BD Computer Technology - Java Programming: SWING

java.lang.Object
 └java.awt.Component
     └java.awt.Container
         └javax.swing.JComponent
             └javax.swing.JLabel

Constructor Summary
`JLabel()` Creates a `JLabel` instance with no image and with an empty string for the title.
`JLabel(Icon image)` Creates a `JLabel` instance with the specified image.
`JLabel(Icon image, int horizontalAlignment)` Creates a `JLabel` instance with the specified image and horizontal alignment.
`JLabel(String text)` Creates a `JLabel` instance with the specified text.
`JLabel(String text, Icon icon, int horizontalAlignment)` Creates a `JLabel` instance with the specified text, image, and horizontal alignment.
`JLabel(String text, int horizontalAlignment)` Creates a `JLabel` instance with the specified text and horizontal alignment.

Method Summary
`protected int`	`checkHorizontalKey(int key, String message)` Verify that key is a legal value for the horizontalAlignment properties.
`protected int`	`checkVerticalKey(int key, String message)` Verify that key is a legal value for the verticalAlignment or verticalTextPosition properties.
`AccessibleContext`	`getAccessibleContext()` Get the AccessibleContext of this object
`Icon`	`getDisabledIcon()` Returns the value of the disabledIcon property if it's been set, If it hasn't been set and the value of the icon property is an ImageIcon, we compute a "grayed out" version of the icon and update the disabledIcon property with that.
`int`	`getDisplayedMnemonic()` Return the keycode that indicates a mnemonic key.
`int`	`getDisplayedMnemonicIndex()` Returns the character, as an index, that the look and feel should provide decoration for as representing the mnemonic character.
`int`	`getHorizontalAlignment()` Returns the alignment of the label's contents along the X axis.
`int`	`getHorizontalTextPosition()` Returns the horizontal position of the label's text, relative to its image.
`Icon`	`getIcon()` Returns the graphic image (glyph, icon) that the label displays.
`int`	`getIconTextGap()` Returns the amount of space between the text and the icon displayed in this label.
`Component`	`getLabelFor()` Get the component this is labelling.
`String`	`getText()` Returns the text string that the label displays.
`LabelUI`	`getUI()` Returns the L&F object that renders this component.
`String`	`getUIClassID()` Returns a string that specifies the name of the l&f class that renders this component.
`int`	`getVerticalAlignment()` Returns the alignment of the label's contents along the Y axis.
`int`	`getVerticalTextPosition()` Returns the vertical position of the label's text, relative to its image.
`boolean`	`imageUpdate(Image img, int infoflags, int x, int y, int w, int h)` This is overridden to return false if the current Icon's Image is not equal to the passed in Image `img`.
`protected String`	`paramString()` Returns a string representation of this JLabel.
`void`	`setDisabledIcon(Icon disabledIcon)` Set the icon to be displayed if this JLabel is "disabled" (JLabel.setEnabled(false)).
`void`	`setDisplayedMnemonic(char aChar)` Specifies the displayedMnemonic as a char value.
`void`	`setDisplayedMnemonic(int key)` Specify a keycode that indicates a mnemonic key.
`void`	`setDisplayedMnemonicIndex(int index)` Provides a hint to the look and feel as to which character in the text should be decorated to represent the mnemonic.
`void`	`setHorizontalAlignment(int alignment)` Sets the alignment of the label's contents along the X axis.
`void`	`setHorizontalTextPosition(int textPosition)` Sets the horizontal position of the label's text, relative to its image.
`void`	`setIcon(Icon icon)` Defines the icon this component will display.
`void`	`setIconTextGap(int iconTextGap)` If both the icon and text properties are set, this property defines the space between them.
`void`	`setLabelFor(Component c)` Set the component this is labelling.
`void`	`setText(String text)` Defines the single line of text this component will display.
`void`	`setUI(LabelUI ui)` Sets the L&F object that renders this component.
`void`	`setVerticalAlignment(int alignment)` Sets the alignment of the label's contents along the Y axis.
`void`	`setVerticalTextPosition(int textPosition)` Sets the vertical position of the label's text, relative to its image.
`void`	`updateUI()` Resets the UI property to a value from the current look and feel.

Example:

import java.awt.*;
import javax.swing.*;

public class jlabel extends JApplet{
public jlabel() {
Container contentpane=getContentPane();
JLabel label=new JLabel("Hello from Java");
contentpane.setLayout(new FlowLayout()); //Used for Line Alignment
contentpane.add(label);
}
}

The ImageIcon class lets you create an icon from an image file for use in a Swing control.

Constructor Summary
`ImageIcon()` Creates an uninitialized image icon.
`ImageIcon(byte[] imageData)` Creates an ImageIcon from an array of bytes which were read from an image file containing a supported image format, such as GIF or JPEG.
`ImageIcon(byte[] imageData, String description)` Creates an ImageIcon from an array of bytes which were read from an image file containing a supported image format, such as GIF or JPEG.
`ImageIcon(Image image)` Creates an ImageIcon from an image object.
`ImageIcon(Image image, String description)` Creates an ImageIcon from the image.
`ImageIcon(String filename)` Creates an ImageIcon from the specified file.
`ImageIcon(String filename, String description)` Creates an ImageIcon from the specified file.
`ImageIcon(URL location)` Creates an ImageIcon from the specified URL.
`ImageIcon(URL location, String description)` Creates an ImageIcon from the specified URL.

Method Summary
`AccessibleContext`	`getAccessibleContext()` Gets the AccessibleContext associated with this ImageIcon.
`String`	`getDescription()` Gets the description of the image.
`int`	`getIconHeight()` Gets the height of the icon.
`int`	`getIconWidth()` Gets the width of the icon.
`Image`	`getImage()` Returns this icon's `Image`.
`int`	`getImageLoadStatus()` Returns the status of the image loading operation.
`ImageObserver`	`getImageObserver()` Returns the image observer for the image.
`protected void`	`loadImage(Image image)` Loads the image, returning only when the image is loaded.
`void`	`paintIcon(Component c, Graphics g, int x, int y)` Paints the icon.
`void`	`setDescription(String description)` Sets the description of the image.
`void`	`setImage(Image image)` Sets the image displayed by this icon.
`void`	`setImageObserver(ImageObserver observer)` Sets the image observer for the image.
`String`	`toString()` Returns a string representation of this image.

Example:

import java.awt.*;
import javax.swing.*;

public class jlabel extends JApplet{

public void jlabel() {
Container contentPane=getContentPane();

JLabel label=new JLabel("Label", new ImageIcon("label.jpg"), JLabel.CENTER);
label.setVerticalTextPosition(JLabel.BOTTOM);
label.setHorizontalTextPosition(JLabel.CENTER);

contentPane.add(label);
}

SWING - Label