LAB ACTIVITY 1B

Learning Outcomes

By the end of this lab, students should be able to :

• Use AWT in Java programs

• Create and set the Frame Windows

• Create various AWT components

Hardware/ Software : Personal Computer, Java Development Kit version 1.8.x., JCreator IDE, MS-DOS

Step 1: Create a Java Project/Class

1. Open Your IDE: Start your Integrated Development Environment (IDE) like Eclipse, NetBeans, or IntelliJ IDEA.

2. Create a New Project:

   • In your IDE, select File > New > Project.

   • Choose Java Project and click Next.

   • Name your project ("LabActivity_1") and click Finish.

3. Create a New Class:

   • Right-click on the src folder in your project and select New > Class.

   • Name your class ( "LabActivity_1B") and check the box to include the main method.

   • Click Finish.

Step 2: Setting the Frame Properties

1. Import AWT Packages: At the top of your class, import the necessary AWT packages.

2. Class Declaration

• public class LabActivity_1B extends Frame:

  • This declares a public class named LabActivity_1B that extends the Frame class.

3. Constructor

• Constructor Declaration: LabActivity_1B() is the constructor of the class. It is automatically called when an instance of LabActivity_1B is created.

4. Setting the Frame Title

• setTitle("Payroll System");:

  • The title appears in the title bar of the window, helping users identify the purpose of the window.

5. Setting the Layout Manager

• setLayout(new FlowLayout(FlowLayout.LEFT));:

  • This line sets the layout manager for the frame to FlowLayout.

  • FlowLayout: This layout manager arranges components in a left-to-right flow, much like lines of text in a paragraph. If there isn't enough room to fit all components on one line, FlowLayout moves to the next line.

  • FlowLayout.LEFT: This argument specifies that the components should be aligned to the left side of the container.

6. Setting the Frame Size

• setSize(280, 450);:

  • This line sets the width and height of the frame.

  • Width = 280 pixels: The width of the window is set to 280 pixels.

  • Height = 450 pixels: The height of the window is set to 450 pixels.

7. Making the Frame Visible

• setVisible(true);:

  • This line makes the frame visible on the screen.

  • By default, frames are invisible when created. You need to set them visible by calling setVisible(true).

8. Main Method: The main method creates an instance of LabActivity_1B, which triggers the constructor and and initializes the graphical user interface (GUI) 

Step 4: Declare all the components. 

Component Declaration

• Labels: Labels are declared to display static text like "ID", "Name", "Gender", etc.

Label lblTitle, lblid, lblnama, lbljantina, lbldept;

Label lblbasic, lblelaun1, lbljamOt, lblot, lbltotal, lbldeduct;

• TextFields: Text fields are declared for user input such as ID, Name, Basic Salary, etc.

TextField txtId, txtNama, txtJantina, txtJabatan;

TextField txtbasic, txtelaun1, txtjamOt, txtot, txttotal, txtdeduct;

• CheckboxGroup and Checkboxes: A CheckboxGroup is declared to group radio buttons, allowing the selection of either "Male" or "Female". The checkboxes themselves are declared as well.

Checkbox cbLelaki, cbPerempuan;

CheckboxGroup cbg;

• Choice: A Choice component is declared for the department selection dropdown menu.

Choice cjabatan;

• Buttons: Buttons are declared for actions such as "Calculate," "Clear," and "Display".

Button btnCalc, btnClear, btnDisplay;

• Panels: Panels are declared to group related components together.

Panel panel1, panel2;

• TextArea: A TextArea is declared to display multi-line output text.

TextArea txtdisplay = new TextArea(3, 30);

• Variables for Calculations: Double variables are declared to hold numerical values used in calculations.

Double basic, allowance, jamot, totalot, totalsalary, deduct;

Step 4: Component Declaration

• Labels: Several Label components are declared to display text in the GUI.

• TextField: A TextField is declared to allow the user to input text.

• CheckboxGroup and Checkboxes: CheckboxGroup is used to group checkboxes, allowing only one checkbox in the group to be selected at a time (like radio buttons). Individual checkboxes are declared for gender selection and course selection.

• List: A List component is declared to allow the selection of multiple items from a list of departments.

• Choice: A Choice component is declared, which is a dropdown menu for selecting a class.

• Buttons: Button components are declared for user actions such as "Submit" and "Clear".

• TextArea: A TextArea is declared to display multi-line text output.

Step 5: Constructor Initialization

• Font Setup: Two Font objects (f1 and f2) are created for setting the font style and size for different labels.

• Label Initialization: Labels like lblTitle, lblName, and others are initialized with descriptive text. The lblTitle is also customized with a font and color.

• TextField Initialization: The TextField txtName is initialized with a width of 20 characters.

• Choice Initialization: The Choice component cClass is initialized with several options like "DDT5A", "DDT5B", and "DDT5C".

• Checkbox and CheckboxGroup Initialization: The gender selection checkboxes (rbMale, rbFemale) are grouped into cgGender, ensuring that only one gender can be selected at a time. Course selection checkboxes (cbCo1, cbCo2, etc.) are also initialized.

• List Initialization: The List component lsDept is initialized with department options like "JTMK", "JKM", "JKE", and "JP".

• Button Initialization: The buttons btnSubmit and btnClear are initialized with the text "SUBMIT" and "CLEAR", respectively.

• TextArea Initialization: The TextArea txtDisplay is initialized with 5 rows and 30 columns.

Step 6: Adding Components to Frame

• Each component is added to the frame using the add() method. For example, add(lblTitle); adds the title label to the frame.