blocks|key|1886282|text|Swings的setEnabled函数没有什么特别之处，你可以像其他函数一样覆盖它。在代码中调用someToggleLabel.setEnabled(false)显然不会禁用JLabel+(根据基本的Java语义)。一定是别的什么地方出了问题。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1886283|如果您希望能够禁用组件(因为您说您有另一种显示它的方式)，我建议您不要“禁用”swing提供的禁用组件的机制，而是尝试更改一些外观和感觉。|1886284|例如，您是否考虑过使用JLabel.setDisabledIcon|1886285|你可能会发现有用的与相关的问题：|BOLD|1886286|1886287|How+can+I+replicate+disabled+appearance+for+a+JCheckBox?|unordered-list-item|1886288|In+Swing,+is+there+a+property+to+set+a+JList+disabled+foreground+color?|1886289|How+to+change+the+look+of+a+disabled+JButton+in+java|1886290|How+to+change+the+text+color+of+a+disabled+button+to+black+in+Java+(NetBeans)?|1886291|1886292|entityMap|0|LINK|mutability|MUTABLE|url|http://docs.oracle.com/javase/1.4.2/docs/api/javax/swing/JLabel.html#setDisabledIcon%2528javax.swing.Icon%2529|1|https://stackoverflow.com/questions/3130650/how-can-i-replicate-disabled-appearance-for-a-jcheckbox|2|https://stackoverflow.com/questions/2276691/in-swing-is-there-a-property-to-set-a-jlist-disabled-foreground-color|3|https://stackoverflow.com/questions/1590764/how-to-change-the-look-of-a-disabled-jbutton-in-java|4|https://stackoverflow.com/questions/4826124/how-to-change-the-text-color-of-a-disabled-button-to-black-in-java-netbeans^0|7|A|1C|X|0|0|B|M|B|M|0|0|A|6|0|0|0|1K|1|0|0|1Z|2|0|0|1G|3|0|0|26|4|0|0^^$0|@$1|2|3|4|5|6|7|1D|8|@$9|1E|A|1F|B|C]|$9|1G|A|1H|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|1I|8|@]|D|@]|E|$]]|$1|H|3|I|5|6|7|1J|8|@$9|1K|A|1L|B|C]]|D|@$9|1M|A|1N|1|1O]]|E|$]]|$1|J|3|K|5|6|7|1P|8|@$9|1Q|A|1R|B|L]]|D|@]|E|$]]|$1|M|3|-4|5|6|7|1S|8|@]|D|@]|E|$]]|$1|N|3|O|5|P|7|1T|8|@]|D|@$9|1U|A|1V|1|1W]]|E|$]]|$1|Q|3|R|5|P|7|1X|8|@]|D|@$9|1Y|A|1Z|1|20]]|E|$]]|$1|S|3|T|5|P|7|21|8|@]|D|@$9|22|A|23|1|24]]|E|$]]|$1|U|3|V|5|P|7|25|8|@]|D|@$9|26|A|27|1|28]]|E|$]]|$1|W|3|-4|5|6|7|29|8|@]|D|@]|E|$]]|$1|X|3|-4|5|6|7|2A|8|@]|D|@]|E|$]]]|Y|$Z|$5|10|11|12|E|$13|14]]|15|$5|10|11|12|E|$13|16]]|17|$5|10|11|12|E|$13|18]]|19|$5|10|11|12|E|$13|1A]]|1B|$5|10|11|12|E|$13|1C]]]]

There's nothing special with Swings <code>setEnabled</code> function, you can override it as any other function. Invoking <code>someToggleLabel.setEnabled(false)</code> in your code will obviously not disable the JLabel (by fundamental Java semantics). Something else must be wrong.

If you want to be able to disable the component (as it seems since you say you have another way of showing it) I suggest you don't "disable" the mechanism swing provides for disabling a component but instead try to change the look and feel some how.

Have you for instance considered using <a href="http://docs.oracle.com/javase/1.4.2/docs/api/javax/swing/JLabel.html#setDisabledIcon%28javax.swing.Icon%29" rel="nofollow noreferrer"><code>JLabel.setDisabledIcon</code></a>?

Related questions which you might find useful:

<ul>
<li><a href="https://stackoverflow.com/questions/3130650/how-can-i-replicate-disabled-appearance-for-a-jcheckbox">How can I replicate disabled appearance for a JCheckBox?</a></li>
<li><a href="https://stackoverflow.com/questions/2276691/in-swing-is-there-a-property-to-set-a-jlist-disabled-foreground-color">In Swing, is there a property to set a JList disabled foreground color?</a></li>
<li><a href="https://stackoverflow.com/questions/1590764/how-to-change-the-look-of-a-disabled-jbutton-in-java">How to change the look of a disabled JButton in java</a></li>
<li><a href="https://stackoverflow.com/questions/4826124/how-to-change-the-text-color-of-a-disabled-button-to-black-in-java-netbeans">How to change the text color of a disabled button to black in Java (NetBeans)?</a></li>
</ul>

