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Learn about the different phases in software development models including planning, requirements, feasibility, design, construction / creation, testing, implementation (phased / parallel / big bang (crash)), documentation creation and maintenance. Based on Unit F160 (Fundamentals of Application Development) for the OCR Cambridge Advanced National in Computing (H029 / H129) (AAQ - Alternative Academic Qualification). Qualification: Cambridge Advanced National in Computing (AAQ) Unit: F160: Fundamentals of Application Development Certificate: Computing: Application Development (H029 / H129) 2.2 - Phases of Software Development Models Watch on YouTube : Phases of Software Development Models There are seven phases of software development models you need to know. As well as knowing the common phases and the key tasks within each phase , you must also understand how and why phases interact with each other and why they may iterate . Phases of Software Development Models Key Phases Planning (including requirements and feasibility ) Design Construction / Creation Testing Implementation (including phased , parallel and big bang ( crash ) methods) Maintenance Documentation creation Phased Parallel Big Bang Q uesto's Q uestions 2.2 - Phases of Software Development Models: 1. Describe the common tasks in each of the first four phases of software development . [8 ] 2. Explain the three implementation methods : phased , parallel and big bang (crash ). [6 ] 3. Describe the common tasks in the final two phases . [4 ] 4. Explain why it is important that phases interact with each other. [ 2 ] Maintenance is important - as of 2025 , some US air traffic control towers still use and maintain systems using Windows 95 and floppy disks because of their reliability . D id Y ou K now? 2.1 - Software Development Models Topic List 3.1 - Planning Projects

Learn about how images are represented in a computer system, including vector and bitmap graphics, file size, resolution, colour depth and metadata. Based on the 2020 Eduqas (WJEC) GCSE specification. 4.6: Graphical Representation Exam Board: Eduqas Specification: 2020 There are two main types of graphics used in computer systems: raster (also known as bitmap ) and vector graphics. Raster (Bitmap) Graphics Vector Graphics Raster graphics are made up of a grid of pixels . Vector graphics use objects (lines and curves ) to mathematically form shapes. If scaled to a larger size, a vector graphic does not lose any image quality . If scaled to a larger size, a raster graphic loses image quality . Raster graphics are generally larger in file size because data is stored for each pixel . Vector graphics are generally smaller in file size . Examples of raster images include photographs and screenshots. Examples of vector graphics include logos and cartoons. How to Calculate File Size File Size = Resolution x Colour Depth The resolution of an image is the width in pixels multiplied by the height in pixels. x The colour depth (also known as bit depth ) is the number of bits that are used to represent each pixel's colour . 1 bit represents 2 colours (0 or 1 / black or white). 2 bits will allow for 4 colours, 3 bits for 8 colours, 4 for 16 etc. A colour depth of 1 byte (8 bits ) allows for 256 different colours . Remember you must multiply the colour depth , not the number of available colours (e.g. 8 not 256). The RGB (Red , Green , Blue ) colour model uses 3 bytes (a byte of 256 red shades , a byte of 256 green shades and a byte of 256 blue shades ) that together can represent 16.7 million different colours. Example Height = 6 bits Resolution = height x width Resolution = 8 x 6 = 48 bits -------------------------- Colour Depth = 1 bit (only 2 colours) -------------------------- File Size = Resolution x Colour Depth File Size = 48 x 1 = 48 bits File Size in bytes = 48 ÷ 8 = 6 bytes File Size in kilobytes = 6 ÷ 1000 = 0.00 6 kilobytes Width = 8 bits Look carefully at the exam question to see if the examiner is expecting the answer in bits, bytes or kilobytes . Always calculate the file size in bits first then: Divide the file size in bits by 8 to convert to bytes . Divide the file size in bytes by 1000 to convert to kilobytes . Metadata for Graphics Metadata is additional data about a file . Common image metadata includes: Dimensions Colour depth Make Model Orientation Exposure time Metadata is important, For example, the dimensions must be known so the image can be displayed correctly . Metadata for a smartphone-taken picture: width in pixels, e.g. 720 height in pixels, e.g. 480 Q uesto's Q uestions 4.6 - Graphical Representation: 1. Describe three differences between raster (bitmap) and vector images . [ 6 ] 2. How many colours can be represented with a colour depth of... a. 1 bit [ 1 ] b . 