Programming in Visual Basic - Essay Example

Individual Learning – Visual Basic 1. Introduction Automated processes and screen displays helps students easily analyse problems and increase their speed and accuracy. They learn to explore patterns and relationships by changing variables and rules to control and monitor situations. Visual Basic is a powerful yet flexible programming language where you can easily develop fully functional applications. As an event-driven programming language, it allows developers to make full use of the graphical user interface (GUI) for drag and drop application development. This paper will explore ICT with Visual Basic in relation to the National Curriculum requirements. Develop an application using Visual Basic’s form and tools. Develop and a scheme of work and detailed series of lessons in accordance with the key aspects of ICT. 2. Information and Communication Needs and Visual Basic Generally, one must be aware of the information and communication needs of their own subject area. According to Leask and Pachler (2005), the degree to which a subject requires the retrieval and processing of information and the communication of ideas and knowledge will determine the range of work one would likely to undertake. In England and Wales, awareness of the demand of the National Curriculum with regard to information technology and your own school’s requirements for the delivery of skills in ICT (p.5). The National Curriculum programmer of study for ICT groups the knowledge, skills and understanding that pupils need to acquire into four themes. The Key Stage 3 Strategy or the Framework for teaching ICT capability for year 7, 8, and 9 are subdivided into three key concepts. The first is concerned with finding information and judging the quality of content retrieved. These include the validity, reliability, and bias of various data and information sources, and selecting relevant information required for a particular task. They must know how different information is combined to convey meanings. As a method of search, pupils are taught to use search engines that includes how to refine searches and finding the right information. Finally, pupils are taught to investigate and organise information. They must learn to retrieve and collect information for a specific purpose and they must the data in various ways to find something out, draw conclusions or answer hypotheses, and present their findings effectively. To develop and display information efficiently, pupils are taught to analyse problems, breaking them down into component parts, and to automate processes to increase their speed and accuracy. They can use models to present a scenario or processes on screen. They learn to explore patterns and relationships by changing variables and rules and can use this technique to answer various questions. Pupils are taught to develop computer-based systems to control and monitor situations, and analyse the problem and design, create, test and refine a solution. For instance, they may develop a system to measure temperature, light, and humidity with various subroutines to control sensors. When exchanging and sharing information, they must recognise a common forms and conventions used in communications and to use this knowledge to present information appropriately to specified audience. They must know how to consider fitness for purpose and review and evaluate the effectiveness of their work and would be able to justify the choices they have made. Critically evaluate these choices to develop and improve their presentation of information, refining it for the purpose and audience (Dfes-A, 2007:1). How the National Curriculum in IT is delivered depends on the school’s approach. In some schools according to Leask and Pachler (2005), the whole staffs are involved in delivering IT across the curriculum. Achievement in IT capability will not happen by accident. Pupils need to be taught new techniques and offered opportunities to try them out and to compare the effectiveness of using IT with other methods of working. These opportunities need to be offered in a coherent manner. Pupils are unlikely to be given opportunities to use IT in all areas of the curriculum unless this is carefully planned and co-ordinated (p.12). With the speed of ICT, pupils gain a response immediately. The response will be the same as a teacher would provide, but it is often enough to enable the pupil to continue with confidence. Its interactivity, visual display or sound will be produced when the pupil chooses an option in a quiz enters some data into a spreadsheet or type a word in passage of text. Other features of ICT can help as for many learners, routine task such as writing and calculating are difficult and daunting. Consequently, they find it hard to focus on the mode specific ideas that you are trying to teach. Through the automatic features of ICT, such routine task is easy with voice input and clicking menu options to avoid the laborious entry of text. For instance, spreadsheet can quickly produce a graph, which would have taken most of the lesson previously. They will often gain in accuracy too. This combination of features is very powerful and promotes a continued engagement with the activity thus; learners will persevere longer with ICT tasks (Kennewell 2004:23). Experimenting and producing interactive materials, a number of different types of software allow you to exploit ICT's interactivity to provide advantages over other ways of achieving these purposes. The tools you choose for this purpose should be used thoughtfully to create material for pupils that provides features, which cannot easily be obtained with paper-based materials. Visual Basic or C++ is suitable software for this since it is the most powerful and flexible option but requires some serious study to learn and makes implementation hard work (Kennewell 2004:156). 