Designing a Visual Application and Using its Features - Assignment Example

Designing a Visual Application and using its features Written by ; Maintained by Harvard - 1. Introduction The purpose of this assignment is to demonstrate an ability to use visual objects, design a visual application, and use advanced features of the visual development environment to implement an application. A Visual Basic front end of the Students.mdb database is created for the use of Student administration. The tasks for the assignment are first deciding the front end by drawing the structure and state transition diagram, then designing the front end and showing the use of data types, arrays and selection structures if any, and finally documenting and analyzing how the current application design was organized and managed to achieve the final report. 2. Planning the application This application is to be used by the college Student administration. The current application used by the college does not offer much efficiency for data input, update and deletion. It is also prone to error during data entry. The student information such as ID, name, marks, assignment, communication skills, etc should offer ease of use. Planning needs to done for searching with reference to any attribute specified on the form for retrieving any required information. It should also take into account the data input errors when any data is added or updated to the student database. The students are given various assignments on the basis of which they are evaluated, and the student administrator adds their marks to student database for reference. This database should also be used to retrieve the said information when required. The improved application aims to resolve these issues by offering more user-friendly navigation and forms. It also aims to provide easier information access and reduced level of data input. 3. The application structure and state transition diagram The application structure can be arranged as entities and actions with their associated constructs. The entities are unique and capable of performing actions. An attribute is a variable of the entity. 3.1 The Student entity and action structure diagram. The structure diagram of the proposed Student Administration application has been modeled taking the various entities involved and the actions carried out on these entities. The choices made by the user for effecting the changes have also been stated. The event table describes the external events that trigger an action by the sources on the system, as per the structure diagram. Event Trigger Source Activity Response Destination Student Administrator Add a new record of student information. Student, Lecturer Add a new record to the student database View the updated record Student, Lecturer Student Administrator Delete any recorded of the student information. Student, Lecturer Delete the record from the student database View the updated record Student, Lecturer Student Administrator Update an existing record in student information. Student, Lecturer Update an existing record in the student database View the updated record Student, Lecturer Student Administrator View the list of required records. Student, Lecturer Retrieve the relevant records from the student database View the updated record Student, Lecturer The following are the list of entities, attributes, and actions of the system: Entities Student: The Student is the primary entity of the system. The actions are performed on attributes of the entity. Communication Skills: This entity denotes the communications skills of the student. Marks: This entity denotes the marks scored by the student. Assignment: This entity denotes the assignments given to the student for which he is evaluated. Action Add: The new record is added to the student database. Update: The existing records are updated in the student database. Delete: The records are deleted from the student database. Get Information: The required records are retrieved from the student database and viewed. Attributes Student_id: The unique identification number of the student Student_firstname: The students first name Student_lastname: The students last name Mark_id: The unique identification number indicating the mark rating Pass_status: The passing status or rating of the student Assignment_id: The unique identification number indicating the assignment Assignment_name: The assignment name Commonskills_id: The unique identification used to indicate the assignments related to communication skills CommSkills: The assignments given for communication skills A network of processes connected by Datastreams and State Vector Inspection connections can represent the process flow in the system. This is displayed in the State Transition Diagram Where the 3.2 The Entity-relationship diagram The entity relationship diagram gives the relationship between the various entities of the system. The various entities such as Marks, Assignment, and Communication Skills are related to the primary entity Student. ______|__ | ` 3.2.1 Table details Table name: Students Description: This table is used to store all the student information. FIELD NAME CONSTRAINT TYPE DESCRIPTION Student_id Primary key Long Integer The value is auto-generated and can have no duplicates. Student_firstname Char (50) The value is mandatory and can have duplicates. Student_lastname Char (50) The value is mandatory and can have duplicates. Table name: Marks Description: This table is used to store the students marks. FIELD NAME CONSTRAINT TYPE DESCRIPTION Marks_id Primary key Long Integer The value is auto-generated and can have no duplicates. Pass_status Char (50) The value is mandatory and can have duplicates. Student_id Foreign Key Long Integer The foreign key references Students and value can have duplicates. Table name: Assignment Description: This table is used to store the assignment details. FIELD NAME CONSTRAINT TYPE DESCRIPTION Assignment_id Primary key Long Integer The value is auto-generated and can have no duplicates. Assignment_name Char (50) The value is mandatory and can have duplicates. Student_id Foreign Key Long Integer The foreign key references Students and value can have duplicates. Table name: CSkills Description: This table is used to store the communication skills assignment details. FIELD NAME CONSTRAINT TYPE DESCRIPTION Commonskills_id Primary key Varchar (50) The value can be both numerals and letters and can have no duplicates. CommSkills Char (50) The value is mandatory and can have duplicates. Student_id Foreign Key Long Integer The foreign key references Students and value can have duplicates. 3.3 The Multiple form menu tree The forms in the application have been designed based on the flow of process and requirements as displayed in the structure and state transition diagrams. The entity relationships are taken into account for programming the actions performed on the entities and their attributes. The main form has two menus View Details and Modify. All the subsequent forms are loaded on the main form. Student Administration 3.3.1 Form details The application has been designed with a multiple forms. The information regarding the forms used, are given below: FORM NAME CAPTION DESCRIPTION frmmenu_studadmin Student Administration This is the first form of the application. It has the menus View Details and Modify frmsearch Search Takes the information from the user and searches the database to display a report in the View Details form frm_viewdetails View Details Displays the records as per the search information given by the user in the Search form. The details can be closed to return to the Student Administration form. frmchoose_modify Choose the modification Takes the user inputs on the type of modification, whether it’s for adding new records, updating, or deleting. It then takes user inputs to modify the required field attributes. Finally, it displays the modified records. 4. Programming the application The Visual basic application consists of the main form named Student Administration, which has the menu bar giving the selections View Details and Modify. The user chooses his required option. In case the chosen option is View Details then this takes the user to the form Search. The Search form allows us to select the criteria for searching the required details. In this form the functionality can be described with these steps: 1. Select the search criteria from the options given i.e. Student, Assignment, Marks, and Communication Skills. On selection of the option, the categories of information that can be given are enabled on the form. This can be done by using this code: If CheckStudent.Checked = True Then frmstudmin.lblstudFirstname.Visible = True frmstudmin.txtstudFirstname.Visible = True frmstudmin.lblstudid.Visible = True frmstudmin.txtstudid.Visible = True frmstudmin.lblstudname.Enabled = True frmstudmin.txtstudname.Enabled = True frmstudmin.lblstudid.Enabled = True frmstudmin.txtstudid.Enabled = True Else …. (The same code repeated as per the checkbox selections for Assignment, Marks, and Communication Skills.) 2. During the data inputs, the text typed in can be checked for errors. The text can be checked for the right data type for example, if its an integer or character value. This can be done using this code: First the required data types are defined in the form at the Form_load() : Dim rs As New ADODB.Recordset Public studFirstname as String Public studid as Integer Then, type: If studFirstname.Text = "" And studid.Text = "" Then MsgBox ("Please fill in at least one information") End If And, for checking the right data types are inserted in Private Sub studFirstname_KeyPress, type: If KeyAscii >= vbKeyA And KeyAscii Read More