5 bits [ 1 ] c. 1 byte [ 1 ] 3. How is the file size of an image calculated? [2 ] 4a. An image file has a width of 10 pixels , a height of 8 pixels and a colour depth of 2 . What is the file size in bytes ? [3 ] 4b. An image file has a width of 120 pixels , a height of 120 pixels and a colour depth of 1 . What is the file size in kilobytes ? [3 ] 4c. An image file has a width of 32 pixels , a height of 21 pixels and a colour depth of 1 . What is the file size in bytes ? [3 ] 5. State what is meant by metadata and give three examples of metadata for a graphics file. [ 3 ] 4.5 Character Sets & Data Types Theory Topics 4.7 - Sound Representation

Test your understanding of string and number handling techniques in Python. Try practice tasks and learn through text and images. Perfect for students learning GCSE Computer Science in UK schools. top Python - Section 9 Practice Tasks Task One It is the national hockey championships and you need to write the program for the TV channel showing the live games. Let the user enter the name of the first country that is playing. Then let the user enter the name of the second country . Shorten country 1 to the first two letters . Shorten country 2 to the first two letters . Bonus: Display the teams in uppercase . Example solution: Welcome to the National Hockey Championships!!! Enter the first country: Montenegro Enter the second country: Kazakhstan Scoreboard: MO vs KA G Task Two In some places, the letter G is seen as an offensive letter. The government want you to create a program to count how many times the letter G appears in a sentence . Let the user input any sentence that they like. You need to count how many g’s there are. Then print the number of g’s there are. Example solution: Enter your sentence: good day! great golly gosh, got a good feeling! There were 7 instances of that awful letter! Task Three A pet shop has just ordered in a batch of new dog collars with name tags. However, there was a mistake with the order and the tags are too small to display names longer than 6 characters . You need to create a program that checks the user’s dog name can fit. Let the user enter their dog’s name . Calculate the length of their name. Use an if statement to see if it is greater than 6 characters . If it is then print – Sorry but our dog tags are too small to fit that. Otherwise print – Excellent, we will make this dog tag for you. Example solutions: Welcome to 'Dogs and Cats' Pet Shop! What is the name of your dog? Miles Excellent, we will make this dog tag for you! Welcome to 'Dogs and Cats' Pet Shop! What is the name of your dog? Sebastian Sorry, our dog tags are too small! Task Four It’s literacy week and the Head of English would like you to create a vowel checker program to ensure that year 7s are using plenty of vowels in their work. Let the user enter any sentence they like. For each letter in the sentence that they have just entered you need to use if statements to check if it is a vowel . You will need to use the OR operator between each statement to separate them. After the for loop you need to print the number of vowels they have used. Example solution: Enter your sentence: Put that thing back where it came from, or so help me! You used 14 vowels in your sentence. Task Five Remember the national hockey championships? Well, the company that hired you just fired you… Never mind though, a rival scoreboard company want to hire you right away. You need to let the user enter two countries like last time. But this time you don’t want to calculate the first two letters, you want to print the last three letters . Example solution: Welcome back to the National Hockey Championships!!! Enter the first country: Montenegro Enter the second country: Kazakhstan Scoreboard: GRO vs TAN Task Six Too many people are using inappropriate names on Instagram so they have decided to scrap the username and will give you a code instead. The code is the 2nd and 3rd letters of your first name , your favourite colour and then the middle two numbers of the year you were born . Let the user input their name, then their favourite colour and then the year they were born. Using their data, calculate their new Instagram name! Example solution: Welcome to Instagram What is your name? Matthew What is your favourite colour? red Which year were you born in? 1987 Your new profile name is: ATRED98 Task Seven Copy the text on the right and create a program that will split the text at each full stop. Count the number of names in the list. Print the longest name. Example solution: The list contains 20 names The longest name is alexandria annabelle.clara.damien.sarah.chloe.jacques.mohammed.steven.rishi.raymond.freya.timothy.claire.steve.alexandria.alice.matthew.harriet.michael.taylor ⬅ 9b - Number Handling 10a - Open & Write To Files ➡

