我意识到,如果我没有包含行
jComboBox1.addItem("Cause Text Field To Override");
当我在JComboBox的文本字段中输入“A”时,“A”将显示在JComboBox的文本字段中。
但是,如果我包含addItem代码,JComboBox的文本字段将被覆盖。 (下边界线也消失了,不知道为什么)
我希望能够addItem和showPopup而不覆盖JCombBoBox文本字段中的内容。我可以知道怎么做吗?
package javaapplication5;
import java.awt.event.KeyAdapter;
import java.awt.event.KeyEvent;
/**
*
* @author yccheok
*/
public class NewJDialog extends javax.swing.JDialog {
/** Creates new form NewJDialog */
public NewJDialog(java.awt.Frame parent, boolean modal) {
super(parent, modal);
initComponents();
jComboBox1.getEditor().getEditorComponent().addKeyListener(new KeyAdapter() {
@Override
public void keyReleased(KeyEvent e) {
jComboBox1.addItem("Cause Text Field To Override");
jComboBox1.showPopup();
}
});
}
/** This method is called from within the constructor to
* initialize the form.
* WARNING: Do NOT modify this code. The content of this method is
* always regenerated by the Form Editor.
*/
@SuppressWarnings("unchecked")
// <editor-fold defaultstate="collapsed" desc="Generated Code">
private void initComponents() {
jComboBox1 = new javax.swing.JComboBox();
setDefaultCloseOperation(javax.swing.WindowConstants.DISPOSE_ON_CLOSE);
jComboBox1.setEditable(true);
jComboBox1.setModel(new javax.swing.DefaultComboBoxModel(new String[] { "Hello", "World", "Bye" }));
javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane());
getContentPane().setLayout(layout);
layout.setHorizontalGroup(
layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(layout.createSequentialGroup()
.addGap(124, 124, 124)
.addComponent(jComboBox1, javax.swing.GroupLayout.PREFERRED_SIZE, 184, javax.swing.GroupLayout.PREFERRED_SIZE)
.addContainerGap(92, Short.MAX_VALUE))
);
layout.setVerticalGroup(
layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(layout.createSequentialGroup()
.addGap(76, 76, 76)
.addComponent(jComboBox1, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
.addContainerGap(204, Short.MAX_VALUE))
);
pack();
}// </editor-fold>
/**
* @param args the command line arguments
*/
public static void main(String args[]) {
java.awt.EventQueue.invokeLater(new Runnable() {
public void run() {
NewJDialog dialog = new NewJDialog(new javax.swing.JFrame(), true);
dialog.addWindowListener(new java.awt.event.WindowAdapter() {
public void windowClosing(java.awt.event.WindowEvent e) {
System.exit(0);
}
});
dialog.setVisible(true);
}
});
}
// Variables declaration - do not modify
private javax.swing.JComboBox jComboBox1;
// End of variables declaration
}
答案 0 :(得分:1)
自从我完成Swing以来已经很长时间了,但我怀疑当你执行AddItem时会导致一个contentChanged回调,因为组合框是ListDataListener,并且基于该组合框重新设置选择项目到其模型中的第一项。
我建议你看看JComboBox在ListDataListener的实现中做了什么,然后调试一下。
然而,看起来你正在尝试做的事情与摇摆的自然摆动有点相反 - 即键入一个键通过添加到模型来改变模型中的内容。
不要在组合框上使用keyEvents,最好将模型添加到模型中,然后以您需要的方式操作结果。