聚焦时使JSpinner选择文本

您面临的许多问题与在焦点事件（以及其他一些状态事件）发生后，旋转器如何验证旋转器中的任何值有关，这将避免突出显示。

MacOS甚至更糟。

我最终要做的是启动一个

Thread

SwingUtilities.invokeLater

用示例更新

import java.awt.Component;import java.awt.EventQueue;import java.awt.GridBagLayout;import java.awt.event.FocusAdapter;import java.awt.event.FocusEvent;import java.util.ArrayList;import java.util.Collections;import java.util.List;import javax.swing.JButton;import javax.swing.JComponent;import javax.swing.Jframe;import javax.swing.JSpinner;import javax.swing.SpinnerNumberModel;import javax.swing.SwingUtilities;import javax.swing.UIManager;import javax.swing.UnsupportedLookAndFeelException;import javax.swing.text.JTextComponent;public class AutoFocusSpinner {    public static void main(String[] args) {        new AutoFocusSpinner();    }    public static final SelectonFocusGainedHandler SHARED_INSTANCE = new SelectonFocusGainedHandler();    public AutoFocusSpinner() {        EventQueue.invokeLater(new Runnable() { @Override public void run() {     try {         UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());     } catch (ClassNotFoundException ex) {     } catch (InstantiationException ex) {     } catch (IllegalAccessException ex) {     } catch (UnsupportedLookAndFeelException ex) {     }     JSpinner spinner = new JSpinner(new SpinnerNumberModel(1, 0, 100, 1));     installFocusListener(spinner);     Jframe frame = new Jframe("Test");     frame.setDefaultCloseOperation(Jframe.EXIT_ON_CLOSE);     frame.setLayout(new GridBagLayout());     frame.add(spinner);     frame.add(new JButton("Here for testing"));     frame.pack();     frame.setLocationRelativeTo(null);     frame.setVisible(true); }        });    }    public void installFocusListener(JSpinner spinner) {        JComponent spinnerEditor = spinner.getEditor();        if (spinnerEditor != null) { // This is me spending a few days trying to make this work and  // eventually throwing a hissy fit and just grabbing all the  // JTextComponent components contained within the editor.... List<JTextComponent> lstChildren = findAllChildren(spinner, JTextComponent.class); if (lstChildren != null && lstChildren.size() > 0) {     JTextComponent editor = lstChildren.get(0);     editor.addFocusListener(SHARED_INSTANCE); }        }    }    public static <T extends Component> List<T> findAllChildren(JComponent component, Class<T> clazz) {        List<T> lstChildren = new ArrayList<T>(5);        for (Component comp : component.getComponents()) { if (clazz.isInstance(comp)) {     lstChildren.add((T) comp); } else if (comp instanceof JComponent) {     lstChildren.addAll(findAllChildren((JComponent) comp, clazz)); }        }        return Collections.unmodifiableList(lstChildren);    }    public static class SelectonFocusGainedHandler extends FocusAdapter {        @Override        public void focusGained(FocusEvent e) { Component comp = e.getComponent(); if (comp instanceof JTextComponent) {     final JTextComponent textComponent = (JTextComponent) comp;     new Thread(new Runnable() {         @Override         public void run() {  try {      Thread.sleep(25);  } catch (InterruptedException ex) {  }  SwingUtilities.invokeLater(new Runnable() {      @Override      public void run() {          textComponent.selectAll();      }  });         }     }).start(); }         } }}

Now, right about now, I’m praying for some really nice, simple, undocumented
property that we can set that will mean we don’t need to do all this :P