在JTextPane java swing中填充直线矩形后无法与视图同步
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【中文标题】在JTextPane java swing中填充直线矩形后无法与视图同步【英文标题】:Can not sync with view after filling rectange of line in JTextPane java swing 【发布时间】:2018-12-03 11:15:21 【问题描述】:我在突出显示 jtextpane java swing 中的特定行时遇到了麻烦。我有一个名为 Solution 和 Modified LinePainter 的主类,我在网上找到了它。每当调用 sl() 函数时,它都会绘制特定的行。那是由于调用paint方法。我用 paint 方法打印了虚拟线。那条虚拟线经常打印。这意味着在预定义的时间段后调用paint方法。运行代码后,我发现每当我最大化或最小化窗口时,它只会显示正确的所需行突出显示。我希望每当我调用 sl 函数时(sl 表示设置行表示突出显示传递的行号)。应该改变或学习什么?感谢阅读。
Solution.java 文件
import javax.swing.*;
import java.util.Scanner;
public class Solution
public static void main(String[] args)
JFrame f = new JFrame("Swing Paint Demo");
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
JTextPane jTextPane=new JTextPane();
jTextPane.setText("abc\nbcd\nmm\njjjjj");
LinePainter linePainter=new LinePainter(jTextPane);
Scanner sc=new Scanner(System.in);
f.add(jTextPane);
f.setSize(250,250);
f.setVisible(true);
int x=sc.nextInt();
linePainter.sl(2);
x=sc.nextInt();
linePainter.sl(3);
LinePainter.java 文件
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.event.*;
import javax.swing.text.*;
/*
* Track the movement of the Caret by painting a background line at the
* current caret position.
*/
public class LinePainter
implements Highlighter.HighlightPainter, CaretListener, MouseListener, MouseMotionListener
private JTextComponent component;
private Color color;
private Rectangle lastView;
/*
* The line color will be calculated automatically by attempting
* to make the current selection lighter by a factor of 1.2.
*
* @param component text component that requires background line painting
*/
public LinePainter(JTextComponent component)
this(component, null);
setLighter(component.getSelectionColor());
/*
* Manually control the line color
*
* @param component text component that requires background line painting
* @param color the color of the background line
*/
public LinePainter(JTextComponent component, Color color)
this.component = component;
setColor( color );
// Add listeners so we know when to change highlighting
component.addCaretListener( this );
component.addMouseListener( this );
component.addMouseMotionListener( this );
// Turn highlighting on by adding a dummy highlight
try
component.getHighlighter().addHighlight(0, 0, this);
catch(BadLocationException ble)
/*
* You can reset the line color at any time
*
* @param color the color of the background line
*/
public void setColor(Color color)
this.color = color;
/*
* Calculate the line color by making the selection color lighter
*
* @return the color of the background line
*/
public void setLighter(Color color)
int red = Math.min(255, (int)(color.getRed() * 1.2));
int green = Math.min(255, (int)(color.getGreen() * 1.2));
int blue = Math.min(255, (int)(color.getBlue() * 1.2));
setColor(new Color(red, green, blue));
public int ln=1;
public void sl(int l) ln=l;
System.out.println("hii");
// Paint the background highlight
public void paint(Graphics g, int p0, int p1, Shape bounds, JTextComponent c)
try
System.out.println("calling paint");
// resetHighlight();
Rectangle r = c.modelToView((c).getDocument().getDefaultRootElement().getElement(ln-1).getStartOffset());
g.setColor( color );
// if(lastView != null)
// g.clearRect(0,lastView.y,c.getWidth(),lastView.height);
//
g.fillRect(0, r.y, c.getWidth(), r.height);
// if (lastView == null)
// lastView = r;
catch(BadLocationException ble) System.out.println(ble);
/*
* Caret position has changed, remove the highlight
*/
private void resetHighlight()
System.out.println("reset");
// Use invokeLater to make sure updates to the Document are completed,
// otherwise Undo processing causes the modelToView method to loop.
SwingUtilities.invokeLater(new Runnable()
public void run()
try
Rectangle currentView = component.modelToView(component.getDocument().getDefaultRootElement().getElement(ln-1).getStartOffset());;
// Remove the highlighting from the previously highlighted line
if (lastView.y != currentView.y)
component.repaint(0, lastView.y, component.getWidth(), lastView.height);
lastView = currentView;
catch(BadLocationException ble)
);
// Implement CaretListener
public void caretUpdate(CaretEvent e)
// resetHighlight();
// Implement MouseListener
public void mousePressed(MouseEvent e)
// resetHighlight();
public void mouseClicked(MouseEvent e)
public void mouseEntered(MouseEvent e)
public void mouseExited(MouseEvent e)
public void mouseReleased(MouseEvent e)
// Implement MouseMotionListener
public void mouseDragged(MouseEvent e)
// resetHighlight();
public void mouseMoved(MouseEvent e)
更新:
我更新了我的 LinePainter 文件如下。
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.event.*;
import javax.swing.text.*;
/*
* Track the movement of the Caret by painting a background line at the
* current caret position.
*/
public class LinePainter
implements Highlighter.HighlightPainter, CaretListener, MouseListener, MouseMotionListener
private JTextComponent component;
private Color color;
private Rectangle lastView;
/*
* The line color will be calculated automatically by attempting
* to make the current selection lighter by a factor of 1.2.