Learn about different types computers such a desktops, games consoles, laptops, smart speakers, smart TVs, smartphones, tablets, augmented reality (AR), virtual reality (VR) and mixed reality (MR) devices. Based on Unit F160 (Fundamentals of Application Development) for the OCR Cambridge Advanced National in Computing (H029 / H129) (AAQ - Alternative Academic Qualification). Qualification: Cambridge Advanced National in Computing (AAQ) Unit: F160: Fundamentals of Application Development Certificate: Computing: Application Development (H029 / H129) 5.1.2 - Types of Device Watch on YouTube : Types of Device Applications can be developed for a range of different devices , each type of device having its own characteristics and common uses . The characteristics of popular devices, such as laptop and tablets , may be well known, but ensure you know the difference between augmented reality ( AR ), virtual reality ( VR ) and mixed reality ( MR ) devices. Types of Device Common Devices Desktops are powerful and customisable personal computers designed for use at a desk . Game consoles are designed specifically for playing video games , usually connected to a TV . Laptops are portable computers with a built-in screen and keyboard , suitable for work on the go . Smart speakers are voice-controlled devices that play music , answer questions and can control smart home gadgets . Smart TVs have internet access , interactive features and apps for streaming and browsing . Smartphones have internet , GPS and Bluetooth connectivity , apps and communication functions . Tablets use a touchscreen larger than a phone, they are more portable than a laptop and good for browsing and media . Augmented Reality (AR ) is technology that overlays digital images or information onto the real world . Virtual Reality (VR ) uses a computer-generated 3D environment that fully immerses the user , usually with a headset . Mixed Reality (MR ) is a blend of AR and VR where digital objects interact with the real world in real time . Q uesto's Q uestions 5.1.2 - Types of Device: 1. Explain the difference between the three types of 'reality ' devices . [3 ] 2. Justify which devices a streaming service should consider for an app . [4 ] 3. Describe the characteristics of any devices not covered in your responses to Q1 and Q2 . [ 5 ] The AR app Pokémon Go was so popular when it released in 2016 that within the first 6 months players had walked a combined 8.7 billion kilometres ( 200,000 trips around the Earth ). D id Y ou K now? 5.1.1 - Human-Computer Inter. Topic List 5.2 - Visual Design Considerations

The list of topics in the 2020 OCR GCSE Computer Science specifications. OCR GCSE Computer Science (J277) These pages are based on the J277 OCR GCSE Computer Science specification . This website is in no way affiliated with OCR . Component One: Computer Systems OCR GCSE Key Term Generator Paper 1 Playlist on YouTube 1. Systems Architecture 1.1a - The CPU 1.1b - Registers & FE Cycle 1.2 - CPU Performance 1.3 - Embedded Systems 2. Memory & Storage 2.1 - Primary Storage 2.2 - Secondary Storage 2.3 - Units 2.4a - Number Systems 2.4b - Binary Addition & Shifts 2.4c - Character Storage 2.4d - Image Storage 2.4e - Sound Storage 2.5 - Compression 3. Networks 3.1a - Network Types & Performance 3.1b - Network Hardware & Internet 3.2a - Wired & Wireless networks 3.2b - Protocols & Layers 4. Network Security 4.1 - Network Threats 4.2 - Preventing Vulnerabilities 5. Systems Software 5.1 - Operating Systems 5.2 - Utility Software 6. Impacts 6.1a - Impacts of Technology 6.1b - Legislation Component Two: Computational Thinking, Algorithms and Programming Paper 2 Playlist on YouTube 1. Algorithms 1.1 - Computational Thinking 1.2 - Designing Algorithms 1.3 - Searching & Sorting Algorithms 2. Programming Fundamentals 2.1 - Programming Fundamentals 2.2 - Data Types 2.3 - Additional Programming Techniques 3. Producing Robust Programs 3.1 - Defensive Design 3.2 - Testing 4. Boolean Logic 4.1 - Boolean Logic 5. Languages & IDEs 5.1 - Languages & Translators 5.2 - Integrated Development Environment

