Swing之JTree篇：在树节点前增加JCheckBox控件
斯诺克爱好者网：http://www.kkyule.com淘宝精品导航:http://www.nitaomei.com
在做Swing开发的时候可能经常会遇到类似的案例，关键还是需要实现TreeCellRenderer接口，重写getTreeCellRendererComponent方法
import java.awt.BorderLayout;import java.awt.Color;import java.awt.Component;import java.awt.Dimension;import java.awt.Graphics;import java.awt.GridLayout;import java.awt.event.ActionEvent;import java.awt.event.ActionListener;import java.awt.event.MouseAdapter;import java.awt.event.MouseEvent;import java.awt.event.WindowAdapter;import java.awt.event.WindowEvent;import java.util.Enumeration;import javax.swing.ButtonGroup;import javax.swing.Icon;import javax.swing.JButton;import javax.swing.JCheckBox;import javax.swing.JFrame;import javax.swing.JLabel;import javax.swing.JPanel;import javax.swing.JRadioButton;import javax.swing.JScrollPane;import javax.swing.JTextArea;import javax.swing.JTree;import javax.swing.UIManager;import javax.swing.border.TitledBorder;import javax.swing.plaf.ColorUIResource;import javax.swing.tree.DefaultMutableTreeNode;import javax.swing.tree.DefaultTreeModel;import javax.swing.tree.TreeCellRenderer;import javax.swing.tree.TreeNode;import javax.swing.tree.TreePath;import javax.swing.tree.TreeSelectionModel;public class CheckNodeTreeExample extends JFrame {public CheckNodeTreeExample() { super("CheckNode TreeExample"); String[] strs = {"swing", // 0 "platf", // 1 "basic", // 2 "metal", // 3 "JTree"}; // 4 CheckNode[] nodes = new CheckNode; for (int i=0;i<strs.length;i++) { nodes = new CheckNode(strs); } nodes.add(nodes); nodes.add(nodes); nodes.add(nodes); nodes.add(nodes); nodes.setSelected(true); JTree tree = new JTree( nodes ); tree.setCellRenderer(new CheckRenderer()); tree.getSelectionModel().setSelectionMode( TreeSelectionModel.SINGLE_TREE_SELECTION ); tree.putClientProperty("JTree.lineStyle", "Angled"); tree.addMouseListener(new NodeSelectionListener(tree)); JScrollPane sp = new JScrollPane(tree); ModePanel mp = new ModePanel(nodes); JTextArea textArea = new JTextArea(3,10); JScrollPane textPanel = new JScrollPane(textArea); JButton button = new JButton("print"); button.addActionListener( new ButtonActionListener(nodes, textArea)); JPanel panel = new JPanel(new BorderLayout()); panel.add(mp, BorderLayout.CENTER); panel.add(button, BorderLayout.SOUTH); getContentPane().add(sp, BorderLayout.CENTER); getContentPane().add(panel, BorderLayout.EAST); getContentPane().add(textPanel, BorderLayout.SOUTH);}class NodeSelectionListener extends MouseAdapter { JTree tree; NodeSelectionListener(JTree tree) { this.tree = tree; } public void mouseClicked(MouseEvent e) { int x = e.getX(); int y = e.getY(); int row = tree.getRowForLocation(x, y); TreePathpath = tree.getPathForRow(row); //TreePathpath = tree.getSelectionPath(); if (path != null) { CheckNode node = (CheckNode)path.getLastPathComponent(); boolean isSelected = ! (node.isSelected()); node.setSelected(isSelected); if (node.getSelectionMode() == CheckNode.DIG_IN_SELECTION) { if ( isSelected) { tree.expandPath(path); } else { tree.collapsePath(path); } } ((DefaultTreeModel) tree.getModel()).nodeChanged(node); // I need revalidate if node is root.but why? if (row == 0) { tree.revalidate(); tree.repaint(); } } }}class ModePanel extends JPanel implements ActionListener { CheckNode[] nodes; JRadioButton b_single, b_dig_in; ModePanel(CheckNode[] nodes) { this.nodes = nodes; setLayout(new GridLayout(2, 1)); setBorder(new TitledBorder("Check Mode")); ButtonGroup group = new ButtonGroup(); add(b_dig_in = new JRadioButton("DIG_IN")); add(b_single = new JRadioButton("SINGLE")); group.add(b_dig_in); group.add(b_single); b_dig_in.addActionListener(this); b_single.addActionListener(this); b_dig_in.setSelected(true); } public void actionPerformed(ActionEvent e) { int mode; if (b_single == e.getSource()) { mode = CheckNode.SINGLE_SELECTION; } else { mode = CheckNode.DIG_IN_SELECTION; } for (int i = 0; i < nodes.length; i++) { nodes.setSelectionMode(mode); } }}class ButtonActionListener implements ActionListener { CheckNode root; JTextArea textArea; ButtonActionListener(final CheckNode root, final JTextArea textArea) { this.root = root; this.textArea = textArea; } public void actionPerformed(ActionEvent ev) { Enumeration e = root.breadthFirstEnumeration(); while (e.hasMoreElements()) { CheckNode node = (CheckNode) e.nextElement(); if (node.isSelected()) { TreeNode[] nodes = node.getPath(); textArea.append("\n" + nodes.toString()); for (int i = 1; i < nodes.length; i++) { textArea.append("/" + nodes.toString()); } } } }}public static void main(String args[]) {// try {// UIManager.setLookAndFeel("com.sun.java.swing.plaf.windows.WindowsLookAndFeel");// } catch (Exception evt) {} CheckNodeTreeExample frame = new CheckNodeTreeExample(); frame.addWindowListener(new WindowAdapter() { public void windowClosing(WindowEvent e) { System.exit(0); } }); frame.setSize(300, 200); frame.setVisible(true);}}class CheckRenderer extends JPanel implements TreeCellRenderer {protected JCheckBox check;protected TreeLabel label;public CheckRenderer() { setLayout(null); add(check = new JCheckBox()); add(label = new TreeLabel()); check.setBackground(UIManager.getColor("Tree.textBackground")); label.setForeground(UIManager.getColor("Tree.textForeground"));}public Component getTreeCellRendererComponent(JTree tree, Object value, boolean isSelected, boolean expanded, boolean leaf, int row, boolean hasFocus) { String stringValue = tree.convertValueToText(value, isSelected, expanded, leaf, row, hasFocus); setEnabled(tree.isEnabled()); check.setSelected(((CheckNode) value).isSelected()); label.setFont(tree.getFont()); label.setText(stringValue); label.setSelected(isSelected); label.setFocus(hasFocus); if (leaf) { label.setIcon(UIManager.getIcon("Tree.leafIcon")); } else if (expanded) { label.setIcon(UIManager.getIcon("Tree.openIcon")); } else { label.setIcon(UIManager.getIcon("Tree.closedIcon")); } return this;}public Dimension getPreferredSize() { Dimension d_check = check.getPreferredSize(); Dimension d_label = label.getPreferredSize(); return new Dimension(d_check.width + d_label.width, (d_check.height < d_label.height ? d_label.height : d_check.height));}public void doLayout() { Dimension d_check = check.getPreferredSize(); Dimension d_label = label.getPreferredSize(); int y_check = 0; int y_label = 0; if (d_check.height < d_label.height) { y_check = (d_label.height - d_check.height) / 2; } else { y_label = (d_check.height - d_label.height) / 2; } check.setLocation(0, y_check); check.setBounds(0, y_check, d_check.width, d_check.height); label.setLocation(d_check.width, y_label); label.setBounds(d_check.width, y_label, d_label.width, d_label.height);}public void setBackground(Color color) { if (color instanceof ColorUIResource) color = null; super.setBackground(color);}public class TreeLabel extends JLabel { boolean isSelected; boolean hasFocus; public TreeLabel() { } public void setBackground(Color color) { if (color instanceof ColorUIResource) color = null; super.setBackground(color); } public void paint(Graphics g) { String str; if ((str = getText()) != null) { if (0 < str.length()) { if (isSelected) { g.setColor(UIManager .getColor("Tree.selectionBackground")); } else { g.setColor(UIManager.getColor("Tree.textBackground")); } Dimension d = getPreferredSize(); int imageOffset = 0; Icon currentI = getIcon(); if (currentI != null) { imageOffset = currentI.getIconWidth() + Math.max(0, getIconTextGap() - 1); } g.fillRect(imageOffset, 0, d.width - 1 - imageOffset, d.height); if (hasFocus) { g.setColor(UIManager .getColor("Tree.selectionBorderColor")); g.drawRect(imageOffset, 0, d.width - 1 - imageOffset, d.height - 1); } } } super.paint(g); } public Dimension getPreferredSize() { Dimension retDimension = super.getPreferredSize(); if (retDimension != null) { retDimension = new Dimension(retDimension.width + 3, retDimension.height); } return retDimension; } public void setSelected(boolean isSelected) { this.isSelected = isSelected; } public void setFocus(boolean hasFocus) { this.hasFocus = hasFocus; }}}class CheckNode extends DefaultMutableTreeNode {public final static int SINGLE_SELECTION = 0;public final static int DIG_IN_SELECTION = 4;protected int selectionMode;protected boolean isSelected;public CheckNode() { this(null);}public CheckNode(Object userObject) { this(userObject, true, false);}public CheckNode(Object userObject, boolean allowsChildren, boolean isSelected) { super(userObject, allowsChildren); this.isSelected = isSelected; setSelectionMode(DIG_IN_SELECTION);}public void setSelectionMode(int mode) { selectionMode = mode;}public int getSelectionMode() { return selectionMode;}public void setSelected(boolean isSelected) { this.isSelected = isSelected; if ((selectionMode == DIG_IN_SELECTION) && (children != null)) { Enumeration e = children.elements(); while (e.hasMoreElements()) { CheckNode node = (CheckNode) e.nextElement(); node.setSelected(isSelected); } }}public boolean isSelected() { return isSelected;}}
页:
[1]