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Diffstat (limited to 'libjava/classpath/javax/swing/JLabel.java')
| -rw-r--r-- | libjava/classpath/javax/swing/JLabel.java | 647 |
1 files changed, 647 insertions, 0 deletions
diff --git a/libjava/classpath/javax/swing/JLabel.java b/libjava/classpath/javax/swing/JLabel.java new file mode 100644 index 0000000..088f7d6 --- /dev/null +++ b/libjava/classpath/javax/swing/JLabel.java @@ -0,0 +1,647 @@ +/* JLabel.java -- + Copyright (C) 2002, 2004, 2005 Free Software Foundation, Inc. + +This file is part of GNU Classpath. + +GNU Classpath is free software; you can redistribute it and/or modify +it under the terms of the GNU General Public License as published by +the Free Software Foundation; either version 2, or (at your option) +any later version. + +GNU Classpath is distributed in the hope that it will be useful, but +WITHOUT ANY WARRANTY; without even the implied warranty of +MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU +General Public License for more details. + +You should have received a copy of the GNU General Public License +along with GNU Classpath; see the file COPYING. If not, write to the +Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA +02110-1301 USA. + +Linking this library statically or dynamically with other modules is +making a combined work based on this library. Thus, the terms and +conditions of the GNU General Public License cover the whole +combination. + +As a special exception, the copyright holders of this library give you +permission to link this library with independent modules to produce an +executable, regardless of the license terms of these independent +modules, and to copy and distribute the resulting executable under +terms of your choice, provided that you also meet, for each linked +independent module, the terms and conditions of the license of that +module. An independent module is a module which is not derived from +or based on this library. If you modify this library, you may extend +this exception to your version of the library, but you are not +obligated to do so. If you do not wish to do so, delete this +exception statement from your version. */ + + +package javax.swing; + +import java.awt.Component; +import java.awt.Font; +import java.awt.Image; +import java.awt.event.KeyEvent; + +import javax.accessibility.Accessible; +import javax.accessibility.AccessibleContext; +import javax.swing.plaf.LabelUI; + +/** + * A swing widget that displays a text message and/or an icon. + */ +public class JLabel extends JComponent implements Accessible, SwingConstants +{ + /** DOCUMENT ME! */ + private static final long serialVersionUID = 5496508283662221534L; + + /** + * The Component the label will give focus to when its mnemonic is + * activated. + */ + protected Component labelFor; + + /** The label's text. */ + private transient String text; + + /** Where the label will be positioned horizontally. */ + private transient int horizontalAlignment = LEADING; + + /** Where the label text will be placed horizontally relative to the icon. */ + private transient int horizontalTextPosition = TRAILING; + + /** Where the label will be positioned vertically. */ + private transient int verticalAlignment = CENTER; + + /** Where the label text will be place vertically relative to the icon. */ + private transient int verticalTextPosition = CENTER; + + /** The icon painted when the label is enabled. */ + private transient Icon icon; + + /** The icon painted when the label is disabled. */ + private transient Icon disabledIcon; + + /** The label's mnemnonic key. */ + private transient int displayedMnemonic = KeyEvent.VK_UNDEFINED; + + /** The index of the menemonic character in the text. */ + private transient int displayedMnemonicIndex = -1; + + /** The gap between the icon and the text. */ + private transient int iconTextGap = 4; + + /** + * Creates a new vertically centered, horizontally on the leading edge + * JLabel object with text and no icon. + */ + public JLabel() + { + this(null, null, LEADING); + } + + /** + * Creates a new vertically and horizontally centered + * JLabel object with no text and the given icon. + * + * @param image The icon to use with the label. + */ + public JLabel(Icon image) + { + this(null, image, CENTER); + } + + /** + * Creates a new vertically centered JLabel object with no text and the + * given icon and horizontal alignment. By default, the text is TRAILING + * the image. + * + * @param image The icon to use