Learn how to delay processes using the sleep command in Python. Try practice tasks and learn through text and images. Perfect for students learning GCSE Computer Science in UK schools. top Python 5b - Sleep Using Sleep To pause a program, import sleep from the time library . Type the word sleep followed by the number of seconds that you wish the program to break for in brackets . It must be a whole number . Below is an example of a program that imports the sleep command and waits for 2 seconds between printing: from time import sleep print ( "Hello!" ) sleep(2) print ( "Goodbye!" ) You can implement the sleep command within a for loop to produce an effective timer that outputs each second waited to the screen: You could also use a variable instead of a fixed value with the sleep command such as below: from time import sleep for second in range (1,11): print (second) sleep(1) from time import sleep seconds = int ( input ( "How many seconds should I sleep? " )) print ( "Going to sleep..." ) sleep(seconds) print ( "Waking up!" ) Sleep Task ( Slow Calculator) Create a slow calculator program that needs time to think in between calculations. Print a message to greet the user , then wait 3 seconds and ask them to enter a number . Wait another 3 seconds and ask them to enter a second number . Wait 2 more seconds , print “Thinking…” then 2 seconds later print the total of the two numbers added together . Example solution: ⬅ 5a - Rando m 5c - Date & Time ➡

Learn about on-site storage and cloud storage methods such as private, public, hybrid and community. Resources based on Unit F161 (Developing Application Software) for the OCR Cambridge Advanced Nationals in Computing (H029 / H129) AAQ (Alternative Academic Qualification). Qualification: Cambridge Advanced Nationals in Computing (AAQ) Certificate: Computing: Application Development (H029 / H129) Unit: F161: Developing Application Software 1.3 - Storage Watch on YouTube : On-Site Storage Cloud Storage Locations Cloud Storage Types There are five types of on-site (local ) storage you need to know - file servers , network attached storage (NAS ) devices, portable storage devices, solid state drives (SSD ) and storage area networks (SAN ). In regards to cloud storage , you need to know the different locations (private , public , hybrid and community ) and types (file , object , block , elastic /scalable and cloud-based database services . You need to be aware of the characteristics , advantages and disadvantages of each storage location and type as well as the factors to consider when selecting a storage location and type . What You Need to Know On-Site Storage ? YouTube video uploading soon Cloud Storage Locations ? YouTube video uploading soon Cloud Storage Types ? YouTube video uploading soon Q uesto's Q uestions 1.3 - Storage: 1. What? [2 ] 2. What? [1 ] 3. What? [1 ] 4. What? [1 ] ? D id Y ou K now? 1.2 - Devices Topic List 2.1 - Data Formats & Types

Learn about the main character sets - ASCII (American Standard Code for Information Interchange) and Unicode. Also, discover the five data types - character, string, integer, real and Boolean. Based on the 2020 Eduqas (WJEC) GCSE specification. 4.5: Character Sets & Data Types Exam Board: Eduqas Specification: 2020 What is a Character Set? A character set is a table that matches together a character and a binary value . Character sets are necessary as they allow computers to exchange data . Two common character sets are ASCII and Unicode . ASCII Unicode ( American Standard Code for Information Interchange ) 0100 0001 0100 0010 0100 0011 Uses Binary 128 Tiny Set of Characters Less Memory Required Per Character U+0042 U+0055 U+004E Uses Hexadecimal 36,536+ Large Set of Characters More Memory Required per Character What are the different data types? When programming, variables should be given appropriate data types . Character String Integer A single character , such as a letter, number or punctuation symbol. Examples: A sequence of characters , including letters, numbers and punctuation. Examples: A whole number . Examples: T 8 ? Harry Waters 14:50pm Ice Age 4 475 -8432 56732 Real Boolean Telephone numbers are always stored as a string , not an integer. True / False Yes / No 0 / 1 An answer that only has two possible values . Examples: A decimal number . Examples: 65.3 -321.1234 909.135 Be careful with punctuation. 32.10 is a real but £32.10 is a string. Q uesto's Q uestions 4.5 - Character Sets & Data Types: 1. What is a character set and why are they needed ? [ 2 ] 2. Describe 3 differences between ASCII and Unicode . [6 ] 3. State the 5 different data types . [ 5 ] 4. State which data type is most suitable for the following variables: a. Age [ 1 ] b. Surname [ 1 ] c. Height (in metres) [ 1 ] d. First Initial [ 1 ] e. Phone number [ 1 ] f. Right-Handed? [ 1 ] 4.4 Arithmetic Shift Theory Topics 4.6 - Graphical Representation

