下面2个类,为什么JTextArea里面写不了东西。请高手解答。
----------------------------
package plc;
public class MyClass {
public MyClass(){
}
public void setText(){
MyFrame mf = new MyFrame();
mf.setArea("There is ShangHai");
}
public static void main(String[] args)
{
}
}-------------------------
package plc;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JScrollPane;
import javax.swing.JTextArea;
import javax.swing.SwingUtilities;
import javax.swing.UIManager;
import org.dyno.visual.swing.layouts.Constraints;
import org.dyno.visual.swing.layouts.GroupLayout;
import org.dyno.visual.swing.layouts.Leading;
//VS4E -- DO NOT REMOVE THIS LINE!
public class MyFrame extends JFrame {
private static final long serialVersionUID = 1L;
private JButton jButtonOK;
private JTextArea jTextAreaMessage;
private JScrollPane jScrollPaneMessage;
private static final String PREFERRED_LOOK_AND_FEEL = "javax.swing.plaf.metal.MetalLookAndFeel";
public MyFrame() {
initComponents();
}
private void initComponents() {
setLayout(new GroupLayout());
add(getJScrollPaneMessage(), new Constraints(new Leading(58, 189, 10, 10), new Leading(73, 80, 10, 10)));
add(getJButtonOK(), new Constraints(new Leading(105, 87, 10, 10), new Leading(24, 10, 10)));
setSize(320, 240);
}
private JButton getJButtonOK() {
if (jButtonOK == null) {
jButtonOK = new JButton();
jButtonOK.setText("OK");
jButtonOK.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent event) {
jButtonOKActionActionPerformed(event);
}
});
}
return jButtonOK;
}
private JScrollPane getJScrollPaneMessage() {
if (jScrollPaneMessage == null) {
jScrollPaneMessage = new JScrollPane();
jScrollPaneMessage.setViewportView(getJTextArea0());
}
return jScrollPaneMessage;
}
private JTextArea getJTextArea0() {
if (jTextAreaMessage == null) {
jTextAreaMessage = new JTextArea();
jTextAreaMessage.setText("jTextArea0");
}
return jTextAreaMessage;
}
private JButton getJButton0() {
if (jButtonOK == null) {
jButtonOK = new JButton();
jButtonOK.setText("OK");
}
return jButtonOK;
}
private static void installLnF() {
try {
String lnfClassname = PREFERRED_LOOK_AND_FEEL;
if (lnfClassname == null)
lnfClassname = UIManager.getCrossPlatformLookAndFeelClassName();
UIManager.setLookAndFeel(lnfClassname);
} catch (Exception e) {
System.err.println("Cannot install " + PREFERRED_LOOK_AND_FEEL
+ " on this platform:" + e.getMessage());
}
}
/**
* Main entry of the class.
* Note: This class is only created so that you can easily preview the result at runtime.
* It is not expected to be managed by the designer.
* You can modify it as you like.
*/
public static void main(String[] args) {
installLnF();
SwingUtilities.invokeLater(new Runnable() {
@Override
public void run() {
MyFrame frame = new MyFrame();
frame.setDefaultCloseOperation(MyFrame.EXIT_ON_CLOSE);
frame.setTitle("MyFrame");
frame.getContentPane().setPreferredSize(frame.getSize());
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
private void jButtonOKActionActionPerformed(ActionEvent event) {
//jTextAreaMessage.append("There is Beijing"+"\r\n");
//jTextAreaMessage.paintImmediately(jTextAreaMessage.getBounds());
MyClass mc=new MyClass();
mc.setText();
}
public void setArea(String str){
jTextAreaMessage.append(str+"\r\n");
jTextAreaMessage.paintImmediately(jTextAreaMessage.getBounds());
System.out.println("printed:"+str);
}
}
----------------------------
package plc;
public class MyClass {
public MyClass(){
}
public void setText(){
MyFrame mf = new MyFrame();
mf.setArea("There is ShangHai");
}
public static void main(String[] args)
{
}
}-------------------------
package plc;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JScrollPane;
import javax.swing.JTextArea;
import javax.swing.SwingUtilities;
import javax.swing.UIManager;
import org.dyno.visual.swing.layouts.Constraints;
import org.dyno.visual.swing.layouts.GroupLayout;
import org.dyno.visual.swing.layouts.Leading;
//VS4E -- DO NOT REMOVE THIS LINE!
public class MyFrame extends JFrame {
private static final long serialVersionUID = 1L;
private JButton jButtonOK;
private JTextArea jTextAreaMessage;
private JScrollPane jScrollPaneMessage;
private static final String PREFERRED_LOOK_AND_FEEL = "javax.swing.plaf.metal.MetalLookAndFeel";
public MyFrame() {
initComponents();
}
private void initComponents() {
setLayout(new GroupLayout());
add(getJScrollPaneMessage(), new Constraints(new Leading(58, 189, 10, 10), new Leading(73, 80, 10, 10)));
add(getJButtonOK(), new Constraints(new Leading(105, 87, 10, 10), new Leading(24, 10, 10)));
setSize(320, 240);
}
private JButton getJButtonOK() {
if (jButtonOK == null) {
jButtonOK = new JButton();
jButtonOK.setText("OK");
jButtonOK.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent event) {
jButtonOKActionActionPerformed(event);
}
});
}
return jButtonOK;
}
private JScrollPane getJScrollPaneMessage() {
if (jScrollPaneMessage == null) {
jScrollPaneMessage = new JScrollPane();
jScrollPaneMessage.setViewportView(getJTextArea0());
}
return jScrollPaneMessage;
}
private JTextArea getJTextArea0() {
if (jTextAreaMessage == null) {
jTextAreaMessage = new JTextArea();
jTextAreaMessage.setText("jTextArea0");
}
return jTextAreaMessage;
}
private JButton getJButton0() {
if (jButtonOK == null) {
jButtonOK = new JButton();
jButtonOK.setText("OK");
}
return jButtonOK;
}
private static void installLnF() {
try {
String lnfClassname = PREFERRED_LOOK_AND_FEEL;
if (lnfClassname == null)
lnfClassname = UIManager.getCrossPlatformLookAndFeelClassName();
UIManager.setLookAndFeel(lnfClassname);
} catch (Exception e) {
System.err.println("Cannot install " + PREFERRED_LOOK_AND_FEEL
+ " on this platform:" + e.getMessage());
}
}
/**
* Main entry of the class.
* Note: This class is only created so that you can easily preview the result at runtime.
* It is not expected to be managed by the designer.
* You can modify it as you like.
*/
public static void main(String[] args) {
installLnF();
SwingUtilities.invokeLater(new Runnable() {
@Override
public void run() {
MyFrame frame = new MyFrame();
frame.setDefaultCloseOperation(MyFrame.EXIT_ON_CLOSE);
frame.setTitle("MyFrame");
frame.getContentPane().setPreferredSize(frame.getSize());
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
private void jButtonOKActionActionPerformed(ActionEvent event) {
//jTextAreaMessage.append("There is Beijing"+"\r\n");
//jTextAreaMessage.paintImmediately(jTextAreaMessage.getBounds());
MyClass mc=new MyClass();
mc.setText();
}
public void setArea(String str){
jTextAreaMessage.append(str+"\r\n");
jTextAreaMessage.paintImmediately(jTextAreaMessage.getBounds());
System.out.println("printed:"+str);
}
}
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