with the label. + * @param horizontalAlignment The horizontal alignment of the label. + */ + public JLabel(Icon image, int horizontalAlignment) + { + this(null, image, horizontalAlignment); + } + + /** + * Creates a new horizontally leading and vertically centered JLabel + * object with no icon and the given text. + * + * @param text The text to use with the label. + */ + public JLabel(String text) + { + this(text, null, LEADING); + } + + /** + * Creates a new vertically centered JLabel object with no icon and the + * given text and horizontal alignment. + * + * @param text The text to use with the label. + * @param horizontalAlignment The horizontal alignment of the label. + */ + public JLabel(String text, int horizontalAlignment) + { + this(text, null, horizontalAlignment); + } + + /** + * Creates a new vertically centered JLabel object with the given text, + * icon, and horizontal alignment. + * + * @param text The text to use with the label. + * @param icon The icon to use with the label. + * @param horizontalAlignment The horizontal alignment of the label. + */ + public JLabel(String text, Icon icon, int horizontalAlignment) + { + this.text = text; + this.icon = icon; + this.horizontalAlignment = horizontalAlignment; + updateUI(); + } + + /** + * This method returns the label's UI delegate. + * + * @return The label's UI delegate. + */ + public LabelUI getUI() + { + return (LabelUI) ui; + } + + /** + * This method sets the label's UI delegate. + * + * @param ui The label's UI delegate. + */ + public void setUI(LabelUI ui) + { + super.setUI(ui); + } + + /** + * This method resets the label's UI delegate to the default UI for the + * current look and feel. + */ + public void updateUI() + { + setUI((LabelUI) UIManager.getUI(this)); + } + + /** + * This method returns a name to identify which look and feel class will be + * the UI delegate for this label. + * + * @return The UIClass identifier. "LabelUI" + */ + public String getUIClassID() + { + return "LabelUI"; + } + + /** + * This method is used primarily for debugging purposes and returns a string + * that can be used to represent this label. + * + * @return A string to represent this label. + */ + protected String paramString() + { + return "JLabel"; + } + + /** + * This method returns the label text. + * + * @return The label text. + */ + public String getText() + { + return text; + } + + /** + * This method changes the "text" property. The given text will be painted + * in the label. + * + * @param newText The label's text. + */ + public void setText(String newText) + { + if (text != newText) + { + String oldText = text; + text = newText; + firePropertyChange("text", oldText, newText); + + if (text != null && text.length() <= displayedMnemonicIndex) + setDisplayedMnemonicIndex(text.length() - 1); + } + } + + /** + * This method returns the active icon. The active icon is painted when the + * label is enabled. + * + * @return The active icon. + */ + public Icon getIcon() + { + return icon; + } + + /** + * This method changes the "icon" property. This icon (the active icon) will + * be the one displayed when the label is enabled. + * + * @param newIcon The active icon. + */ + public void setIcon(Icon newIcon) + { + if (icon != newIcon) + { + Icon oldIcon = icon; + icon = newIcon; + firePropertyChange("icon", oldIcon, newIcon); + } + } + + /** + * This method returns the disabled icon. The disabled icon is painted when + * the label is disabled. If the disabled icon is null and the active icon + * is an ImageIcon, this method returns a grayed version of the icon. The + * grayed version of the icon becomes the disabledIcon. + * + * @return The disabled icon. + */ + public Icon getDisabledIcon() + { + if (disabledIcon == null && icon instanceof ImageIcon) + disabledIcon = new ImageIcon(GrayFilter.createDisabledImage(((ImageIcon) icon) + .getImage())); + + return disabledIcon; + } + + /** + * This method changes the "disabledIcon" property. This icon (the disabled + * icon) will be the one displayed when the label is disabled. + * + * @param newIcon The disabled icon. + */ + public void setDisabledIcon(Icon newIcon) + { + if (disabledIcon != newIcon) + { + Icon oldIcon = disabledIcon; + disabledIcon = newIcon; + firePropertyChange("disabledIcon", oldIcon, newIcon); + } + } + + /** + * This method sets the keycode that will be the label's mnemonic. If the + * label is used as a label for another component, the label will give + * focus to that component when the mnemonic