Test your understanding of subroutines (procedures and functions) in Python. Try practice tasks and learn through text and images. Perfect for students learning GCSE Computer Science in UK schools. top Python - Section 7 Practice Tasks Task One Example solution: Create a program with three different subroutines (procedures ). One subroutine asks the user their name and prints a response. The second asks for their age and prints a response. The third asks for their favourite colour and prints a response. Remember to write subroutines before the main program. Task Two Create a program that asks a user to input the length of a side in a square. Write a function that takes this value and returns it to be printed. Example solution: Task Three Example solution: Create a program that takes 3 inputs from the user – a name, a villain and a place. Write a function that outputs a story using the user’s answers. Task Four Create a calculator program that uses four different subroutines (add, subtract, multiply and divide). In the main program ask the user to make a choice of which operator to use and then to enter two numbers. Keep looping until the user types stop. Use the 'Using Subroutines as a Menu' section in the 7b to help you. Example solution: ⬅ 7b - Functions 8a - Using Lists ➡

Learn how to create and use a simple graphical user interface (GUI) in Python. Try practice tasks and learn through text and images. Perfect for students learning GCSE Computer Science in UK schools. Python 11 - GUI Graphical User Interface In Python, you don’t have just to use a text display; you can create a GUI (Graphical User Interface ) to make programs that look professional. This page demonstrates the basic features of Python’s built-in GUI named tkinter . You can add images, labels, buttons and data entry boxes to develop interactive programs . Hyperlinked sections covered on this page: Setup: Title, Size & Background Creating Elements: Labels, Entry Boxes, Buttons, Images, Message Boxes Displaying Elements: Pack, Place, Grid Inputs & Outputs GUI Tasks Setup Setup: Title, Size & Background Firstly, import the tkinter command and set tkinter.Tk() to a variable such as window . GUI code can be quite complicated with multiple elements so it is sensible to use a comment for each section. Setting the title , size and background colour of your window is optional but can be easily set up at the start of your code. The .geometry() command sets the size of the window. The first number is the width , and the second number is the height . The .configure() command can be used to set the background colour . For a full list of compatible colours, check here . import tkinter #Setting up the Window window = tkinter.Tk() window.title( "Graphical User Interface" ) window.geometry( "400x400" ) window.configure(background = "lightblue" ) import tkinter #Setting up the Window window = tkinter.Tk() window.title( "Example Number Two" ) window.geometry( "300x400" ) window.configure(background = "darkorchid3" ) Creating Elements Creating Elements: Labels, Entry Boxes, Buttons, Radio Buttons, Images, Message Boxes Labels label1 = tkinter.Label(window, text = "Hello there" ) label1 = tkinter.Label(window, text = "Hello there" , fg = "black" , bg = "lightblue" , font = ( "Arial" , 12)) Simple label with default formatting: Label with custom formatting: No elements will appear in your window until you write code to put them there. See the 'Displaying Elements' section further down. Entry (Text) Boxes Simple entry box with default formatting: entry1 = tkinter.Entry(window ) Entry boxes will appear blank , the 'Example Text' shown in the images has been typed in. Entry box with custom formatting: entry1 = tkinter.Entry(window, fg = "blue" , bg = "gray90" , width = 12, font = ( "Arial" ,12)) Buttons The command property of a button is a subroutine that will be called when the button is pressed . The subroutine must be written above the button creation code. def ButtonPress (): #Code here runs when the button is pressed button1 = tkinter.Button(window, text = "Click Me" , fg = "black" , bg = "gold2" , command = ButtonPress) Radio Buttons The Radiobutton element is a multiple-choice option button . A variable needs to be created to track which option has been selected, in this example it is ‘choice ’. Each radio button needs to be linked to the variable and given a unique value (e.g. 0, 1, 2). The radio button with the the value of 0 will be automatically selected when the window opens . Although not shown below, the .set() command can also be used to select a specific radio button , e.g. choice.set(2) . choice = tkinter.IntVar() radio1 = tkinter.Radiobutton(window, text = "Breakfast" , variable = choice, value = 0) radio2 = tkinter.Radiobutton(window, text = "Lunch" , variable = choice, value = 1) radio3 = tkinter.Radiobutton(window, text = "Dinner" , variable = choice, value = 2) Message Boxes You need to import messagebox from tkinter before you can use message boxes . You only need to do this once in your program and it sensible to have it at the very start after you import tkinter (and any other libraries). from tkinter