blocks|key|869759|text|我不知道你为什么这么想，例如，以这个程序为例：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|869760|package+so;

import+java.awt.Color;
import+java.util.Arrays;

import+javax.swing.Icon;
import+javax.swing.JFrame;
import+javax.swing.JLabel;
import+javax.swing.JPanel;
import+javax.swing.SwingUtilities;


public+class+Example+{

++++public+static+void+main(String[]+args)+{
++++++++SwingUtilities.invokeLater(new+Runnable()+{
++++++++++++@Override
++++++++++++public+void+run()+{
++++++++++++++++JFrame+f+=+new+JFrame();
++++++++++++++++JPanel+p+=+new+JPanel();
++++++++++++++++ToggleLabel+tl+=+new+ToggleLabel("hello");
++++++++++++++++p.add(tl);
++++++++++++++++tl.setBackground(Color.GREEN);
++++++++++++++++tl.setEnabled(false);
++++++++++++++++f.add(p);
++++++++++++++++f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
++++++++++++++++f.pack();
++++++++++++++++f.setVisible(true);+++++
++++++++++++}
++++++++});
++++}

++++private+static+class+ToggleLabel+extends+JLabel+{

++++++++private+boolean+toggle;

++++++++public+ToggleLabel(String+s)+{
++++++++++++super(s);
++++++++}

++++++++@Override
++++++++public+void+setEnabled(boolean+toggle)+{
++++++++++++this.toggle+=+toggle;
++++++++++++System.out.println("I+am+used");

++++++++}
++++++++@Override
++++++++public+boolean+isEnabled()+{
++++++++++++return+toggle;
++++++++}
++++}

}|code-block|syntax|javascript|869761|正如您所看到的，"I+is+used“被打印出来，程序在运行时看起来像这样：|869762|​|869763|📷|atomic|offset|length|869764|869765|entityMap|0|IMAGE|mutability|IMMUTABLE|imageUrl|https://ask.qcloudimg.com/http-save/yehe-900000/e79524fd32eb04f0b8076a9b644b61c2.png|imageAlt^0|0|0|0|0|0|1|0|0|0^^$0|@$1|2|3|4|5|6|7|Z|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|10|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|11|8|@]|9|@]|A|$]]|$1|I|3|J|5|6|7|12|8|@]|9|@]|A|$]]|$1|K|3|L|5|M|7|13|8|@]|9|@$N|14|O|15|1|16]]|A|$]]|$1|P|3|J|5|6|7|17|8|@]|9|@]|A|$]]|$1|Q|3|-4|5|6|7|18|8|@]|9|@]|A|$]]]|R|$S|$5|T|U|V|A|$W|X|Y|-4]]]]

I don't know why you think so, for example, take this program:

<pre><code>package so;

import java.awt.Color;
import java.util.Arrays;

import javax.swing.Icon;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.SwingUtilities;


public class Example {

 public static void main(String[] args) {
 SwingUtilities.invokeLater(new Runnable() {
 @Override
 public void run() {
 JFrame f = new JFrame();
 JPanel p = new JPanel();
 ToggleLabel tl = new ToggleLabel("hello");
 p.add(tl);
 tl.setBackground(Color.GREEN);
 tl.setEnabled(false);
 f.add(p);
 f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
 f.pack();
 f.setVisible(true); 
 }
 });
 }

 private static class ToggleLabel extends JLabel {

 private boolean toggle;

 public ToggleLabel(String s) {
 super(s);
 }

 @Override
 public void setEnabled(boolean toggle) {
 this.toggle = toggle;
 System.out.println("I am used");

 }
 @Override
 public boolean isEnabled() {
 return toggle;
 }
 }

}
</code></pre>

As you can see, "I am used" is printed, and the program, when running, look like this:

<img src="https://i.stack.imgur.com/kQJnv.png" alt="enter image description here">

blocks|key|869083|text|您的setEnabled()覆盖在print语句所指出的位置工作。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|869084|要防止组件被禁用，请覆盖isEnabled()并返回true：|869085|+public+boolean+isEnabled()+{+
++++return+true;
+}|code-block|syntax|javascript|869086|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|L|8|@]|9|@]|A|$]]|$1|D|3|E|5|F|7|M|8|@]|9|@]|A|$G|H]]|$1|I|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|J|$]]

Your setEnabled() override is working at noted by the print statement. 
To prevent a component from being disabled override isEnabled() and return true:

<pre><code> public boolean isEnabled() { 
 return true;
 }
</code></pre>

blocks|key|5314973|text|如果您的问题是前景或背景颜色不是您想要的颜色，请向setForeground或setBackground添加重写，在该方法中放置断点并通过调试器运行它。然后在命中断点时查看堆栈，以确定问题所在。有时，我发现是对setEditable的调用导致了我的问题。HTH和好运;)|type|unstyled|depth|inlineStyleRanges|entityRanges|data|5314974|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|D|8|@]|9|@]|A|$]]|$1|B|3|-4|5|6|7|E|8|@]|9|@]|A|$]]]|C|$]]

