it is not working. I think that the text box may be locked)

Task 6 Figure one – This will be the screen that will appear if you don’t enter the staff code correctly MessageBox.Show("Unsuccessful Login..."); txtCode.Text = ""; txtCode.Focus(); if (LoginCount == 3) {

Figure two – This will be the screen that will appear if they enter the correct staff code { MessageBox.Show("Successful Login..."); Log_in.ActiveForm.Close(); return; }// end if

Figure three –If you enter the wrong staff code three times a this message will inform you that you have ran out of login chances. if (LoginCount == 3) { MessageBox.Show("You have run out of login chances... Goodbye"); Application.Exit();

Figure four – This is form 1. It is the main screen for the website ( Note: for some reason the text box is not working)

Figure five – This is the credit card Ronan Cunningham

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screen. The user must enter his/her credit card.

Figure six- This is the log in screen. It will be the first screen the user will see. The user must enter the right code. namespace Test4 { public partial class Log_in : Form { string[] staffArray = new string[3]; int LoginCount = 0; protected override CreateParams CreateParams { get { const int CP_NOCLOSE = 0x200; CreateParams myCp = base.CreateParams; myCp.ClassStyle = myCp.ClassStyle | CP_NOCLOSE; return myCp;

Codes private void Log_in_Load(object sender, EventArgs e) { staffArray[0] = "Jane"; staffArray[1] = "Tim"; staffArray[2] = "Worker"; txtCode.Focus(); } private void txtCode_TextChanged(object sender, EventArgs e)

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unit 14 assignment

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