import messagebox tkinter.messagebox.showinfo( "Information" , "Welcome to the program!" ) tkinter.messagebox.showerror( "Error" , "There is a problem with the program." ) if (tkinter.messagebox.askyesno( "Warning" , "Have you understood the instructions?" )) == True : tkinter.messagebox.showinfo( "Warning" , "Thank you for understanding." ) else : tkinter.messagebox.showinfo( "Warning" , "Please read the instructions again." ) Yes / No Message Box Clicking Yes (True ) Clicking No (False ) Images Tkinter supports the image file types .png and .gif . The image file must be saved in the same folder that the .py file is. Resize the image in separate image editing software such as Paint to a specific size . Tkinter does not support all image file types, such as .jpg. Use an application like Microsoft Paint to save an image with a different extension like .png. photo1 = tkinter.PhotoImage(file = "hamster.png" ) photoLabel1 = tkinter.Label(window, image = photo1) An image can be turned into a clickable button rather than a label. def ButtonPress (): #Code here runs when the button is pressed photo1 = tkinter.PhotoImage(file = "hamster.png" ) button1 = tkinter.Button(window, image = photo1, command = ButtonPress) photo1 = tkinter.PhotoImage(file = "hamster.png" ) window.iconphoto( True , photo1) The icon of the window can be changed to an image . Displaying Elements: Pack, Place and Grid Pack .pack() puts the element in the centre of the window, with the next packed element immediately below. window.mainloop() should always be your last line of code in every program, after you have packed, placed or gridded your elements. Displaying Elements labelAdd.pack() buttonAdd.pack() labelMinus.pack() buttonMinus.pack() window.mainloop() Place The .place() command allows an element to be placed in specific coordinates , using x (horizontal ) and y (vertical ) axes. labelAdd.place(x = 25, y = 15) buttonAdd.place(x = 12, y = 35) labelMinus.place(x = 90, y = 15) buttonMinus.place(x = 83, y = 35) window.mainloop() Grid The .grid() command is used to create a grid system to set the row and column . Remember Python starts counting at 0 . You can use padx and pady to add extra space (x is horizontal , y is vertical ). labelAdd.grid(row = 0, column = 0, padx = 10, pady = 5) buttonAdd.grid(row = 1, column = 0, padx = 10) labelMinus.grid(row = 0, column = 1, padx = 10, pady = 5) buttonMinus.grid(row = 1, column = 1, padx = 10) window.mainloop() Inputs & Outputs Inputs and Outputs .config to Change an Element .config() overwrites the property of an element. It can be used with elements such as labels and buttons to change how they appear. label1.config(text = "Warning!" ) The example below (not showing setup and packing) adds 1 to a total variable when the button is pressed . Config is used in two ways: to display the updated total and to change the background of the label to green. def AddOne (): global total total = total + 1 labelTotal.config(text = total, bg = "green" ) total = 0 buttonAdd = tkinter.Button(window, text = "Add" , command = AddOne) Below is a similar program in full that increases or decreases and displays a total when the buttons are pressed . #Setup import tkinter window = tkinter.Tk() total = 0 #Button Presses def AddOne (): global total total = total + 1 labelTotal.config(text = total) def MinusOne (): global total total = total - 1 labelTotal.config(text = total) #Create Elements labelTotal = tkinter.Label(window, text = total, font = ( "Arial" ,14)) buttonAdd = tkinter.Button(window, text = "+" , width = 6, bg = "green" , command = AddOne) buttonMinus = tkinter.Button(window, text = "-" , width = 6, bg = "red" , command = MinusOne) #Display Elements buttonAdd.pack() buttonMinus.pack() labelTotal.pack() window.mainloop() .get to Input a Value .get() returns the value of an element such as an entry box , label or the choice variable if using radio buttons . The value of the element should be stored in a variable so it can be used elsewhere, for example: name = entryName.get() number = int (entryNumber.get()) Use int when getting a value that is an integer : The full program example below checks that the values typed into the username and password entry boxes are correct . Error Messages #Setup import tkinter from tkinter import messagebox window = tkinter.Tk() window.title( "Login" ) #Button Presses def CheckDetails (): username = entryUsername.get() password = entryPassword.get() if username == "Bob Bobson" and password == "cabbage123" : tkinter.messagebox.showinfo( "Success" , "Welcome " + username) else : tkinter.messagebox.showerror( "Invalid ", "Those details are incorrect." ) #Create Elements labelUsername = tkinter.Label(window, text = "Username:" ) labelPassword = tkinter.Label(window, text = "Password" ) entryUsername = tkinter.Entry(window) entryPassword = tkinter.Entry(window) buttonLogin = tkinter.Button(window, text = "Login" , command = CheckDetails) #Display Elements labelUsername.grid(row = 0, column = 0) entryUsername.grid(row = 0, column = 1) labelPassword.grid(row = 1, column = 0) entryPassword.grid(row = 1, column = 1) buttonLogin.grid(row = 2, column = 0) window.mainloop() .bind for Key Presses (& Close Window) .get() will run a specific function when a certain key is pressed. The name of the key must be surrounded by < > brackets and speechmarks . Any associated subroutine of a key bind will need a parameter : event has been chosen and set to None . The code below closes the window using the .destroy() command when the Esc key is pressed. def Close (event = None ): window.destroy() window.bind( "" , Close) The code below will activate the button (and display a message box) by clicking on it but also by pressing the Enter ( Return ) key . def ButtonPress (event = None ): tkinter.messagebox.showinfo( "Success" , "The button was activated" ) button1 = tkinter.Button(window, text = "Press Me" , command = ButtonPress) window.bind( "" , ButtonPress) GUI Tasks GUI Programs to Make Making a program using a GUI can be overwhelming and you must decompose the problem - take it step by step : Import tkinter and create the window (set the title, size and background colour). Create the elements you will need such as labels , buttons and entry boxes . Put the components in the window using pack , place or grid . Write the subroutines for any button presses . These are written at the top of the program after the window setup. Consider your variables - do any need to be set at the start ? Have you made them global if they’re needed within a subroutine ? Put window.mainloop() as the final line of code, only have it once. Use #comments in your code to break up the different sections, the key four sections are shown below. #Setup #Button Presses #Create Elements #Display Elements GUI Task 1 (Random Number Generator ) Generate a random number between 1 and 100 when the button is pressed and display it in a label. Extension idea: Use entry boxes to allow the user to manually input the minimum and maximum value. Example solution: GUI Task 2 (Currency Exchange ) Enter a decimal value and convert it from British pounds to American dollars. You can search for the current exchange rate. Extension idea: Show the conversion rate for other currencies such as Euros and Japanese Yen. Example solution: GUI Task 3 (Random Quote Generator ) Create a list of quotes and use the choice command from the random library to select one to be displayed in a label when the button is clicked. Extension idea: Have a separate text box and button to add more quotes to the list. Example solution: GUI Task 4 (Colour Changer ) When the button is clicked change the background colour of the button with .config to the RGB colour code in the entry box. This should be # followed by 6 hexadecimal values (0-9, A-F). Extension idea: Have an error pop up in a message box if the colour code is incorrect - it must be exactly 7 characters long and start with a hashtag. Example solutions: GUI Task 5 (Class Captain Votes ) Use radio buttons to vote for different candidates in a class vote. Use an if statement when the button is pressed to check which radio button is selected using .get() and the variable you've assigned to the radio buttons ('choice' if you've followed the code in the radio buttons section on this page). Use .config to overwrite a label's value. Remember any variables you want to use in subroutines must be globalised. Extension idea: Stop the count after a certain number - e.g. 30 votes recorded. Example solution: ⬅ Section 10 Practice Tasks 12 - Error Handling ➡

Test your understanding of selection (if statements) and operators (mathematical and logical). Try practice tasks and learn through text and images. Perfect for students learning GCSE Computer Science in UK schools. top Python - Section 4 Practice Tasks Task One: Spanish Numbers Create a very simple Spanish translation program. Let the user enter a number between one and four then print the Spanish word for that number using if , three elif s and else . One in Spanish is uno , two is dos , three is tres and four is cuatro . If they enter anything else print “I only know 1 to 4 in Spanish!” . Example solutions: Enter a number between 1 and 4: 3 tres Enter a number between 1 and 4: 5 I only know 1 to 4 in Spanish! Task Two: School Trip A school is organising a trip to Alton Towers . The coaches they are hiring can fit 45 people . Enter the total number of people going on the trip and work out how many coaches will be full (using integer division ) and how many people will be left over on a partly full coach (using modulo division ). Example solutions: How many people are going on the trip? 100 There will be 2 full coaches and 10 people on another coach. How many people are going on the trip? 212 There will be 4 full coaches and 32 people on another coach. Task Three: Driving Tractors There are different rules in the United Kingdom for what farmers at certain ages can drive . Ask the user to input their age and then output the relevant information below: Children under 13 cannot drive any tractors. A trained and supervised 13 to 15 year old can drive a low-powered tractor on private flat grass. 