我正在构建一个应用程序,它将标签放在用户点击面板(jpanel2)的位置,并允许它移动放置的标签。
我可以成功放置标签,但我无法移动任何标签。事实上,当我尝试拖动标签时,它会在我的所有尝试中消失。 我也尝试在jPanel2和JFrame中调用重绘,但仍然没有成功。
JPanel 2没有布局(免费设计),因为想要将标签准确放置在鼠标点击的位置。
更新
以下是发生问题的最小示例。 我无法减少面板数量,因为我需要在屏幕上放置更多控件(例如jtable,菜单和工具栏)。
public class Example extends javax.swing.JFrame {
static int count = 0;
public Example() {
initComponents();
}
@SuppressWarnings("unchecked")
private void initComponents() {
jPanel1 = new javax.swing.JPanel();
jPanel2 = new javax.swing.JPanel();
jPanel3 = new javax.swing.JPanel();
jLabel1 = new javax.swing.JLabel();
setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);
setPreferredSize(new java.awt.Dimension(600, 600));
jPanel2.addMouseListener(new java.awt.event.MouseAdapter() {
public void mouseClicked(java.awt.event.MouseEvent evt) {
jPanel2MouseClicked(evt);
}
});
jPanel3.setMinimumSize(new java.awt.Dimension(0, 0));
jPanel3.setLayout(new java.awt.BorderLayout());
jPanel3.add(jLabel1, java.awt.BorderLayout.CENTER);
javax.swing.GroupLayout jPanel2Layout = new javax.swing.GroupLayout(jPanel2);
jPanel2.setLayout(jPanel2Layout);
jPanel2Layout.setHorizontalGroup(
jPanel2Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addComponent(jPanel3, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
);
jPanel2Layout.setVerticalGroup(
jPanel2Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addComponent(jPanel3, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
);
javax.swing.GroupLayout jPanel1Layout = new javax.swing.GroupLayout(jPanel1);
jPanel1.setLayout(jPanel1Layout);
jPanel1Layout.setHorizontalGroup(
jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addComponent(jPanel2, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
);
jPanel1Layout.setVerticalGroup(
jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(jPanel1Layout.createSequentialGroup()
.addComponent(jPanel2, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
.addContainerGap())
);
getContentPane().add(jPanel1, java.awt.BorderLayout.CENTER);
pack();
}// </editor-fold>
private void jPanel2MouseClicked(java.awt.event.MouseEvent evt) {
count++;
addAnnotation(String.valueOf(count), evt.getX(), evt.getY());
}
private void addAnnotation(String labelStr, int x, int y) {
final JLabel label = new JLabel(labelStr);
jPanel2.add(label);
label.setLocation(x, y);
System.out.println("Adding to " + x + " " + y);
label.setSize(20, 20);
label.setBackground(Color.WHITE);
label.setOpaque(true);
label.setBorder(new LineBorder(Color.BLACK, 1, false));
label.setHorizontalAlignment(SwingConstants.CENTER);
label.setVisible(true);
label.setForeground(Color.BLACK);
label.addMouseMotionListener(new MouseMotionListener() {
@Override
public void mouseDragged(MouseEvent e) {
Component c = e.getComponent();
int moveToX = c.getX() + e.getX();
int moveToY = c.getY() + e.getY();
c.setLocation(moveToX, moveToY);
System.out.println("Moving to " + moveToX + " " + moveToY);
}
@Override
public void mouseMoved(MouseEvent e) {
}
});
}
/**
* @param args the command line arguments
*/
public static void main(String args[]) {
/* Set the Nimbus look and feel */
//<editor-fold defaultstate="collapsed" desc=" Look and feel setting code (optional) ">
/* If Nimbus (introduced in Java SE 6) is not available, stay with the default look and feel.
