如何更改JTextPane的输入属性？

Question

我使用了JButton,当点击按钮时,运行这些代码:

StyledDocument doc = (StyledDocument) textPane.getDocument(); 
MutableAttributeSet attr = new SimpleAttributeSet(); 
int p0=textPane.getSelectionStart();
int p1=textPane.getSelectionEnd();
if(p0!=p1){
   StyleConstants.setForeground(attr, Color.RED); 
   doc.setCharacterAttributes(p0,p1-p0, attr,false);
}
textPane.getInputAttributes().addAttributes(attr);

从p0到p1的字符确实变为红色

但我输入的字符仍然是黑色,而不是红色:(

例子:

我键入"12345"并选择"234".

新的5还是黑色的.

但如果我输入"1234"并选择"234".

新的5将是红色的.

即使没有"textPane.getInputAttributes().addAttributes(attr);"

Answer 1

问题是getInputAttribute反映了当前插入符号位置的characters属性.

1. 你选择"234"(插入符号在4之后) - > InputAttributes反映"234"的那些
2. 您在"234"和当前InputAttributes(应该是相同的)上应用红色样式前景
3. 在"5" - > InputAttributes更新后移动插入符并反映"5"的插入符号

现在,这里有一些代码可以让你自己受到启发(这不是真正可操作的),你可能需要听取插入符号的动作(很难在不知道你想要实现的目的的情况下判断):

import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JTextPane;
import javax.swing.SwingUtilities;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;
import javax.swing.text.MutableAttributeSet;
import javax.swing.text.SimpleAttributeSet;
import javax.swing.text.StyleConstants;
import javax.swing.text.StyledDocument;

public class TestTextPane {

    protected void initUI() {
        JFrame frame = new JFrame(TestTextPane.class.getSimpleName());
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        final JTextPane textPane2 = new JTextPane();
        textPane2.setText("12345");
        frame.add(textPane2);
        JButton button = new JButton("Make it red");
        button.addActionListener(new ActionListener() {

            @Override
            public void actionPerformed(ActionEvent e) {
                final SimpleAttributeSet set = new SimpleAttributeSet();
                StyleConstants.setForeground(set, Color.RED);
                int p0 = textPane2.getSelectionStart();
                int p1 = textPane2.getSelectionEnd();
                if (p0 != p1) {
                    StyledDocument doc = textPane2.getStyledDocument();
                    doc.setCharacterAttributes(p0, p1 - p0, set, false);
                }
                SwingUtilities.invokeLater(new Runnable() {
                    @Override
                    public void run() {
                        textPane2.getCaret().setDot(textPane2.getText().length());
                        MutableAttributeSet inputAttributes = textPane2.getInputAttributes();
                        inputAttributes.addAttributes(set);
                    }
                });

            }
        });
        button.setFocusable(false);
        frame.add(button, BorderLayout.SOUTH);
        frame.setSize(600, 400);
        frame.setVisible(true);
    }

    public static void main(String[] args) {
        try {
            UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
        } catch (ClassNotFoundException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (InstantiationException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (IllegalAccessException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (UnsupportedLookAndFeelException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        SwingUtilities.invokeLater(new Runnable() {

            @Override
            public void run() {
                TestTextPane t = new TestTextPane();
                t.initUI();
            }
        });
    }

}