16 year olds with a provisional category F licence can drive tractors less than 2.45 metres wide. Young adults from 17 to 20 with the correct licence and training c an drive tracked vehicles that weigh less than 3,500kg. Adults over 21 years old , with the correct licence and training, can drive all types of tractor. Note: Always be safe around machinery in farms regardless of your age. Driving without adequate training and a licence is illegal. Example solutions: How old are you? 8 You cannot drive any type of tractor. How old are you? 13 If you are trained and supervised you can drive a low-powered tractor on private flat grass. How old are you? 19 With the correct licence and training you can drive tracked vehicles that weigh less than 3,500kg. Task Four: Avoid the Three Choose a category like planets , people in your class or months of the year. Secretly choose three of them . Ask the user to enter a word in your category. If they enter one of the three that you chose, they lose . Example solutions: I have secretly selected three months you must avoid! Enter a month of the year: April AHA! You chose one of the secret months, you lose! I have secretly selected three months you must avoid! Enter a month of the year: December Well done, you didn't choose one of my three! ⬅ 4c - Logical Opera tors 5a - Random ➡

Learn how to start a new Greenfoot program and set up the world and actors ready for the next steps in creating a game. Part 1 of the Greenfoot Tutorial for the Eduqas/WJEC GCSE 2016 specification. 1. Setup & Populating the World Greenfoot Tutorial 1. Open Greenfoot This tutorial uses Version 2.4.2 which is the version students are given to use in the WJEC/Eduqas Component 2 exam . Click here for more information and how to download 2.4.2 . If you are using a more recent version the code should still work but the look of the program in the screenshots may be different. In the Component 2 exam of the 2016 WJEC/Eduqas specification you would skip ahead to the New Object Placements stage further down this page as the classes should be set up for you. Watch on YouTube: 2. New Scenario For a new project, click ' Scenario ' and then ' New '. If you are using a more recent version of Greenfoot select ' New Java Scenario '. Save this new project in a suitable location such as a folder named 'Greenfoot' . You may wish to save this project as ' SimpleGame ' or ' ExampleGame '. 3. Setup the MyWorld class The first thing to do is to create a subclass of World called MyWorld which becomes our background object. Right-click on the World class and select 'New subclass... ' Set the New class name to MyWorld . Choose any image from the 'backgrounds ' image category. I have chosen the 'cell.jpg ' image. Click the Compile button in the bottom right of the Greenfoot window to save the program . 4. Create the Main Character class Now to create a new class for the main character. Right-click on the Actor class and select 'New subclass... ' Give the new object an appropriate name and choose a relevant image . I have named my class 'Sheep ' and selected the sheep.png image. 5. Right-click on Actor and create two more classes: Collectable objects to pick up (e.g. my orange) An enemy character to avoid (e.g. my elephant) Don't forget to compile the program. Watch on YouTube: After creating your classes you must move them over to the game world. This is known as populating the world . 1. New Object Placements Right-click on your main character object and select the top option e.g. 'new Sheep()'. Drag your mouse to the world and click to drop it. Complete the following actions: Place 1 main character object. Place 5 collectible objects. Place 2 enemy objects. 2. Save the World Once you have populated your world with objects then right-click anywhere on the background and select 'Save the World '. This saves the positions of each object so that it won't reset every time you start a new game. You can close the MyWorld code that automatically opens when you save the world, we never add any code to this window. Part 2 - Movement (Arrow Keys) >