In this article, we will learn about the importance of the FocusListener interface in Java. In Java, the FocusListener Interface plays an important role in making GUIs interactive and responsive. It enables the developer to monitor and respond to changes in focus in a Java-based application. FocusListener The focus events are generated whenever a component gains or loses keyboard focus. The Objects representing focus events are created from the FocusEvent Class. The corresponding listener interface for the FocusEvent class is the FocusListener interface. Each listener for FocusEvent can implement the FocusListener interface. Syntax The following is the syntax of the ... Read More

In this article, we will learn to sort the items of a JComboBox in Java. A JComboBox is a basic Swing component, and one of its common requirements is to show the items in sorted order. What is a JComboBox? A JComboBox is a subclass of the JComponent class, and it is a combination of a text field and a drop-down list from which the user can choose a value. A JComboBox can generate the ActionListener, ChangeListener, and ItemListener interfaces when the user actions with a combo box. Syntax The following is the syntax for JComboBox initialization: JComboBox comboBox ... Read More

Let us understand first about regular expressions before jump into I flag. A string of characters that creates a search pattern is called a regular expression. The search pattern can be applied to text replacement and search operations. A regular expression might be a simple pattern with one letter or a more complex one. Text search and replace operations of every kind can be carried out using regular expressions. The literal notation and the constructor are the two methods for creating a RegExp object. The literal notation consists of a pattern among both two slashes and optionally flags beyond ... Read More

Let us understand first about regular expressions before jumping into the /g flag. A string of characters that creates a search pattern is called a regular expression. The search pattern can be applied to text replacement and search operations. A regular expression might be a simple pattern with one letter or a more complex one. Text search and replace operations of every kind can be carried out using regular expressions. The literal notation and the constructor are the two methods for creating a RegExp object. The literal notation consists of a pattern among both two slashes and optionally flags ... Read More

In this article, we will learn to center-align the items of a JComboBox in Java. The default rendering of a JComboBox uses a JLabel for each item. JLabel's default alignment is left-justified, hence the misalignment. JComboBox A JComboBox is a subclass of the JComponent class, and it is a combination of a text field and a drop-down list from which the user can choose a value. A JComboBox can generate an ActionListener, ChangeListener, and an ItemListener when the user actions with a combo box. Center-Align the Items of a JComboBox By default, items in the JCombobox are left-aligned. We ... Read More

In this article, we will learn to display the line numbers inside a JTextArea in Java. When using text editors or code viewers in Java Swing applications, the showing of line numbers can greatly improve the user experience. What is a JTextArea? A JTextArea is a subclass of JTextComponent and it is a multi-line text component to display the text or allow the user to enter a text. A JTextArea can generate a CaretListener interface, which can listen to caret update events. Syntax The following is the syntax for JTextArea initialization: JTextArea textArea = new JTextArea(); By default, JTextArea does ... Read More

In this article, we will learn to align the JRadioButtons horizontally in Java. While designing graphical user interfaces (GUIs) in Java using Swing, you might frequently have to position radio buttons horizontally instead of the default vertical layout. What is a JRadioButton? A JRadioButton is a subclass of JToggleButton and is a two-state button that can be either selected or deselected. Unlike checkboxes, radio buttons are associated with a group, and only one radio button in a group can be selected. This can be implemented using the ButtonGroup class. Syntax The following is the syntax for JButton initialization: JRadioButton ... Read More

In this article, we will learn to add/insert a JCheckBox inside a JTable cell in Java. JTable is a powerful component for displaying and editing data in tables. A frequent requirement is to add checkboxes to table cells for boolean data or selection. JTable A JTable is a subclass of the JComponent class, and it can be used to create a table with information displayed in multiple rows and columns. Syntax The following is the syntax for JTable initialization: JTable table = new JTable(); When a value is selected from a JTable, a TableModelEvent is generated, which is handled by ... Read More

In this article, we will learn about the differences between the TableCellRenderer and TableCellEditor in Java. The JTable interface in Java Swing has these important interfaces called TableCellRenderer and TableCellEditor. Though they serve different purposes, they complement each other in defining the table cells' render and edit functions. TableCellRenderer A TableCellRenderer creates a component that displays the value of a JTable cell. The default renderer uses JLabel to display the value of each table cell. The TableCellRenderer interface can be specified in three ways : By the class of the object to be ... Read More

Javascript window object has provided many methods to get various kinds of information regarding the browser.  It has provided screen.colorDepth and screen.pixelDepth to get the color depth and pixel depth of browser screen respectively. Let's discuss them individually.Color depthThe window object has provided screen.colorDepth method to return the color depth. Color depth is nothing but the number of bits used to display one color. All modern computers use 24 bit or 32 bit hardware for color resolution.ExampleLive Demo document.getElementById("depth").innerHTML = "Screen color depth is " + screen.colorDepth; OutputScreen color depth ... Read More