Programming Articles - Page 2533 of 3363

The Font class in Java is responsible for setting screen fonts, which are mapped to characters of the language in specific regions. But a FontMetrics class is said to be a font metrics object that encapsulates the data about the rendering of a specific font on a particular screen. Font A Font class can be used to create an instance of a Font object to set the font for drawing text, labels, text fields, buttons, etc, and it can be specified by its name, style, and size. Syntax The following is the syntax for Font initialization: Font font = new ... Read More

In this article, we will learn to set the background color of a JPanel in Java. When designing GUIs in Swing, changing the background color of panels is important for creating visually appealing applications. What is a JPanel? A JPanel is a container, and it is an invisible component in Java. The FlowLayout is a default layout for a JPanel. We can add most of the components, like buttons, text fields, labels, tables, lists, trees, etc., into a JPanel. Syntax The following is the syntax for JPanel initialization: JPanel panel = new JPanel(); Methods The important methods of JPanel are: ... Read More

A JList is a component that can extend JComponent class used to display a list of objects that allows the user to select one or more items.There are three types of selection modes for a JList in JavaListSelectionModel.SINGLE_SELECTION: Only one list index can be selected at a time.ListSelectionModel.SINGLE_INTERVAL_SELECTION: Only one contiguous interval can be selected at a time.ListSelectionModel.MULTIPLE_INTERVAL_SELECTION: In this mode, there is no restriction on what can be selected. This is a default mode.Exampleimport java.awt.*; import java.awt.event.*; import javax.swing.*; public class JListSelectionModeTest extends JFrame implements ActionListener {    private JList list;    private DefaultListModel listModel;    public JListSelectionModeTest() {     ... Read More

The program uses a JLabel to hold a count label, a JTextField component to hold the number count, JButton component to create add, remove and reset buttons. When we click the add button, the count in the JTextField will get incremented by '1' and by clicking the remove button the count will be decremented by '1'. If we click the Reset button, it will reset the count to '0'.Exampleimport java.awt.*; import java.awt.event.*; import javax.swing.*; public class CounterTest extends JFrame implements ActionListener {    private JLabel label;    private JTextField text;    private JButton addBtn, removeBtn, resetBtn;    private int count;    public CounterTest() {       setTitle("Counter Test");   ... Read More

In this article, we will learn to set a border for JCheckBox in Java. JCheckBox is a Swing component that is commonly used in user interface selection. Although it includes a default appearance, we can customize its look by setting borders in order to have a good visual effect. What is a JCheckBox? A JCheckBox is a component that extends JToggleButton, and an object of JCheckBox represents an option that can be checked or unchecked. Syntax The following is the syntax for JCheckBox initialization: JCheckBox Checkbox_name = new JCheckBox(); If there are two or more options, then any ... Read More

A JTextField is a child class of the JTextComponent class through which a single line of text can be edited. Cut, copy, and paste operations of the JTextField component can be implemented using the cut(), copy(), and paste() methods. These are built-in methods in the JTextField class. built-in methodsJTextField class The Cut Operation Cutting involves removing selected text from the JTextField and placing it on the clipboard. Method Declaration: public void cut() { textField.cut(); } The Copy Operation Copying places a copy of the selected text on the clipboard without removing it from the JTextField. Method ... Read More

A simple calculator allows the user to perform basic math operations like addition, subtraction, multiplication, and division . The user inputs two numbers and selects an operation. For example, if the user enters 4 and 3, then selects the "+" operation, the calculator will perform addition and output the result, 7. Similarly, if the user selects "-", the program will perform subtraction (4 - 3 = 1), and so on. In C++, this can be done using conditional statements and basic math operators. In this article, we will show you how to write a simple calculator program in ... Read More

The area of circumcircle of a right-angle triangle when the hypotenuse(H) of the triangle is given is found using the formula πH2/4.This formula is derived using the fact that the circumcircle touches all the corners of the triangle, in this case the maximum length between two points in the hypotheses which passes through the center of the circle. This makes the hypotenuse the diameter of the circle.This is why the area of circle which is πd2/4. (d = 2r) replaces the d by H.ExampleHypotenuse = 8Area of circle = 50.26Example Code Live Demo#include int main(void) {    int H = ... Read More

The area of a circle inscribed inside an equilateral triangle is found using the mathematical formula πa2/12.Lets see how this formula is derived, Formula to find the radius of the inscribed circle = area of the triangle / semi-perimeter of triangle.Area of triangle of side a = (√3)a2/4Semi-perimeter of triangle of side a = 3a/2According to formula, Radius of circle = (√3)a22/4 / 3a/2 = a/2√3Area of circle = πr2 = πa2/12Example Code Live Demo#include int main(void) {    int a = 5;    float pie = 3.14;    float area = (float)((pie*a*a)/12);    printf("the area of circle inscribed in ... Read More

Circle inscribed in a rhombus touches its four side a four ends. The side of rhombus is a tangent to the circle.Here, r is the radius that is to be found using a and, the diagonals whose values are given.Now the area of triangle AOB = ½ * OA * OB = ½ * AB * r (both using formula ½*b*h).½ *a/2*b/2 = ½ *( √ (a2/4 + b2/4))*ra*b/8 = √ (a2+ b2 )*r /4r = a*b/ 2√ (a2+ b2 )Area of circle = π*r*r = π*(a2*b2)/4(a2+ b2 )ExampleThe diagonal of the rhombus 5 & 10.Area is 15.700000Example Code Live Demo#include ... Read More