Java tutorial
/* Core SWING Advanced Programming By Kim Topley ISBN: 0 13 083292 8 Publisher: Prentice Hall */ import java.awt.Color; import java.awt.Container; import java.awt.Graphics; import java.awt.Insets; import java.awt.Rectangle; import java.awt.Shape; import javax.swing.BorderFactory; import javax.swing.JFrame; import javax.swing.JScrollPane; import javax.swing.JTextPane; import javax.swing.SwingUtilities; import javax.swing.UIManager; import javax.swing.border.Border; import javax.swing.text.AbstractDocument; import javax.swing.text.AttributeSet; import javax.swing.text.DefaultStyledDocument; import javax.swing.text.Element; import javax.swing.text.MutableAttributeSet; import javax.swing.text.ParagraphView; import javax.swing.text.SimpleAttributeSet; import javax.swing.text.Style; import javax.swing.text.StyleConstants; import javax.swing.text.StyleContext; import javax.swing.text.StyledEditorKit; import javax.swing.text.View; import javax.swing.text.ViewFactory; public class ExtendedParagraphExample { public static void createDocumentStyles(StyleContext sc) { Style defaultStyle = sc.getStyle(StyleContext.DEFAULT_STYLE); // Create and add the main document style Style mainStyle = sc.addStyle(mainStyleName, defaultStyle); StyleConstants.setLeftIndent(mainStyle, 16); StyleConstants.setRightIndent(mainStyle, 16); StyleConstants.setFirstLineIndent(mainStyle, 16); StyleConstants.setFontFamily(mainStyle, "serif"); StyleConstants.setFontSize(mainStyle, 12); // Create and add the constant width style Style cwStyle = sc.addStyle(charStyleName, null); StyleConstants.setFontFamily(cwStyle, "monospaced"); StyleConstants.setForeground(cwStyle, Color.white); // Create and add the heading style Style heading2Style = sc.addStyle(heading2StyleName, null); StyleConstants.setForeground(heading2Style, Color.red); StyleConstants.setFontSize(heading2Style, 16); StyleConstants.setFontFamily(heading2Style, "serif"); StyleConstants.setBold(heading2Style, true); StyleConstants.setLeftIndent(heading2Style, 8); StyleConstants.setFirstLineIndent(heading2Style, 0); // Create and add the extended para styles Style paraStyle = sc.addStyle(paraStyleName, null); Color bgColor = Color.gray; ExtendedStyleConstants.setParagraphBackground(paraStyle, bgColor); ExtendedStyleConstants.setParagraphBorder(paraStyle, BorderFactory.createCompoundBorder(BorderFactory.createEmptyBorder(2, 2, 2, 2), BorderFactory.createCompoundBorder( BorderFactory.createEtchedBorder(bgColor.brighter(), bgColor.darker()), BorderFactory.createEmptyBorder(4, 4, 4, 4)))); } public static void addText(JTextPane pane, StyleContext sc, Style logicalStyle, Paragraph[] content) { // The outer loop adds paragraphs, while the // inner loop adds character runs. int paragraphs = content.length; for (int i = 0; i < paragraphs; i++) { Run[] runs = content[i].content; for (int j = 0; j < runs.length; j++) { pane.setCharacterAttributes( runs[j].styleName == null ? SimpleAttributeSet.EMPTY : sc.getStyle(runs[j].styleName), true); pane.replaceSelection(runs[j].content); } // At the end of the paragraph, add the logical style and // any overriding paragraph style and then terminate the // paragraph with a newline. pane.setParagraphAttributes(SimpleAttributeSet.EMPTY, true); if (logicalStyle != null) { pane.setLogicalStyle(logicalStyle); } if (content[i].styleName != null) { pane.setParagraphAttributes(sc.getStyle(content[i].styleName), false); } if (i != paragraphs - 1) { pane.replaceSelection("\n"); } } } public static void main(String[] args) { try { UIManager.setLookAndFeel("com.sun.java.swing.plaf.windows.WindowsLookAndFeel"); } catch (Exception evt) { } JFrame f = new JFrame("Extended Paragraph Example"); // Create the StyleContext, the document and the pane final StyleContext sc = new StyleContext(); final DefaultStyledDocument doc = new DefaultStyledDocument(sc); final JTextPane pane = new JTextPane(doc); pane.setEditorKit(new ExtendedStyledEditorKit()); try { // Add the text and apply the styles SwingUtilities.invokeAndWait(new Runnable() { public void run() { // Build the styles createDocumentStyles(sc); // Add the text addText(pane, sc, sc.getStyle(mainStyleName), content); } }); } catch (Exception e) { System.out.println("Exception when constructing document: " + e); System.exit(1); } f.getContentPane().add(new JScrollPane(pane)); f.setSize(400, 300); f.setVisible(true); } // Style names public static final String mainStyleName = "MainStyle"; public static final String heading2StyleName = "Heading2"; public static final String charStyleName = "ConstantWidth"; public static final String paraStyleName = "ExtendedPara"; // Inner classes used to define paragraph structure public static class Run { public Run(String styleName, String content) { this.styleName = styleName; this.content = content; } public String styleName; public String content; } public static class Paragraph { public Paragraph(String styleName, Run[] content) { this.styleName = styleName; this.content = content; } public String styleName; public Run[] content; } public static final Paragraph[] content = new Paragraph[] { new Paragraph(heading2StyleName, new Run[] { new Run(null, "Attributes, Styles and Style Contexts") }), new Paragraph(paraStyleName, new Run[] { new Run(null, "The simple "), new Run(charStyleName, "PlainDocument"), new Run(null, " class that you saw in the previous " + "chapter is only capable of holding text. " + "The