2.1 Visual Basic Visual Basic was introduced in the early 1990s and since then it greatly simplified Windows application development. Visual Basic versions continue to provide a programmer-friendly environment in which you can write powerful desktop, web-based, and mobile applications quickly and easily. For instance, if you need to develop a Windows Form application that converts between the Fahrenheit, Celsius, and Kelvin temperature systems, you just have to create a Windows Forms application, and add the appropriate controls and logic (Patrick 2006:1). In our case, easy knowledge audit for students is our goal and with a database application managing our data in records and fields, thing would be a lot easier. However, the database does not necessarily store your data in records and fields in a table-like format, but the database makes the data appear to the program in that format. Visual Basic takes advantage of this format and retrieves data in the record and field format no matter how the database physically stores the data. With Visual Basic built-in data control, user can modify the data that the Data control display, and the Data control makes sure that the changes are made to the underlying database through bound controls. If you do not want the user to be able to change data displayed from a Data Control, you can use a label and not a text box to display the database data. You can bind several other controls to the Data controls and make the control read-only so that the user cannot change the underlying database (Perry and Hettihewa 1998:245). Generally, using the advance feature of Visual Basic, the basic process for accessing data is to open a connection to a database using a Connection object, and then use a DataAdapter object to execute an SQL query against the database and stream the data into a DataTable inside a DataSet object. The basic process for updating a database from data residing in DataTable inside a DataSet is open a connection, then execute the Update method of the DataAdapter object and reference the DataSet object containing the data you wish to update. You can also execute stand-alone SQL statements that update data (Insert, Update, Delete) by using a Command object directly. Both the processes for reading and updating can use stored procedures instead of SQL statements (Holzner and Howell 2002:3). Having the reputation to be the easiest and the quickest way to develop fully functioning applications for even for older versions of Windows, it allows developers to make full use of the graphical user interface (GUI). It provides numerous tools for developing the different aspects of applications that the GUI interface. A Visual Basic programmer develops an application in three main stages. First is to produce graphical user interface by drawing objects onto forms. Second, is to refine the appearance and behaviour of these objects by setting their properties. Third, is to identify the actions of the user in using the graphical interface and attach code to the events that can subsequently occur (Jones 2001:1). Visual Basic is referred to as an event-driven programming language. Traditional programming such as Pascal is referred to as procedural programming. Procedural code consists of sequence, selection, and repetition. All program actions are dictated by the execution of program statements. An “event” is an action to which an application responds. For instance, a key press or mouse move. Event-driven programs, like procedural programs, consist of sequence, selection, and repetition. However, program statements are executed only upon the occurrence of an event. An even-driven installation program allows the user to interrupt the installation process. Unlike procedural programs, the installation program with even-driven programming language is no longer in total control of what happens because it allows the user to interrupt, the program responds to outside “events”. The fundamental difference between this and procedural coding is that the use is given the chance to interrupt the operation of the program. At its simplest level, this describes an event-driven program (Jones 2001:2). When writing an even-driven program the programmer does not know in advance which option a user will choose. The programmer’s responsibility is to attach appropriate code to all of the possible events. In Visual Basic, an “object” is a self-contained combination of code and data that can be treated as a unit. Within Visual Basic, an object can