* For details see http://download.oracle.com/javase/tutorial/uiswing/lookandfeel/plaf.html
*/
try {
for (javax.swing.UIManager.LookAndFeelInfo info : javax.swing.UIManager.getInstalledLookAndFeels()) {
if ("Nimbus".equals(info.getName())) {
javax.swing.UIManager.setLookAndFeel(info.getClassName());
break;
}
}
} catch (ClassNotFoundException ex) {
java.util.logging.Logger.getLogger(Example.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (InstantiationException ex) {
java.util.logging.Logger.getLogger(Example.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (IllegalAccessException ex) {
java.util.logging.Logger.getLogger(Example.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (javax.swing.UnsupportedLookAndFeelException ex) {
java.util.logging.Logger.getLogger(Example.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
}
//</editor-fold>
/* Create and display the form */
java.awt.EventQueue.invokeLater(new Runnable() {
public void run() {
new Example().setVisible(true);
}
});
}
// Variables declaration - do not modify
private javax.swing.JLabel jLabel1;
private javax.swing.JPanel jPanel1;
private javax.swing.JPanel jPanel2;
private javax.swing.JPanel jPanel3;
// End of variables declaration
}
答案 0 :(得分:3)
如果您要使用GUI Builder制作程序,您需要做的是将面板的布局设置为null。然后,当您向面板添加标签时,需要为它们设置边界。下面是一个如何实现这一目标的例子。
JPanel
。我把它扩展到了框架的大小。JLabel
然后jPanel
和revalidate()
repaint()
添加了jPanel1
。MouseMotionListener
这是我添加的唯一代码。全部在构造函数中。除了pX
和pY
变量作为类成员
int pX, pY;
public NewJFrame() {
initComponents();
jPanel1.setLayout(null);
final JLabel label = new JLabel();
label.setHorizontalAlignment(JLabel.CENTER);
label.setBounds(50, 50, 50, 50);
label.setBorder(new LineBorder(Color.black, 3));
label.setText("Hello");
label.addMouseMotionListener(new MouseMotionAdapter(){
public void mouseDragged(MouseEvent me) {
label.setLocation(label.getLocation().x + me.getX() - pX,
label.getLocation().y + me.getY() - pY);
jPanel1.revalidate();
jPanel1.repaint();
}
});
label.addMouseListener(new MouseAdapter() {
public void mousePressed(MouseEvent me) {
// Get x,y and store them
pX = me.getX();
pY = me.getY();
}
});
jPanel1.add(label);
jPanel1.revalidate();
jPanel1.repaint();
}
这是完整的程序
import java.awt.Color;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.awt.event.MouseMotionAdapter;
import javax.swing.JLabel;
import javax.swing.border.LineBorder;
public class NewJFrame extends javax.swing.JFrame {
int pX, pY;
public NewJFrame() {
initComponents();
jPanel1.setLayout(null);
final JLabel label = new JLabel();
label.setHorizontalAlignment(JLabel.CENTER);
label.setBounds(50, 50, 50, 50);
label.setBorder(new LineBorder(Color.black, 3));
label.setText("Hello");
label.addMouseMotionListener(new MouseMotionAdapter(){
public void mouseDragged(MouseEvent me) {
label.setLocation(label.getLocation().x + me.getX() - pX,
label.getLocation().y + me.getY() - pY);
jPanel1.revalidate();
jPanel1.repaint();
}
});
label.addMouseListener(new MouseAdapter() {
public void mousePressed(MouseEvent me) {
// Get x,y and store them
pX = me.getX();
pY = me.getY();
}
});
jPanel1.add(label);
jPanel1.revalidate();
jPanel1.repaint();
}
@SuppressWarnings("unchecked")
// <editor-fold defaultstate="collapsed" desc="Generated Code">
private void initComponents() {
jPanel1 = new javax.swing.JPanel();
setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);
javax.swing.GroupLayout jPanel1Layout = new javax.swing.GroupLayout(jPanel1);
jPanel1.setLayout(jPanel1Layout);
jPanel1Layout.setHorizontalGroup(
jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGap(0, 388, Short.MAX_VALUE)
);
jPanel1Layout.setVerticalGroup(
jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGap(0, 288, Short.MAX_VALUE)
);
javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane());
getContentPane().setLayout(layout);
layout.setHorizontalGroup(
layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(layout.createSequentialGroup()
.addContainerGap()
.addComponent(jPanel1, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
.addContainerGap())
);
layout.setVerticalGroup(
layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(javax.swing.GroupLayout.Alignment.TRAILING, layout.createSequentialGroup()
.addContainerGap()
.addComponent(jPanel1, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
.addContainerGap())
);
pack();
}// </editor-fold>
public static void main(String args[]) {
try {
for (javax.swing.UIManager.LookAndFeelInfo info : javax.swing.UIManager.getInstalledLookAndFeels()) {
if ("Nimbus".equals(info.getName())) {
javax.swing.UIManager.setLookAndFeel(info.getClassName());
break;
}
}
} catch (ClassNotFoundException ex) {
java.util.logging.Logger.getLogger(NewJFrame.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (InstantiationException ex) {
java.util.logging.Logger.getLogger(NewJFrame.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (IllegalAccessException ex) {
java.util.logging.Logger.getLogger(NewJFrame.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (javax.swing.UnsupportedLookAndFeelException ex) {
java.util.logging.Logger.getLogger(NewJFrame.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