is activated. + * + * @param mnemonic The keycode to use for the mnemonic. + */ + public void setDisplayedMnemonic(int mnemonic) + { + if (displayedMnemonic != mnemonic) + { + firePropertyChange("displayedMnemonic", + displayedMnemonic, mnemonic); + displayedMnemonic = mnemonic; + + if (text != null) + setDisplayedMnemonicIndex(text.toUpperCase().indexOf(mnemonic)); + } + } + + /** + * This method sets the character that will be the mnemonic used. If the + * label is used as a label for another component, the label will give + * focus to that component when the mnemonic is activated. + * + * @param mnemonic The character to use for the mnemonic. + */ + public void setDisplayedMnemonic(char mnemonic) + { + setDisplayedMnemonic((int) Character.toUpperCase(mnemonic)); + } + + /** + * This method returns the keycode that is used for the label's mnemonic. + * + * @return The keycode that is used for the label's mnemonic. + */ + public int getDisplayedMnemonic() + { + return (int) displayedMnemonic; + } + + /** + * This method sets which character in the text will be the underlined + * character. If the given index is -1, then this indicates that there is + * no mnemonic. If the index is less than -1 or if the index is equal to + * the length, this method will throw an IllegalArgumentException. + * + * @param newIndex The index of the character to underline. + * + * @throws IllegalArgumentException If index less than -1 or index equals + * length. + */ + public void setDisplayedMnemonicIndex(int newIndex) + throws IllegalArgumentException + { + if (newIndex < -1 || (text != null && newIndex >= text.length())) + throw new IllegalArgumentException(); + + if (newIndex == -1 + || text == null + || text.charAt(newIndex) != displayedMnemonic) + newIndex = -1; + + if (newIndex != displayedMnemonicIndex) + { + int oldIndex = displayedMnemonicIndex; + displayedMnemonicIndex = newIndex; + firePropertyChange("displayedMnemonicIndex", + oldIndex, newIndex); + } + } + + /** + * This method returns which character in the text will be the underlined + * character. + * + * @return The index of the character that will be underlined. + */ + public int getDisplayedMnemonicIndex() + { + return displayedMnemonicIndex; + } + + /** + * This method ensures that the key is valid as a horizontal alignment. + * Valid keys are: LEFT, CENTER, RIGHT, LEADING, TRAILING + * + * @param key The key to check. + * @param message The message of the exception to be thrown if the key is + * invalid. + * + * @return The key if it's valid. + * + * @throws IllegalArgumentException If the key is invalid. + */ + protected int checkHorizontalKey(int key, String message) + { + if (key != LEFT && key != CENTER && key != RIGHT && key != LEADING + && key != TRAILING) + throw new IllegalArgumentException(message); + else + return key; + } + + /** + * This method ensures that the key is valid as a vertical alignment. Valid + * keys are: TOP, CENTER, and BOTTOM. + * + * @param key The key to check. + * @param message The message of the exception to be thrown if the key is + * invalid. + * + * @return The key if it's valid. + * + * @throws IllegalArgumentException If the key is invalid. + */ + protected int checkVerticalKey(int key, String message) + { + if (key != TOP && key != BOTTOM && key != CENTER) + throw new IllegalArgumentException(message); + else + return key; + } + + /** + * This method returns the gap between the icon and the text. + * + * @return The gap between the icon and the text. + */ + public int getIconTextGap() + { + return iconTextGap; + } + + /** + * This method changes the "iconTextGap" property. The iconTextGap + * determines how much space there is between the icon and the text. + * + * @param newGap The gap between the icon and the text. + */ + public void setIconTextGap(int newGap) + { + if (iconTextGap != newGap) + { + firePropertyChange("iconTextGap", iconTextGap, newGap); + iconTextGap = newGap; + } + } + + /** + * This method returns the vertical alignment of the label. + * + * @return The vertical alignment of the label. + */ + public int getVerticalAlignment() + { + return verticalAlignment; + } + + /** + * This method changes the "verticalAlignment" property of the label. The + * vertical alignment determines how where the label will be placed + * vertically. If the alignment is not valid, it will default to the + * center. + * + * @param alignment The vertical alignment of the label. + */ + public void setVerticalAlignment(int alignment) + { + if (alignment == verticalAlignment) + return; + + int oldAlignment = verticalAlignment; + verticalAlignment = checkVerticalKey(alignment, "verticalAlignment"); + firePropertyChange("verticalAlignment", oldAlignment, verticalAlignment); + } + + /** + * This method returns the horziontal alignment of the label. + * + * @return The horizontal alignment of the label. + */ + public int getHorizontalAlignment() + { + return horizontalAlignment; + } + + /** + * This method changes the "horizontalAlignment" property. The horizontal + * alignment determines where the label will be placed horizontally. + * + * @param alignment The horizontal alignment of the label. + */ + public void setHorizontalAlignment(int alignment) + { + if (horizontalAlignment == alignment) + return; + + int oldAlignment = horizontalAlignment; + horizontalAlignment = checkHorizontalKey(alignment, "horizontalAlignment"); + firePropertyChange("horizontalAlignment", oldAlignment, + horizontalAlignment); + } + + /** + * This method returns the vertical text position of the label. + * + * @return The vertical text position of the label. + */ + public int getVerticalTextPosition() + { + return verticalTextPosition; + } + + /** + * This method changes the "verticalTextPosition" property of the label. The + * vertical text position determines where the text will be placed + * vertically relative to the icon. + * + * @param textPosition The vertical text position. + */ + public void setVerticalTextPosition(int textPosition) + { + if (textPosition != verticalTextPosition) + { + int oldPos = verticalTextPosition; + verticalTextPosition = checkVerticalKey(textPosition, + "verticalTextPosition"); + firePropertyChange("verticalTextPosition", oldPos, + verticalTextPosition); + } + } + + /** + * This method returns the horizontal text position of the label. + * + * @return The horizontal text position. + */ + public int getHorizontalTextPosition() + { + return horizontalTextPosition; + } + + /** + * This method changes the "horizontalTextPosition" property of the label. + * The horizontal text position determines where the text will be placed + * horizontally relative to the icon. + * + * @param textPosition The horizontal text position. + */ + public void setHorizontalTextPosition(int textPosition) + { + if (textPosition != horizontalTextPosition) + { + int oldPos = horizontalTextPosition; + horizontalTextPosition = checkHorizontalKey(textPosition, + "horizontalTextPosition"); + firePropertyChange("horizontalTextPosition", oldPos, + horizontalTextPosition); + } + } + + /** + * This method simply returns false if the current icon image (current icon + * will depend on whether the label is enabled) is not equal to the passed + * in image. + * + * @param img The image to check. + * @param infoflags The bitwise inclusive OR of ABORT, ALLBITS, ERROR, + * FRAMEBITS, HEIGHT, PROPERTIES, SOMEBITS, and WIDTH + * @param x The x position + * @param y The y position + * @param w The width + * @param h The height + * + * @return Whether the current icon image is equal to the image given. + */ + public boolean imageUpdate(Image img, int infoflags, int x, int y, int w, + int h) + { + Icon currIcon = isEnabled() ? icon : disabledIcon; + + // XXX: Is this the correct way to check for image equality? + if (currIcon != null && currIcon instanceof ImageIcon) + return (((ImageIcon) currIcon).getImage() == img); + + return false; + } + + /** + * This method returns the component that the label gives focus to when the + * mnemonic is activated. + * + * @return The component that gets focus when the label's mnemonic is + * activated. + */ + public Component getLabelFor() + { + return labelFor; + } + + /** + * This method changes the "labelFor" property. The component that the label + * is acting as a label for will request focus when the label's mnemonic + * is activated. + * + * @param c The component that gets focus when the label's mnemonic is + * activated. + */ + public void setLabelFor(Component c) + { + if (c != labelFor) + { + Component oldLabelFor = labelFor; + labelFor = c; + firePropertyChange("labelFor", oldLabelFor, labelFor); + } + } + + /** + * This method overrides setFont so that we can call for a repaint after the + * font is changed. + * + * @param f The font for this label. + */ + public void setFont(Font f) + { + super.setFont(f); + repaint(); + } + + /** + * DOCUMENT ME! + * + * @return + */ + public AccessibleContext getAccessibleContext() + { + return null; + } +} |