The classes contained in the java.awt
package provide a basic capability to create graphical user interfaces, but the
scope of the tools contained in java.awt is limited. Furthermore, the actual
implementation of the components is done in a language other than Java, and the
look and behavior of the components is somewhat dependent on the runtime
platform's native environment. AWT components might act slightly differently on
a UNIX system than they would on a PC.
The Swing classes are the next-generation (Java 2) GUI classes. They provide a number of new components including trees, tables, and tooltips, etc. Swing components are written entirely in Java...
Java Swing Interview Questions
The Swing classes are the next-generation (Java 2) GUI classes. They provide a number of new components including trees, tables, and tooltips, etc. Swing components are written entirely in Java...
Java Swing Interview Questions
What
is the difference between Swing and AWT components?
AWT components are
heavy-weight, whereas Swing components are lightweight. Hence Swing works
faster than AWT. Heavy weight components depend on the local windowing toolkit.
For example, java.awt.Button is a heavy weight component. Pluggable look and
feel possible using java Swing. Also, we can switch from one look and feel to
another at runtime in swing which is not possible in AWT.
Name the containers which use Border Layout as their default
layout?
window, Frame and Dialog
classes.
Name Container classes.
Window, Frame, Dialog,
FileDialog, Panel, Applet, or ScrollPane
How can a GUI component handle its own events?
A component can handle
its own events by implementing the required event-listener interface and adding
itself as its own event listener.
What is the difference between the paint() and repaint() methods?
The paint() method
supports painting via a Graphics object. The repaint() method is used to cause
paint() to be invoked by the AWT painting thread.
Which package has light weight components?
javax.Swing package
contains light weight components. All components in Swing, except JApplet,
JDialog, JFrame and JWindow are lightweight components.
What are peerless components?
The peerless components
are called light weight components.
What is a Container in a GUI?
A Container contains and
arranges other components (including other containers) through the use of
layout managers, which use specific layout policies to determine where
components should go as a function of the size of the container.
How are the elements of a GridBagLayout organized?
Or
What is a layout manager and what are different types of layout
managers available in java Swing?
Or
How are the elements of different layouts organized?
A layout manager is an
object that is used to organize components in a container. The different
layouts available are FlowLayout, BorderLayout, CardLayout, GridLayout and
GridBagLayout.
FlowLayout: The elements of a FlowLayout are organized in a top to bottom,
left to right fashion.
BorderLayout: The elements of a BorderLayout are organized at the borders
(North, South, East and West) and the center of a container.
CardLayout: The elements of a CardLayout are stacked, on top of the other,
like a deck of cards.
GridLayout: The elements of a GridLayout are of equal size and are laid out
using the square of a grid.
GridBagLayout: The elements of a GridBagLayout are organized according to a
grid. However, the elements may be different sizes and may occupy more than one
row or column of the grid. In addition, the rows and columns may have different
sizes.
What advantage do Java's layout managers provide over traditional
windowing systems?
Java uses layout
managers to lay out components in a consistent manner across all windowing
platforms. Since Java's layout managers aren't tied to absolute sizing and
positioning, they are able to accommodate platform-specific differences among
windowing systems.
What method is used to specify a container's layout?
The setLayout() method
is used to specify a container's layout. For example, setLayout(new
FlowLayout()); will be set the layout as FlowLayout.
Which Container method is used to cause a container to be laid out
and redisplayed?
validate()
Name Component subclasses that support painting.
The Canvas, Frame,
Panel, and Applet classes support painting.
What is the purpose of the enableEvents() method?
The enableEvents()
method is used to enable an event for a particular component. Normally, an
event is enabled when a listener is added to an object for a particular event.
The enableEvents() method is used by objects that handle events by overriding
their event-dispatch methods.
What is the difference between a Window and a Frame?
The Frame class extends
Window to define a main application window that can have a menu bar.
What do heavy weight components mean?
Heavy weight components
like Abstract Window Toolkit (AWT) depend on the local windowing toolkit. For
example, java.awt .Button is a heavy weight component.
What is the difference
between a Scrollbar and a ScrollPane?
A Scrollbar is just a
Component, but not a Container. A ScrollPane is a Container. A ScrollPane
handles its own events and performs its own scrolling.
What is the preferred size of a component?
The preferred size of a
component is the minimum component size that will allow the component to
display normally.
Which containers use a FlowLayout as their default layout?
The Panel and Applet
classes use the FlowLayout as their default layout.