}
//</editor-fold>
/* Create and display the form */
java.awt.EventQueue.invokeLater(new Runnable() {
public void run() {
new NewJFrame().setVisible(true);
}
});
}
// Variables declaration - do not modify
private javax.swing.JPanel jPanel1;
// End of variables declaration
}
答案 1 :(得分:0)
我改变了你的代码。
jpanel2顶部有一个面板(你用来添加jlabels的面板)。
我在initComponents()之后清除了jpanel2
jpanel2.removeAll();
它有效。
/* * To change this template, choose Tools | Templates * and open the template in the editor. */ package javaapplication16; import java.awt.Color; import java.awt.Component; import java.awt.event.MouseEvent; import java.awt.event.MouseListener; import java.awt.event.MouseMotionListener; import javax.swing.JLabel; import javax.swing.SwingConstants; import javax.swing.SwingUtilities; import javax.swing.border.LineBorder; public class E extends javax.swing.JFrame { static int count = 0; public E() { initComponents(); //jPanel2.setBackground(Color.YELLOW);; jPanel2.removeAll();; } @SuppressWarnings("unchecked") private void initComponents() { jPanel1 = new javax.swing.JPanel(); jPanel2 = new javax.swing.JPanel(); jPanel3 = new javax.swing.JPanel(); jLabel1 = new javax.swing.JLabel(); setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE); setPreferredSize(new java.awt.Dimension(600, 600)); jPanel2.addMouseListener(new java.awt.event.MouseAdapter() { public void mouseClicked(java.awt.event.MouseEvent evt) { jPanel2MouseClicked(evt); } }); jPanel3.setMinimumSize(new java.awt.Dimension(0, 0)); jPanel3.setLayout(new java.awt.BorderLayout()); jPanel3.add(jLabel1, java.awt.BorderLayout.CENTER); javax.swing.GroupLayout jPanel2Layout = new javax.swing.GroupLayout(jPanel2); jPanel2.setLayout(jPanel2Layout); jPanel2Layout.setHorizontalGroup( jPanel2Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING) .addComponent(jPanel3, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE) ); jPanel2Layout.setVerticalGroup( jPanel2Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING) .addComponent(jPanel3, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE) ); javax.swing.GroupLayout jPanel1Layout = new javax.swing.GroupLayout(jPanel1); jPanel1.setLayout(jPanel1Layout); jPanel1Layout.setHorizontalGroup( jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING) .addComponent(jPanel2, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE) ); jPanel1Layout.setVerticalGroup( jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING) .addGroup(jPanel1Layout.createSequentialGroup() .addComponent(jPanel2, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE) .addContainerGap()) ); getContentPane().add(jPanel1, java.awt.BorderLayout.CENTER); pack(); }// private void jPanel2MouseClicked(java.awt.event.MouseEvent evt) { count++; addAnnotation(String.valueOf(count), evt.getX(), evt.getY()); } private void addAnnotation(String labelStr, int x, int y) { final JLabel label = new JLabel(labelStr); jPanel2.add(label); label.setLocation(x, y); System.out.println("Adding to " + x + " " + y); label.setSize(200, 200); label.setBackground(Color.WHITE); label.setOpaque(true); label.setBorder(new LineBorder(Color.BLACK, 1, false)); label.setHorizontalAlignment(SwingConstants.CENTER); label.setVisible(true); label.setForeground(Color.BLACK); label.addMouseMotionListener(new MouseMotionListener() { @Override public void mouseDragged(MouseEvent e) { Component c = e.getComponent(); int moveToX = e.getX() + c.getX(); int moveToY = e.getY() + c.getY(); c.setLocation(moveToX, moveToY); c.repaint(); } @Override public void mouseMoved(MouseEvent e) { //Component c = e.getComponent(); } }); } /** * @param args the command line arguments */ public static void main(String args[]) { /* Set the Nimbus look and feel */ // /* If Nimbus (introduced in Java SE 6) is not available, stay with the default look and feel. * For details see http://download.oracle.com/javase/tutorial/uiswing/lookandfeel/plaf.html */ try { for (javax.swing.UIManager.LookAndFeelInfo info : javax.swing.UIManager.getInstalledLookAndFeels()) { if ("Nimbus".equals(info.getName())) { javax.swing.UIManager.setLookAndFeel(info.getClassName()); break; } } } catch (ClassNotFoundException ex) { java.util.logging.Logger.getLogger(E.class.getName()).log(java.util.logging.Level.SEVERE, null, ex); } catch (InstantiationException ex) { java.util.logging.Logger.getLogger(E.class.getName()).log(java.util.logging.Level.SEVERE, null, ex); } catch (IllegalAccessException ex) { java.util.logging.Logger.getLogger(E.class.getName()).log(java.util.logging.Level.SEVERE, null, ex); } catch (javax.swing.UnsupportedLookAndFeelException ex) { java.util.logging.Logger.getLogger(E.class.getName()).log(java.util.logging.Level.SEVERE, null, ex); } // /* Create and display the form */ java.awt.EventQueue.invokeLater(new Runnable() { public void run() { new E().setVisible(true); } }); } // Variables declaration - do not modify private javax.swing.JLabel jLabel1; private javax.swing.JPanel jPanel1; private javax.swing.JPanel jPanel2; private javax.swing.JPanel jPanel3; // End of variables declaration }