*
* @param component text component that requires background line painting
*/
public LinePainter(JTextComponent component)
this(component, null);
setLighter(component.getSelectionColor());
/*
* Manually control the line color
*
* @param component text component that requires background line painting
* @param color the color of the background line
*/
public LinePainter(JTextComponent component, Color color)
this.component = component;
setColor( color );
// Add listeners so we know when to change highlighting
component.addCaretListener( this );
component.addMouseListener( this );
component.addMouseMotionListener( this );
// Turn highlighting on by adding a dummy highlight
try
component.getHighlighter().addHighlight(0, 0, this);
catch(BadLocationException ble)
/*
* You can reset the line color at any time
*
* @param color the color of the background line
*/
public void setColor(Color color)
this.color = color;
/*
* Calculate the line color by making the selection color lighter
*
* @return the color of the background line
*/
public void setLighter(Color color)
int red = Math.min(255, (int)(color.getRed() * 1.2));
int green = Math.min(255, (int)(color.getGreen() * 1.2));
int blue = Math.min(255, (int)(color.getBlue() * 1.2));
setColor(new Color(red, green, blue));
public int ln=1,prev=1;
public void sl(int l) prev=ln; ln=l;
System.out.println("hii");
//resetHighlight();
// Paint the background highlight
public void paint(Graphics g, int p0, int p1, Shape bounds, JTextComponent c)
try
// System.out.println("calling paint");
// resetHighlight();
if(prev != ln)
Rectangle rect=c.modelToView((c).getDocument().getDefaultRootElement().getElement(prev-1).getStartOffset());
prev=ln;
System.out.println(rect.y+" " +c.getWidth()+" "+rect.height);
g.clearRect(0,rect.y,c.getWidth(),rect.height);
Rectangle r = c.modelToView((c).getDocument().getDefaultRootElement().getElement(ln-1).getStartOffset());
g.setColor( color );
// if(lastView != null)
// g.clearRect(0,lastView.y,c.getWidth(),lastView.height);
//
System.out.println(r.y+" " +c.getWidth()+" "+r.height);
g.fillRect(0, r.y, c.getWidth(), r.height);
if (lastView == null)
lastView = r;
catch(BadLocationException ble) System.out.println(ble);
/*
* Caret position has changed, remove the highlight
*/
private void resetHighlight()
System.out.println("reset");
// Use invokeLater to make sure updates to the Document are completed,
// otherwise Undo processing causes the modelToView method to loop.
SwingUtilities.invokeLater(new Runnable()
public void run()
try
System.out.println("prev line "+prev+" "+ln);
Rectangle currentView = component.modelToView(component.getDocument().getDefaultRootElement().getElement(prev-1).getStartOffset());
// Remove the highlighting from the previously highlighted line
if (lastView.y != currentView.y)
component.repaint(0, lastView.y, component.getWidth(), lastView.height);
lastView = currentView;
prev=ln;
catch(BadLocationException ble)
);
// Implement CaretListener
public void caretUpdate(CaretEvent e)
// resetHighlight();
// Implement MouseListener
public void mousePressed(MouseEvent e)
// resetHighlight();
public void mouseClicked(MouseEvent e)
public void mouseEntered(MouseEvent e)
public void mouseExited(MouseEvent e)
public void mouseReleased(MouseEvent e)
// Implement MouseMotionListener
public void mouseDragged(MouseEvent e)
// resetHighlight();
public void mouseMoved(MouseEvent e)
我仍然没有得到我想要的输出。调用 sl() 后突出显示不更新。如果有任何建议,请告诉我。谢谢.....
【问题讨论】:
【参考方案1】:您似乎从Line Painter 获得了代码。
该代码的关键是resetHighlight()
方法。每次更改插入符号位置时都会调用该方法,因此可以在新行处绘制突出显示。
您已注释掉对该方法的所有调用。
所以我认为你需要做两件事:
-
您的 sl(...) 方法需要调用 resetHighlight() 方法。
您需要修改resetHighlight()方法,以根据行号而不是插入符号位置来计算要重绘的Rectangle。
linePainter.sl(2);
x=sc.nextInt();
linePainter.sl(3);
不确定该代码的意义是什么。 LinePainter 一次只会绘制一条线,因此调用该方法两次将导致第 3 行被突出显示。
【讨论】:
@Hiatus_9,很高兴这个建议有所帮助。不要忘记“接受”答案,这样人们就知道问题已经解决了。 @camicrk 但无法获得正确的输出。仍然遇到同步问题。每当调用 sl(...) 方法时,如果我没有最大化或最小化窗口,则不会显示更新。请帮我。谢谢。 当我仔细查看原始代码时,代码的关键是 caretPosition 和该位置行高的 Rectangle。插入符号在paint() 和resetHighlight() 方法中被引用。所以我猜你需要更改这些方法以根据行号访问 Rectangle 。我看不出有任何理由保留前一个行号。我还建议您在更改要突出显示的行号时需要调用 resetHighlight() 方法。如果这不起作用,我不知道问题出在哪里。以上是关于在JTextPane java swing中填充直线矩形后无法与视图同步的主要内容,如果未能解决你的问题,请参考以下文章
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