be a form, a control, or an entire application. A design-time form is referred to as a Window at run-time. A form will have associated code and data, it also has associated properties, events to which it will respond and methods. The properties of a form are responsible for changing its appearance such as background colour and other features of the form. Associated with the form are methods that can act upon it. For instance, the “Hide” method removes the form from view by settings its visible property to false. The “Click” and “Double Click” even are examples of events to which a Window (Form) will respond (Jones 2001:7). The interface elements of the Visual Basic design environment contain a menu bar, toolbar, toolbox, form, project window, properties window, and the object browser. In Visual Basic, it is normal for all the interface elements to be overlapping each other. Each interface element can be closed until required by the programmer by clicking the “x” in the windows top right corner. The menu bar contains commands used to build an application group in eight main menu headings. The files, edit, view, insert, and run, tools, add-ins, and help (Jones 2001:22). Forms are fundamental to the development of application using Visual Basic. They are the foundation for creating the GUI. A form can act as a window, a dialogue box or as a container for ‘storing’ objects to be used in other windows. Objects from the toolbox are drawn onto forms to create the desired user interface. When starting a new project with Visual Basic, choose “New Project” from the File menu. A new form will open (Form1 by default) where you can objects from the toolbox. Saving a form is as easy as clicking a mouse and choosing Save File from the File menu. Choose a suitable name with an .FRM extension and click OK. The form will be supplied as we mention earlier with a default name (Form1), however, it is a sound practice to choose a suitable name that reflects the purpose of the form. Also, ensure that the form is saved in a suitable folder that has a name that reflects the purpose of the application under development. In the same way, it is also advisable to store every project and its associated files in its own directory or folder (Jones 2001:23). The most common properties of a form are its name and caption. The caption property of a form dictates what appears in its title bar. The name property of a form identifies it as an object with the project. It is a good programming practice to set the Name property of a form and controls to reflect their function within an application. For instance, a form used to interface to a database would have it name reflect this and obviously a sensible name would be DatabaseInterface. However, if the form was named DatabaseInterface and programmers read the program code they would have no way of knowing the type of object referred to. The way around this problem is to prefix every sensible name setting with three lower-case letters to reflect the type of object. For a form these letters are “frm”, consequently, the name DatabaseInterface would become frmDatabaseInterface. This setting may appear to be too large and it could be abbreviated, however, it is difficult to read and understand code a number of weeks after it has been produced and the best way to document code is to use descriptive settings for objects and variables (Jones 2001:41). In a typical computer system model, program and data are in separate area. The program area is responsible for storing the program instructions to be executed and the data are stored the variables to be manipulated by the instructions. The syntax of procedure whether it is an even or general, reflects this division of program instruction and data. Immediately after the heading of a procedure, the data to be manipulated is declared. Following the data declaration are the program instructions. Variables in a procedure are declared after the keyword ‘Dim”. The keyword is derived from the word dimension, which in turn is derived from early Basic to describe the setting aside of memory area to be used for the program data storage. It is normal to fixt the data type of the declared variable and this is achieved by using the reserved word 'A 'and some other type such as integer etc. Once the interface is developed, the next step is to attach the code to all of the events. Consequently, it is necessary that all of the possible events be identified. Some of the events are obvious but some are more subtle. Indeed, it is often difficult to anticipate all of the events that are required for an application. It is only during development that the more subtle events become apparent. However, with experience most events can be predicted. Events come from two main sources, the user, and the system. It usual practice firstly to identify the events generated by the user (Jones 2001:56). In connection with the National Curriculum for Key Stage 3 and 4, the aim of developing ideas and making things happen is achievable through automated ICT processing. Visual Basic offers a wide range built-in function for problem analysis and exchanging and sharing information. It generates the motivation and engagement