如何从匿名类中访问封闭的类实例变量？
如何从匿名类的方法中访问instance variables ？
class Tester extends JFrame { private JButton button; private JLabel label; //..some more public Tester() { function(); // CALL FUNCTION } public void function() { Runnable r = new Runnable() { @Override public void run() { // How do I access button and label from here ? } }; new Thread(r).start(); } }
如何从匿名类的方法中访问
instance variables？
如果需要，您只需访问它们：
class Tester extends JFrame { private JButton button; private JLabel label; //..some more public Tester() { function(); // CALL FUNCTION } public void function() { Runnable r = new Runnable() { @Override public void run() { System.out.println("Button's text is: " + button.getText()); } }; new Thread(r).start(); } }
更重要的是：为什么这不适合你？
你要找的是一个完全合格的地址，因为它们没有标记为final
final Runnable r = new Runnable() { public void run() { Tester.this.button // access what you need Tester.this.label // access what you need }};
在构建ActionListeners和其他东西时，您对Anonymous Inner Classes使用相同的访问模式。
这在规范中解释为15.8.4合格 ，这是下选民显然没有阅读的内容。 并没有阅读理解代码。
以下代码可以解释您的格式是IncloseingClassName.this.VariableName;
class Tester extends JFrame { int abc=44;//class variable with collision in name int xyz=4 ;//class variable without collision in name public Tester() { function(); // CALL FUNCTION } public void function() { Runnable r = new Runnable() { int abc=55;//anonymous class variable @Override public void run() { System.out.println(this.abc); //output is 55 System.out.println(abc);//output is 55 System.out.println(Tester.this.abc);//output is 44 //System.out.println(this.xyz);//this will give error System.out.println(Tester.this.xyz);//output is 4 System.out.println(xyz);//output is 4 //output is 4 if variable is declared in only enclosing method //then there is no need of Tester.this.abcd ie you can directly //use the variable name if there is no duplication //ie two variables with same name hope you understood :) } }; new Thread(r).start(); } }