Java tutorial
/* * Copyright (c) 2008, SQL Power Group Inc. * * This file is part of SQL Power Library. * * SQL Power Library 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 3 of the License, or * (at your option) any later version. * * SQL Power Library 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 this program. If not, see <http://www.gnu.org/licenses/>. */ package ca.sqlpower.swingui; import java.awt.Color; import java.awt.Dimension; import java.awt.Font; import java.awt.GraphicsEnvironment; import java.beans.PropertyChangeEvent; import java.beans.PropertyChangeListener; import java.beans.PropertyChangeSupport; import java.util.Arrays; import javax.swing.JDialog; import javax.swing.JFrame; import javax.swing.JList; import javax.swing.JPanel; import javax.swing.JScrollPane; import javax.swing.JSpinner; import javax.swing.JTextArea; import javax.swing.SpinnerNumberModel; import javax.swing.SwingUtilities; import javax.swing.event.ChangeEvent; import javax.swing.event.ChangeListener; import javax.swing.event.ListSelectionEvent; import javax.swing.event.ListSelectionListener; import org.apache.log4j.Logger; import ca.sqlpower.dao.session.SPFontLoader; import com.jgoodies.forms.builder.DefaultFormBuilder; import com.jgoodies.forms.layout.CellConstraints; import com.jgoodies.forms.layout.FormLayout; /** * This class is a {@link DataEntryPanel} that asks the user to pick a font. */ public class FontSelector implements DataEntryPanel { private static final Logger logger = Logger.getLogger(FontSelector.class); private static enum FontStyle { PLAIN("Plain", Font.PLAIN), BOLD("Bold", Font.BOLD), ITALIC("Italic", Font.ITALIC), BOLD_ITALIC("Bold Italic", Font.BOLD | Font.ITALIC); private final String humanName; private final int styleCode; FontStyle(String name, int styleCode) { humanName = name; this.styleCode = styleCode; } /** * Returns a font derived from the given font which has the style * specified by this enum constant. * * @param f * The original font * @return A new font with the same size and family as f, but with this * enum constant's style. */ public Font apply(Font f) { return f.deriveFont(styleCode); } @Override public String toString() { return humanName; } public static FontStyle forCode(int styleCode) { for (FontStyle sty : values()) { if (styleCode == sty.styleCode) { return sty; } } throw new IllegalArgumentException("Unknown font style code: " + styleCode); } public int getStyleCode() { return styleCode; } } private PropertyChangeSupport pcs = new PropertyChangeSupport(this); /** * The font the user has chosen. This is updated whenever any of the * font choosing components fires a change event. */ private Font selectedFont; /** * A list populated with all font names available on the local system. */ private final JList fontNameList; /** * A list populated with a number of common font sizes the user might want * to pick. Choosing an item on this list fills in the value in the font * size text field. */ private final JList fontSizeList; /** * The field that actually specifies the font size. Can be updated directly * to any positive integer value, or by clicking a preset value in the * {@link #fontSizeList}. */ private final JSpinner fontSizeSpinner; /** * The font style chooser (bold, italic, bold italic, plain). */ private final JList styleChoice; /** The list of font sizes */ private static final Integer[] FONT_SIZES = { 4, 5, 6, 7, 8, 10, 11, 12, 13, 14, 15, 16, 18, 20, 24, 30, 36, 40, 48, 60, 72, 96, 144 }; /** * The display area. */ private final JTextArea previewArea = new JTextArea("The Quick Wabit Architected the Loaded Matchmaker"); /** * The panel we return as this data entry panel's GUI. */ private final JPanel panel; /** * The original font we started with. If this data entry panel is canceled, * the user's current choice will revert to this value. */ private final Font originalFont; private final SPFontLoader fontLoader; private class SelectionHandler implements ChangeListener, ListSelectionListener { boolean updatingListSelection = false; public void stateChanged(ChangeEvent e) { if (updatingListSelection) return; try { updatingListSelection = true; Integer newSize = (Integer) fontSizeSpinner.getValue(); int newSizeIndexInList = Arrays.binarySearch(FONT_SIZES, newSize); if (newSizeIndexInList >= 0) { fontSizeList.setSelectedIndex(newSizeIndexInList); fontSizeList.ensureIndexIsVisible(newSizeIndexInList); } else { fontSizeList.clearSelection(); } } finally { updatingListSelection = false; } previewFont(); } public void valueChanged(ListSelectionEvent e) { previewFont(); } } /** * This constructor will create the Font Selector given a parent frame and a * previous font. * * @param font The font to start with in the preview dialog. If null, the system * default font will be used. */ public FontSelector(Font font) { this(font == null ? Font.decode(null) : font, GraphicsEnvironment.getLocalGraphicsEnvironment().getAvailableFontFamilyNames(), null); } public FontSelector(Font font, String[] fontList, SPFontLoader fontLoader) { this.fontLoader = fontLoader; if (font == null) { if (fontList == null || fontList.length == 0) { throw