Я только что сделал это недавно - я хотел иметь возможность объединить несколько значков в одном ряду в один значок.Я сделал так, чтобы спуститься до уровня BufferedImage
и скомпоновать два изображения вручную в одно изображение, а затем использовать его в качестве моего значка JLabel
.Существуют и другие способы достижения того же эффекта, но я не хотел менять иерархию компонентов пользовательского интерфейса.
В итоге я создал класс, который объединяет несколько изображений и кэширует их.Я использовал это так:
ImageIcon icon1 = ...;
ImageIcon icon2 = ...;
ImageIcon labelIcon = new CachedCompositeIcon( icon1, icon2 ).getIcon();
jLabel.setIcon( labelIcon );
Вот источник:
/** This is a convenience class to handle creating a single composite icon from several icons, and caching the
* created icons to eliminate duplicate work. This class is basically used as a key into a map, allowing us to
* define both a hashCode and equals in a single place.
*/
public class CachedCompositeIcon
{
private static final byte ICON_PADDING = 2;
private static final HashMap<CachedCompositeIcon, ImageIcon> CACHED_ICONS =
new HashMap<CachedCompositeIcon, ImageIcon>( 4 );
private final ImageIcon[] m_icons;
public CachedCompositeIcon(final ImageIcon... icons) {
m_icons = icons;
}
public ImageIcon getIcon() {
if ( !CACHED_ICONS.containsKey( this ) ) {
CACHED_ICONS.put( this, lcl_combineIcons() );
}
return CACHED_ICONS.get( this );
}
/** Generates an icon that is a composition of several icons by appending each icon together with some
* padding between them.
*
* @return An icon that is the concatenation of all the icons this was constructed with.
*/
private ImageIcon lcl_combineIcons() {
// First determine how big our composite icon will be; we need to know how wide & tall to make it.
int totalWidth = (m_icons.length - 1) * ICON_PADDING; // Take into account the padding between icons
int minHeight = 0;
for ( int i = 0; i < m_icons.length; ++i ) {
totalWidth += m_icons[i].getIconWidth();
if ( m_icons[i].getIconHeight() > minHeight ) {
minHeight = m_icons[i].getIconHeight();
}
}
// Create an image big enough and acquire the image canvas to draw on
final BufferedImage compositeImage = new BufferedImage( totalWidth, minHeight, BufferedImage.TYPE_INT_ARGB );
final Graphics graphics = compositeImage.createGraphics();
// Iterate over the icons, painting each icon and adding some padding space between them
int x = 0;
for ( int i = 0; i < m_icons.length; ++i ) {
final ImageIcon icon = m_icons[ i ];
graphics.drawImage( icon.getImage(), x, 0, null );
x += icon.getIconWidth() + ICON_PADDING;
}
return new ImageIcon( compositeImage );
}
/** Generates a hash that takes into account the number of icons this composition includes and the hash &
* order of those icons.
*
* @return A hash code.
*/
@Override
public int hashCode() {
int weakHash = m_icons.length;
for ( int i = 0; i < m_icons.length; ++i ) {
weakHash += m_icons[i].hashCode() * (i + 1);
}
return weakHash;
}
/** Two instances are equal if and only if they include the same icons and they're in the same order.
*
* @param obj An object to check for equality with this.
*
* @return true if the two objects are equal, false otherwise.
*/
@Override
public boolean equals(final Object obj) {
if ( !(obj instanceof CachedCompositeIcon) ) {
return false;
}
final CachedCompositeIcon other = (CachedCompositeIcon) obj;
if ( m_icons.length != other.m_icons.length ) {
return false;
}
for ( int i = 0; i < m_icons.length; ++i ) {
if ( m_icons[i].hashCode() != other.m_icons[i].hashCode() ) {
return false;
}
}
return true;
}
}