JTextPane-获取组件值 [英] JTextPane - get component values
问题描述
我有JTextPane,在其中插入了2个JLabel.如果单击了任何标签,它们会将内容从AAA更改为被单击.
I have JTextPane, where are inserted 2 JLabels. If any of the labels are clicked, they change content from AAA to clicked.
此代码遍历JTextPane中的元素:
This code iterates over the elements in the JTextPane:
for(int i = 0; i < tp.getDocument().getLength(); i++) {
System.out.println(((StyledDocument) tp.getDocument()).getCharacterElement(i));
}
如何访问标签以将单击的""AAAA"打印到标准输出?
package texteditor;
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import javax.swing.BorderFactory;
import javax.swing.ImageIcon;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JMenuItem;
import javax.swing.JPanel;
import javax.swing.JPopupMenu;
import javax.swing.JScrollPane;
import javax.swing.JTextPane;
import javax.swing.border.BevelBorder;
import javax.swing.border.TitledBorder;
import javax.swing.text.BadLocationException;
import javax.swing.text.StyledDocument;
import javax.swing.JButton;
public class JTextPaneExample extends JPanel {
private JTextPane tp;
public JTextPaneExample() {
setLayout(new BorderLayout(0, 0));
JPanel panel = new JPanel();
panel.setBorder(new TitledBorder(null, "Text Content", TitledBorder.LEADING, TitledBorder.TOP, null, null));
add(panel, BorderLayout.CENTER);
panel.setLayout(new BorderLayout(0, 0));
JScrollPane scrollPane = new JScrollPane();
panel.add(scrollPane, BorderLayout.CENTER);
tp = new JTextPane();
tp.setEditable(false);
scrollPane.setViewportView(tp);
JLabel lbl = new JLabel("AAAA ");
lbl.setOpaque(true);
lbl.setBorder(BorderFactory.createLineBorder(Color.black, 1));
lbl.addMouseListener(new LabelAdapter2(lbl));
tp.insertComponent(lbl);
lbl = new JLabel("BBBB ");
lbl.setOpaque(true);
lbl.setBorder(BorderFactory.createLineBorder(Color.black, 1));
lbl.addMouseListener(new LabelAdapter2(lbl));
tp.insertComponent(lbl);
JButton btnNewButton = new JButton("Write content");
btnNewButton.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
iterateOverContent(tp);
}
});
panel.add(btnNewButton, BorderLayout.SOUTH);
}
private void iterateOverContent(JTextPane tp2) {
for(int i = 0; i < tp.getDocument().getLength(); i++) {
System.out.println(((StyledDocument) tp.getDocument()).getCharacterElement(i));
}
}
private class LabelAdapter2 extends MouseAdapter {
private JLabel lblNewLabel;
public LabelAdapter2(JLabel lbl) {
this.lblNewLabel = lbl;
}
public void mouseClicked(MouseEvent evt) {
lblNewLabel.setText("clicked");
}
}
public static void main(String[] args) {
JFrame frame = new JFrame("GoBoard");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.getContentPane().add(new JTextPaneExample());
frame.setPreferredSize(new Dimension(400, 400));
frame.pack();
frame.setVisible(true);
}
}
推荐答案
我调查了您的问题并找到了解决方案:
i looked into your Question and found a Solution:
只需替换您的方法即可使用以下方法迭代TextPane的元素:
just replace your method to iterate the elements of the TextPane with this:
private void iterateOverContent(JTextPane tp2) {
for(int i = 0; i < tp.getDocument().getLength(); i++) {
Element elem = ((StyledDocument) tp.getDocument()).getCharacterElement(i);
AttributeSet as = elem.getAttributes();
if (as.containsAttribute(AbstractDocument.ElementNameAttribute, StyleConstants.ComponentElementName)) {
if(StyleConstants.getComponent(as) instanceof JLabel) {
JLabel myLabel = (JLabel)StyleConstants.getComponent(as);
System.out.println(myLabel.getText());
}
}
System.out.println(((StyledDocument) tp.getDocument()).getCharacterElement(i));
}
}
如您所见,
我首先将元素保存到新变量中,然后读出所有属性(是的,代码可能会短很多,但是这样更清楚了-我希望:-)) 之后,我们检查属性是否说这个元素是一个组件.
as you can see, i first save the element into a new variable and then read out all the attributes (yes, the code could be alot shorter, but this way it is more clear - i hope :-) ) After that, we check if the attributes say, that this element is a component.
然后是重要的部分:我们可以通过StyleConstants.getComponent方法从属性集中获取一个Component.
then the important part: we can get a Component from the attribute set via the StyleConstants.getComponent Method.
最后,只需进行一些完整性检查,看看我们是否真的可以将其转换为JLabel.
Finally just some sanity checks, to see if we can really typecast it to a JLabel.
最诚挚的问候, 大卫
这篇关于JTextPane-获取组件值的文章就介绍到这了,希望我们推荐的答案对大家有所帮助,也希望大家多多支持IT屋!