new IllegalArgumentException("The fontList parameter requires at least one valid font."); } font = Font.decode(fontList[0]); if (font == null) { throw new IllegalArgumentException("The fontList[0] element cannot be loaded."); } } logger.debug("Creating new font selector with given font: " + font); this.originalFont = font; SelectionHandler selectionHandler = new SelectionHandler(); fontNameList = new JList(fontList); fontNameList.addListSelectionListener(selectionHandler); fontSizeSpinner = new JSpinner(new SpinnerNumberModel(font.getSize(), 1, 200, 1)); fontSizeSpinner.addChangeListener(selectionHandler); fontSizeList = new JList(FONT_SIZES); fontSizeList.addListSelectionListener(new ListSelectionListener() { public void valueChanged(ListSelectionEvent e) { if (fontSizeList.getSelectedValue() != null) { fontSizeSpinner.setValue((Integer) fontSizeList.getSelectedValue()); } } }); styleChoice = new JList(FontStyle.values()); styleChoice.setSelectedValue(FontStyle.forCode(font.getStyle()), true); styleChoice.addListSelectionListener(selectionHandler); FormLayout layout = new FormLayout("pref:grow, 4dlu, pref, 4dlu, pref", "pref, 4dlu, pref, 4dlu, fill:pref:grow"); layout.setHonorsVisibility(true); DefaultFormBuilder builder = new DefaultFormBuilder(layout); CellConstraints cc = new CellConstraints(); builder.add(new JScrollPane(fontNameList), cc.xywh(1, 1, 1, 3)); builder.add(fontSizeSpinner, cc.xywh(3, 1, 1, 1)); builder.add(new JScrollPane(fontSizeList), cc.xywh(3, 3, 1, 1)); builder.add(new JScrollPane(styleChoice), cc.xywh(5, 1, 1, 3)); previewArea.setBackground(Color.WHITE); previewArea.setPreferredSize(new Dimension(300, 100)); builder.add(previewArea, cc.xywh(1, 5, 5, 1)); // Set defaults after creating layout so the "scroll to visible" works fontSizeList.setSelectedValue(Integer.valueOf(font.getSize()), true); fontNameList.setSelectedValue(font.getFamily(), true); logger.debug( "Set family list to \"" + font.getFamily() + "\" and size to " + Integer.valueOf(font.getSize())); panel = builder.getPanel(); previewFont(); // ensure view is up to date! } /** * Updates the {@link #selectedFont} and the font in the preview area. This * method gets called from the change handlers installed on all the chooser * components. */ private void previewFont() { String name = (String) fontNameList.getSelectedValue(); FontStyle style = (FontStyle) styleChoice.getSelectedValue(); int size = ((Integer) fontSizeSpinner.getValue()).intValue(); if (fontLoader == null) { setSelectedFont(new Font(name, style.getStyleCode(), size)); } else { Font font = fontLoader.loadFontFromName(name); font = font.deriveFont(style.getStyleCode()); font = font.deriveFont(Float.valueOf(String.valueOf(size))); setSelectedFont(font); } } /** * Returns the font the user has constructed through the choices in this * font selector. */ public Font getSelectedFont() { return selectedFont; } public void setSelectedFont(Font selectedFont) { Font oldFont = this.selectedFont; this.selectedFont = selectedFont; pcs.firePropertyChange("selectedFont", oldFont, selectedFont); previewArea.setFont(selectedFont); } public JPanel getPanel() { return panel; } public boolean applyChanges() { return true; } /** * Reverts to the original font. */ public void discardChanges() { setSelectedFont(originalFont); } public boolean hasUnsavedChanges() { return false; } /** * Sets the text that will appear in the preview area. If you do not * call this method, the font selector will show its catchy default * phrase. */ public void setPreviewText(String text) { previewArea.setText(text); } /** * Returns the current preview text. Keep in mind the text is in an * editable text area, so the user could have modified the text by the * time you call this method, and the entered text could be multi-line. */ public String getPreviewText() { return previewArea.getText(); } public void setShowingPreview(boolean show) { previewArea.setVisible(show); } public boolean isShowingPreview() { return previewArea.isVisible(); } public static void main(String[] args) { SwingUtilities.invokeLater(new Runnable() { public void run() { final FontSelector fs = new FontSelector(Font.decode("Courier bold 20")); fs.addPropertyChangeListener(new PropertyChangeListener() { public void propertyChange(PropertyChangeEvent evt) { System.out.println("New font selection: " + fs.getSelectedFont()); } }); JFrame dummyFrame = new JFrame(); JDialog d = DataEntryPanelBuilder.createDataEntryPanelDialog(fs, dummyFrame, "Font Selector Demo!", "Yeehaw"); d.setModal(true); d.setVisible(true); System.out.println("Selected font: " + fs.getSelectedFont()); d.dispose(); dummyFrame.dispose(); } }); } /** * Adds a property change listener that will be notified every time * the selected font has changed. The property name is "selectedFont". */ public void addPropertyChangeListener(PropertyChangeListener listener) { pcs.addPropertyChangeListener(listener); } public PropertyChangeListener[] getPropertyChangeListeners() { return pcs.getPropertyChangeListeners(); } public void removePropertyChangeListener(PropertyChangeListener listener) { pcs.removePropertyChangeListener(listener); } }