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POJPanel.addComponentListener does not work when the listener is a class variable
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  1. POJPanel.addComponentListener does not work when the listener is a class variable
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    copied!<p>I have a public class which has the following method and instance variable:</p> <pre><code>public void setImagePanel(JPanel value) { imagePanel = value; if (imagePanel != null) { //method 1 : works imagePanel.addComponentListener(new ComponentAdapter() { public void componentResized(ComponentEvent evt) { System.out.println("Here 1"); } }); //method 2 : does not work panelResizeListener = new ResizeListener(); imagePanel.addComponentListener(panelResizeListener); //method 3 : works //ResizeListener listener = new ResizeListener(); //imagePanel.addComponentListener(listener); //method 4 : works //imagePanel.addComponentListener(new ResizeListener()); //method 5 : does not work -- THIS IS THE DESIRED CODE I WANT TO USE imagePanel.addComponentListener(panelResizeListener); } } public class ResizeListener extends ComponentAdapter { @Override public void componentResized(ComponentEvent evt) { System.out.println("RESIZE 3"); } } private ResizeListener panelResizeListener = new ResizeListener(); private static JPanel imagePanel; </code></pre> <p>Each of the methods above correspond the to code immediately below until the next //method comment. What i don't understand is why i can't use the class instance variable and add that to the <code>JPanel</code> as a component listener. </p> <p>What happens in the cases above where i say that the method does not work is that i don't get the <code>"RESIZE 3"</code> log messages. In all cases where i list that it works, then i get the <code>"RESIZE 3"</code> messages.</p> <p>The outer class is public with no other modification except that it implements an interface that i created (which has no methods or variables in common with the methods and variables listed above).</p> <p>If anyone can help me i would greatly appreciate it. This problem makes no sense to me, the code should be identical.</p>
 

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