more complex text components use a more " + "sophisticated model that implements the "), new Run(charStyleName, "StyledDocument"), new Run(null, " interface. "), new Run(charStyleName, "StyledDocument"), new Run(null, " is a sub-interface of "), new Run(charStyleName, "Document"), new Run(null, " that contains methods for manipulating attributes " + "that control the way in which the text in the " + "document is displayed. The Swing text package " + "contains a concrete implementation of "), new Run(charStyleName, "StyledDocument"), new Run(null, " called "), new Run(charStyleName, "DefaultStyledDocument"), new Run(null, " that is used as the default model for "), new Run(charStyleName, "JTextPane"), new Run(null, " and is also the base class from which " + "more specific models, such as the "), new Run(charStyleName, "HTMLDocument"), new Run(null, " class that handles input in HTML format, can be " + "created. In order to make use of "), new Run(charStyleName, "DefaultStyledDocument"), new Run(null, " and "), new Run(charStyleName, "JTextPane"), new Run(null, " you need to understand how Swing represents " + "and uses attributes.") }) }; } class ExtendedStyleConstants { public ExtendedStyleConstants(String name) { this.name = name; } public String toString() { return name; } /** * The border to be used for a paragraph. Type is javax.swing.border.Border */ public static final Object ParagraphBorder = ExtendedParagraphConstants.ParagraphBorder; /** * The background to be used for a paragraph. Type is java.awt.Color */ public static final Object ParagraphBackground = ExtendedParagraphConstants.ParagraphBackground; /* Adds the border attribute */ public static void setParagraphBorder(MutableAttributeSet a, Border b) { a.addAttribute(ParagraphBorder, b); } /* Gets the border attribute */ public static Border getParagraphBorder(AttributeSet a) { return (Border) a.getAttribute(ParagraphBorder); } /* Adds the paragraph background attribute */ public static void setParagraphBackground(MutableAttributeSet a, Color c) { a.addAttribute(ParagraphBackground, c); } /* Gets the paragraph background attribute */ public static Color getParagraphBackground(AttributeSet a) { return (Color) a.getAttribute(ParagraphBackground); } /* A typesafe collection of extended paragraph attributes */ public static class ExtendedParagraphConstants extends ExtendedStyleConstants implements AttributeSet.ParagraphAttribute { /** * The paragraph border attribute. */ public static final Object ParagraphBorder = new ExtendedParagraphConstants("ParagraphBorder"); /** * The paragraph background attribute. */ public static final Object ParagraphBackground = new ExtendedParagraphConstants("ParagraphBackground"); private ExtendedParagraphConstants(String name) { super(name); } } protected String name; // Name of an attribute } class ExtendedStyledEditorKit extends StyledEditorKit { public Object clone() { return new ExtendedStyledEditorKit(); } public ViewFactory getViewFactory() { return defaultFactory; } /* The extended view factory */ static class ExtendedStyledViewFactory implements ViewFactory { public View create(Element elem) { String elementName = elem.getName(); if (elementName != null) { if (elementName.equals(AbstractDocument.ParagraphElementName)) { return new ExtendedParagraphView(elem); } } // Delegate others to StyledEditorKit return styledEditorKitFactory.create(elem); } } private static final ViewFactory styledEditorKitFactory = (new StyledEditorKit()).getViewFactory(); private static final ViewFactory defaultFactory = new ExtendedStyledViewFactory(); } class ExtendedParagraphView extends ParagraphView { public ExtendedParagraphView(Element elem) { super(elem); } // Override ParagraphView methods protected void setPropertiesFromAttributes() { AttributeSet attr = getAttributes(); if (attr != null) { super.setPropertiesFromAttributes(); paraInsets = new Insets(getTopInset(), getLeftInset(), getBottomInset(), getRightInset()); border = ExtendedStyleConstants.getParagraphBorder(attr); bgColor = ExtendedStyleConstants.getParagraphBackground(attr); if (bgColor != null && border == null) { // Provide a small margin if the background // is being filled and there is no border border = smallBorder; } if (border != null) { Insets borderInsets = border.getBorderInsets(getContainer()); setInsets((short) (paraInsets.top + borderInsets.top), (short) (paraInsets.left + borderInsets.left), (short) (paraInsets.bottom + borderInsets.bottom), (short) (paraInsets.right + borderInsets.right)); } } } public void paint(Graphics g, Shape a) { Container comp = getContainer(); Rectangle alloc = new Rectangle(a.getBounds()); alloc.x += paraInsets.left; alloc.y += paraInsets.top; alloc.width -= paraInsets.left + paraInsets.right; alloc.height -= paraInsets.top + paraInsets.bottom; if (bgColor != null) { Color origColor = g.getColor(); g.setColor(bgColor); g.fillRect(alloc.x, alloc.y, alloc.width, alloc.height); g.setColor(origColor); } if (border != null) { // Paint the border border.paintBorder(comp, g, alloc.x, alloc.y, alloc.width, alloc.height); } super.paint(g, a); // Note: pass ORIGINAL allocation } // Attribute cache protected Color bgColor; // Background color, or null for transparent. protected Border border; // Border, or null for no border protected Insets paraInsets; // Original paragraph insets protected static final Border smallBorder = BorderFactory.createEmptyBorder(2, 2, 2, 2); }