java – 在复选框的itemStatechanged事件上显示文本字段

如何在Swing中的复选框的itemStatechanged事件中显示文本字段？

我正在尝试使用复选框和文本字段创建框架.我希望仅在选中复选框时才显示文本字段.因此,当我初始化组件时,我将textfield.setvisible设置为false,并且为复选框添加了addItemListener并调用了itemStateChanged事件,并且选中了复选框,我将setVisible方法设置为true.

我的SSCCE看起来像：

package ui;
public class Evaluator extends javax.swing.JFrame {
public Evaluator() {
    initComponents();
}
private void initComponents() {

    jCheckBox1 = new javax.swing.JCheckBox();
    jTextField1 = new javax.swing.JTextField();
    jTextField1.setVisible(false);
    setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);
    setPreferredSize(new java.awt.Dimension(800, 800));
    jCheckBox1.setFont(new java.awt.Font("Tahoma", 0, 14));
    jCheckBox1.setText("Properties");
    jCheckBox1.addItemListener(new java.awt.event.ItemListener() {
        public void itemStateChanged(java.awt.event.ItemEvent evt) {
            jCheckBox1ItemStateChanged(evt);
        }
    });
    jTextField1.setFont(new java.awt.Font("Tahoma", 0, 14));
    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(jCheckBox1)
            .addGap(41, 41, 41)
            .addComponent(jTextField1, javax.swing.GroupLayout.PREFERRED_SIZE, 109, javax.swing.GroupLayout.PREFERRED_SIZE)
            .addContainerGap(155, Short.MAX_VALUE))
    );
    layout.setVerticalGroup(
        layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
        .addGroup(javax.swing.GroupLayout.Alignment.TRAILING, layout.createSequentialGroup()
            .addContainerGap(229, Short.MAX_VALUE)
            .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
                .addComponent(jCheckBox1)
                .addComponent(jTextField1, javax.swing.GroupLayout.PREFERRED_SIZE, 37, javax.swing.GroupLayout.PREFERRED_SIZE))
            .addGap(34, 34, 34))
    );
    pack();
}
private void jCheckBox1ItemStateChanged(java.awt.event.ItemEvent evt) {                                            
    // TODO add your handling code here:
     if(evt.getStateChange()== java.awt.event.ItemEvent.SELECTED){
        jTextField1.setVisible(true);

   }
}                                           
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(Evaluator.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
    } catch (InstantiationException ex) {
        java.util.logging.Logger.getLogger(Evaluator.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
    } catch (IllegalAccessException ex) {
        java.util.logging.Logger.getLogger(Evaluator.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
    } catch (javax.swing.UnsupportedLookAndFeelException ex) {
        java.util.logging.Logger.getLogger(Evaluator.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
    }
    java.awt.EventQueue.invokeLater(new Runnable() {
        public void run() {
            new Evaluator().setVisible(true);
        }
    });
}
private javax.swing.JCheckBox jCheckBox1;
private javax.swing.JTextField jTextField1;                
}

解决方法:

基本上,您需要使框架(或父容器)无效以强制它重新布局

private void jCheckBox2ItemStateChanged(java.awt.event.ItemEvent evt) {
    jTextField1.setVisible(jCheckBox2.isSelected());
    invalidate();
    validate();
}

更新

我还建议您避免将整个UI添加到顶级容器中,而是使用JPanel作为基础组件并围绕它们构建UI.准备好后,只需将基本面板添加到您需要的顶级容器中.

标签：jcheckbox,java,swing,jtextfield,visibility
来源： https://codeday.me/bug/20190723/1509445.html