When created, the window is given a default height and width. This causes a frame window to come into existence, but it will not be initially visible. Once you have defined a Frame subclass, you can create an object of that class inside the
SetVisible(false) to get the window closed when the close button(X) is pressed. Implement the windowClosing( ) method of the WindowListener interface, by calling the WeĬan also add the required event listeners to these components for event handling. Use the constructor to add necessary components in the required layout into the frame. This allows us to override Frame’s methods and provide event handling. Process events that occur within it or easily output information to it. For example, you will not be able to receive or While it is possible to simply create a window by creating an instance of Frame, you will seldomĭo so, because you will not be able to do much with it.
#FLOWLAYOUT IN JAVA SWING WINDOWS#
Window or windows (Frames) you need inside main( ). To do this, simply create an instance of the Possible to create stand-alone AWT-based applications. Inside windowClosing( ), youĬreating a Windowed Program : Although creating applets is a common use for Java’s AWT, it is also Implement the windowClosing( ) method of the WindowListener interface. To intercept a window-close event, you must The screen when it is closed, by calling setVisible(false). Here, newTitle is the new title for the window.Ĭlosing a Frame Window : When using a frame window, your program must remove that window from You can change the title in a frame window using setTitle( ), which has this general form: The component is visible if the argument to this method is true. SetLocation(), setSize( ), setPreferredSize( ), or setBounds( ) methods defined by Component.
Once these components have been added, you can position and resize them manually using the Other components can be added to a Panel object by its add( ) method(inherited from Container). When you run an applet using an applet viewer, the applet viewer provides the title This is why you don’t see these items when an applet is In essence, a Panel is a window thatĭoes not contain a title bar, menu bar, or border. When screen output isĭirected to an applet, it is drawn on the surface of a Panel object. A Panel may be thought of as a recursively The Panel class is a concrete subclass of Container.
Through the use of various layout managers. This makes for a multileveled containment system.Ī container is responsible for laying out (that is, positioning) any components that it contains. (since they are themselves instances of Component). Other Container objects can be stored inside of a Container It has additional methods that allow otherĬomponent objects to be nested within it. The Container class is a subclass of Component. A Component object is responsible for remembering the currentįoreground and background colors and the currently selected text font. Public methods that are responsible for managing events, such as mouse and keyboard input, positioningĪnd sizing the window, repainting etc. The screen and that interact with the user are subclasses of Component. All user interface elements that are displayed on Component is an abstract class thatĮncapsulates all of the attributes of a visual component. Much of the functionality of these windows is derived from their parent classes.įigure shows the class hierarchy for Panel and Frame.Īt the top of the AWT hierarchy is the Component class. Those derived from Frame (used to create standard application windows). Those derived from Panel ( used by applets)Ģ. Various output methods to display output in a window.ġ. Graphics Encapsulates the graphics context. MenuShortcut Encapsulates a keyboard shortcut for a menu item.įileDialog Creates a window from which a file can be selected. MenuComponent An abstract class implemented by various menu classes. Border layouts use fiveĬomponents: North, South, East, West, and Center. Flow layout positions componentsīorderLayout The border layout manager. ScrollPane A container that provides horizontal and/or vertical scroll barsįlowLayout The flow layout manager. Window Creates a window with no frame, no menu bar, and no title. Panel The simplest concrete subclass of Container.įrame Creates a standard window that has a title bar, resize corners, TextArea Creates a multiline edit control. Similar to theĬheckboxGroup Creates a group of check box controls.ĬheckboxMenuItem Creates an on/off menu item. List Creates a list from which the user can choose. TextField Creates a single-line edit control. Label Creates a label that displays a string. It is one of Java’s largest packages.įortunately, it is easier to understand and use, because it is logically organized in a top-down, The AWT classes are contained in the java package. Working with Windows and AWT (AWT Classes)
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