and facilitates improvement of work. Visual Basic has excelled as a rapid application development (RAD) environment for corporate and commercial applications. Furthermore, it offers programming language and development environment noted for its simplicity and ease of use, making it an extremely attractive choice for those new to programming (Patrick 2006:3). Building a Visual Basic application is simple. Let us make an application called “Area of a Circle”, a simple program automating the computation of a circle’s area. Figure 1.0 The above figure shows how an application is created using a Visual Basic form and toolbox. We change the form’s title into something relevant by changing its caption properties. We drag and drop the circle and command button from the toolbox and replaced the properties according to our requirements. The command button will act as a trigger to compute thus we renamed it to “Compute” (see snapshot below) and we inserted a text box to accept our input for the value of radius (A=π x r2). Figure 2.0 The area of a circle is the number of square units inside that circle. For instance, if every square in the circle has an area of 1 cm2 we could count the total number of squares to get the area of the circle. Therefore, if there were a total of 12.8 squares, the area of the circle would be 12.8cm2. If we want to find the area of a circle with a radius of 3 inches, we can use the formula A= π . r. .r where A- 3.14 multiplied by 3 inches and multiplied by 3 inches ( 3.14 * 3 * 3). We will code this formula using Visual Basic command and variable declaration: Private Sub Command1_Click() Dim A As String Dim r As Integer Dim p As String p = 3.14 r = Val(Form1.Text1.Text) * Val(Form1.Text1.Text) A = Val(p) * r Form1.Label2.Caption = Val(A) End Sub The idea is to type the value of r to the radius text box and let the program compute for the value of A. The image of a circle will show the results of the computation. The snapshot below shows the declaration of variables in the Command1 window. Figure 3.0 These codes are inserted in the command button’s (‘Compute’) event properties where A (Area) is declared as a string type. The r or radius as an integer and p as a string. Label2 of form1 will hold the value of area after computation. Figure below illustrates how this application will function. Figure 4.0 When the application runs, we typed a value of 4 as an input to the radius text box then we clicked the ‘Compute’ button to execute our computing statements. The area of circle is displayed at the centre of the circle with a value of 50.24. 2.2 Scheme of Work and Series of Lessons Looking back at the fundamental elements of Visual Basic programming, creating a user interface is quite challenging thus it attracts attention and generates engagements. Moreover, manipulating variables and creating functions generates motivation for further learning since it continually demands improvement of work. Creating a scheme of work based on the principles for constructing a scheme of work set by Dfes needs to take into account the circumstances of the school and its aims and purposes. It must be a whole-school plan approved by all staff. It is helpful to think about the key aspect of IT when developing scheme of work from the National Curriculum Order for IT since there should be a balance between the sections of the programmes of study. Think about the IT techniques that need to be taught in support of this scheme. How appropriately it should be sequenced and how to check children’s progress. There are many things to consider but taking into account the skills, techniques, key ideas, progression, checking and assessment, and practicality is definitely helpful (Dfes-B 2007:1). In Visual Basic, after introducing the basics of database concepts, the teacher should concentrate on setting the scene and outlining the significant features of Visual Basic. The outline should include the basic input/output statements for programming tasks. Second are the control statements where pupils can learn several statements for controlling the flow of execution. Third is working with forms where pupils can learn basic of customizable form properties. Fourth is handling variables and arrays, manipulation of various variable types such integer, word, string, etc. and dimensioning arrays. Fifth is learning the difference between VB’s functions and procedures, creating and automating tasks through VB’s powerful programming codes and controls. Sixth is to learn embedding pre-built functions like the Active x Controls and more importantly, database programming with Visual Basic as seventh. On a more advance stage, learn to interface with Active Data and Scripting Objects and finally, Visual Basic programming for the Web. The series of lessons can start with creating a simple form to add two numbers using textboxes and buttons. This exercise will enable pupils to learn the relations between objects and their corresponding properties. Another is to create a simple form to perform other arithmetic computations (multiply, divide, subtract). A form to display table of a given integer or a form which generates series of numbers within given limits using FOR