JTree通过单击行上的任何位置来选择节点
我从这里获取的代码可以通过单击行上的任何位置来选择JTree行。 它在单行选择模式下工作正常。 但是，我不知道如何修改它以处理多行选择。 当用户进行多重选择时（例如在按住鼠标左键的同时按住shift键或控制键），如何区分这种情况？
import java.awt.Rectangle;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
import javax.swing.JFrame;
import javax.swing.JTree;
import javax.swing.SwingUtilities;
import javax.swing.tree.DefaultMutableTreeNode;
import javax.swing.tree.TreeNode;
@SuppressWarnings("serial")
public class NavTree extends JTree {
private boolean fWholeRowSelectionEnabled;
private MouseListener fRowSelectionListener;
final NavTree fThis;
public NavTree(TreeNode rootNode) {
super(rootNode);
fThis = this;
init();
}
public NavTree() {
fThis = this;
init();
}
private void init() {
//setCellRenderer(new NavTreeCellRenderer());
fRowSelectionListener = new MouseAdapter() {
public void mousePressed(MouseEvent e) {
if (SwingUtilities.isLeftMouseButton(e)) {
int closestRow = fThis.getClosestRowForLocation(
e.getX(), e.getY());
Rectangle closestRowBounds = fThis.getRowBounds(closestRow);
if(e.getY() >= closestRowBounds.getY() &&
e.getY() < closestRowBounds.getY() +
closestRowBounds.getHeight()) {
if(e.getX() > closestRowBounds.getX() &&
closestRow < fThis.getRowCount()){
fThis.setSelectionRow(closestRow);
}
} else
fThis.setSelectionRow(-1);
}
}
};
setWholeRowSelectionEnabled(true);
}
public void setWholeRowSelectionEnabled(boolean wholeRowSelectionEnabled) {
fWholeRowSelectionEnabled = wholeRowSelectionEnabled;
if (fWholeRowSelectionEnabled)
addMouseListener(fRowSelectionListener);
else
removeMouseListener(fRowSelectionListener);
}
public boolean isWholeRowSelectionEnabled() {
return fWholeRowSelectionEnabled;
}
public static void main(String[] args) {
JFrame frame = new JFrame();
DefaultMutableTreeNode root = new DefaultMutableTreeNode("Root");
root.add(new DefaultMutableTreeNode("Child 1"));
root.add(new DefaultMutableTreeNode("Child 2"));
root.add(new DefaultMutableTreeNode("Child 3"));
NavTree tree = new NavTree(root);
frame.add(tree);
frame.setSize(200, 300);
frame.setVisible(true);
}
}
使用MouseEvent的修饰键信息。 有关更多信息，请参阅MouseEvent#getModifiersEx
PS：监听器注册包含一个错误
public void setWholeRowSelectionEnabled(boolean wholeRowSelectionEnabled) {
fWholeRowSelectionEnabled = wholeRowSelectionEnabled;
if (fWholeRowSelectionEnabled)
addMouseListener(fRowSelectionListener);
else
removeMouseListener(fRowSelectionListener);
}
将属性wholeRowSelectionEnabled设置为true应只注册侦听器一次。 如果该属性设置为true多次，您的代码会一次又一次地添加侦听器。 我的意思是，财产制定者应该是幂等的。
一个quickfix可以先删除它，如果启用则添加它
public void setWholeRowSelectionEnabled(boolean wholeRowSelectionEnabled) {
removeMouseListener(fRowSelectionListener);
fWholeRowSelectionEnabled = wholeRowSelectionEnabled;
if (fWholeRowSelectionEnabled)
addMouseListener(fRowSelectionListener);
}