If your problem is that the foreground or background colour is not what you want, add an override to setForeground or setBackground, put a breakpoint in that method and run it through the debugger. Then look at your stack when the breakpoint is hit to determine the problem. Sometimes it's calls to setEditable that I've found are causing me problems. HTH and good luck ;)

blocks|key|1891223|text|我注意到，在不同的场合，我在自己的组件(我通常从JPanel扩展)上编写的被覆盖的setEnabled方法在实例化时被调用。当然，我自己的构造函数没有显式地调用它。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1891224|因此，这意味着JPanel或其祖先之一在其构造函数中调用setEnabled+(可能是间接的)。|1891225|覆盖在祖先的构造函数中调用的方法是危险的，也许这就是问题的原因。有关此问题的更多信息，请参阅What's+wrong+with+overridable+method+calls+in+constructors?。|offset|length|1891226|entityMap|0|LINK|mutability|MUTABLE|url|https://stackoverflow.com/questions/3404301/whats-wrong-with-overridable-method-calls-in-constructors^0|0|0|1A|1N|0|0^^$0|@$1|2|3|4|5|6|7|P|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|Q|8|@]|9|@]|A|$]]|$1|D|3|E|5|6|7|R|8|@]|9|@$F|S|G|T|1|U]]|A|$]]|$1|H|3|-4|5|6|7|V|8|@]|9|@]|A|$]]]|I|$J|$5|K|L|M|A|$N|O]]]]

I noticed, on different occasions, that the overriden setEnabled method I wrote on my own components (I usually extends from JPanel) was called at instanciation time. Of course my own constructor didn't call it explicitly.

So, this means that JPanel or one of its ancestors calls setEnabled (maybe indirectly) in its constructor.

It is dangerous to override a method that is called in an ancestor's constructor, maybe this is the cause of your problem. See <a href="https://stackoverflow.com/questions/3404301/whats-wrong-with-overridable-method-calls-in-constructors">What&#39;s wrong with overridable method calls in constructors?</a> for more infos about this issue.

blocks|key|5315038|text|启用/禁用的外观由所选外观的组件的UI委托控制。例如，按钮的委托通常派生自javax.swing.plaf.ButtonUI。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|5315039|entityMap|0|LINK|mutability|MUTABLE|url|http://docs.oracle.com/javase/7/docs/api/javax/swing/plaf/ButtonUI.html^0|11|P|11|P|0|0^^$0|@$1|2|3|4|5|6|7|N|8|@$9|O|A|P|B|C]]|D|@$9|Q|A|R|1|S]]|E|$]]|$1|F|3|-4|5|6|7|T|8|@]|D|@]|E|$]]]|G|$H|$5|I|J|K|E|$L|M]]]]

The enabled/disabled appearance is controlled by the component's UI delegate for a chosen Look &amp; Feel. For example, a button's delegate typically derives from <a href="http://docs.oracle.com/javase/7/docs/api/javax/swing/plaf/ButtonUI.html" rel="nofollow"><code>javax.swing.plaf.ButtonUI</code></a>.

My goal is to prevent setEnabled in Swing from graying out my JLabels and other JComponents into unreadability. (The reason for this is that I have another solution to indicate enabled status - icons.) 

Based on SO answers to one of my previous questions, I decided to override setEnabled. Yet as you will find below, my overriding of setEnabled still results in components becoming grayed out, despite the lack of any call to super(toggle). Can someone explain why it appears impossible effectively to override setEnabled's behaviour?

<pre><code>public class ToggleLabel extends JLabel {

private boolean toggle;

public ToggleLabel(String text, boolean toggle) {
 super(text);
 setEnabled(toggle);
}

public ToggleLabel(Icon image, boolean toggle) {
 super(image);
 setEnabled(toggle);
}
@Override
public void setEnabled(boolean toggle) {
 this.toggle = toggle;
 System.out.println("I am used");

}
@Override
public boolean isEnabled() {
 return toggle;
}
</code></pre>

}

Why is it impossible effectively to override Swing's setEnabled?

翻译质量差，导致语言生硬或混乱。

没有提供实际的解决方法或示例。

解答不清晰，无法理解或解决问题。

页面排版不美观，阅读体验差。

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我的目标是防止Swing中的setEnabled将我的JLabels和其他JComponents灰显为不可读。(这样做的原因是我有另一个解决方案来指示已启用的状态图标。)基于对我之前一个问题的回答，我决定重写setEnabled。然而，正如您将在下面发现的，我对setEnabled的覆盖仍然会导致组件变灰，尽管没有任何...

问为什么不能有效地覆盖Swing的setEnabled？
EN

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问为什么不能有效地覆盖Swing的setEnabled？EN