LOOP or DO WHILE iteration statements. Find factorial of N using any loop statement, read value from a text box and write it in another text box. Define a programme to read use salary from a text box and calculate its tax depending upon the bracket in which if falls using if-elseif-endif. Create a function, which returns areas of circle of a given radius, or use a form to save/retrieve data from use in text box and save it to a table. Use text boxes, combo boxes, tree-list to save/retrieve data from table. Use different property sheets to change appearance and format of text item. Lastly, use property sheet to modify form background properties. To keep track of the processes, it is useful if the methods used to monitor ICT work are comparable to those used with Ofsted so that the school’s monitoring would produce the same picture, as Ofsted would find, were ICT to be inspected. The two significant sources of evidence for monitoring progress in ICT are pupil’s works and observing ICT lessons. Pupils work will form the basis of a discussion with a teacher about progress towards target levels of attainment. Observing lesson is common practice now in schools and the key to school monitoring is agreeing the criteria for the observation prior to the observation and treating the process as about sharing views on good professional practice rather than ‘inspecting’. “Monitoring is not about checking up on teachers, it is about reviewing the impact of teaching on learning” (Naace 2007:1). It is therefore necessary to monitor and evaluate pupil’s performance based on the accumulated knowledge towards target levels of attainment. 3. Conclusion When designing information and communication application, a teacher must first evaluate the specific ICT needs of their subject area. This is necessary since the extent of work depends on the amount required to process ICT ideas and knowledge. The National Curriculum for ICT set three key concepts for teaching ICT and these includes finding information and judging the quality of content. This means checking the validity, reliability, and bias of various data and information sources, and choosing relevant information required for a particular task. Using search engines, learning how to refine searches, and retrieving the right information. Investigate and organise information, learning to retrieve information for a specific purpose, analyse that data and draw conclusions from it. However, National Curriculum for ICT delivery depends on the school’s approach but it should be carefully planned and coordinated. Through the automatic features of ICT, experimenting and producing interactive materials is easy. However, the tools you choose for this purpose should be uses thoughtfully to create material for pupils that provides features that is not available with paper-based materials. Visual Basic is suitable since it is a powerful but flexible programming environment. With a reputation of being the easiest and quickest way to develop fully functional applications, it provides a versatile Graphical User Interface (GUI). Moreover, it has a number of tools for developing applications using the GUI. A programmer can produce a GUI by drag and dropping objects onto forms and change the appearance and behaviour of these objects through their properties. Visual Basic is an event-driven programming language and therefore it responds to external calls or events like the key press or a mouse movement. This means that program statements are only executed upon the occurrence of events. Forms are fundamental to Visual Basic, as they are the foundation for building GUI. In connection with the National Curriculum for Key Stage 3 and 4, we can develop ideas and make things happen with Visual Basic as it has a wide range of built-in functions for problem analysis and exchanging and sharing information. It is simple and easy to use thus an extremely an attractive choice for those new to programming. . 4. Bibliography Dfes-A, 2007, Key Concepts in ICT, Department for Children, Schools and Families, The Standards Site, online, http://www.standards.dfes.gov.uk/secondary/keystage3 /subjects/ict/focus/hard_teach_ict/key_cncpts_ict/ Dfes-B, 2007, Principles for Constructing a Scheme of Work, ICT at Key Stages 1 & 2, online,http://www.standards.dfes.gov.uk/schemes2/it/principles?view=get Holzner Steven and Howell Bob, 2002, Ado.Net Programming in Visual Basic .Net, Published 2002 Prentice Hall PTR, ISBN 0131018817 Jones Phil, 2001, Visual Basic: A Complete Course, Published 2001 Thomson Learning EMEA, ISBN 0826454054 Kennewell Steve, 2004, Meeting the Standards in Using ICT for Secondary Teaching, Published 2004 Routledge, ISBN 0415249872 Leask Marilyn and Pachler Norbert, 2005, Learning To Teach Using ICT In The Secondary School: A Companion To School Experience, Published 2005 Routledge, ISBN 0415351049 Naace, 2007, Measuring Success- Implementing ICT, online, http://www.naace.org /impict/ms-monitor.html Patrick Tim, 2006, Visual Basic 2005 Cookbook, Published 2006 O'Reilly, ISBN 0596101775 Perry Greg and Hettihewa Sanjaya, 1998, Sams Teach Yourself Visual Basic 6 in 24 Hours, Published 1998 Sams Publishing, ISBN 0672315335 Read More