Java 新手问题:如何从同一类中的另一个方法或其他方法访问已创建的JComboBox实例
如果我有: 甲级{Java 新手问题:如何从同一类中的另一个方法或其他方法访问已创建的JComboBox实例,java,swing,object,methods,jcombobox,Java,Swing,Object,Methods,Jcombobox,如果我有: 甲级{ // bunch of stuff here public void intitialize() { // bunch of stuff here JComboBox jBox = new JComboBox() formatBox.addItem(//some objects added here)) //I do the rest of my business in this intitialize method
// bunch of stuff here
public void intitialize() {
// bunch of stuff here
JComboBox jBox = new JComboBox()
formatBox.addItem(//some objects added here))
//I do the rest of my business in this intitialize method
}
}
如果我想添加另一个调用时可以在jBox上操作的方法,我该怎么做?此代码不起作用:
Class A {
// bunch of stuff here
public void intitialize() {
// bunch of stuff here
JComboBox jBox = new JComboBox()
formatBox.addItem(//some objects added here))
//I do the rest of my business in this intitialize method
}
//newly added method
public void anotherMethod(){
jBox.removeItem(//some item here)
}
}
有哪些正确的编写方法允许从类或其他类的不同方法访问jBox?为什么不这样做呢?将JComboBox定义为类a中的字段,并删除
initialize
方法中的类型声明:
Class A {
private JComboBox jBox;
// bunch of stuff here
public void intitialize() {
// bunch of stuff here
jBox = new JComboBox()
formatBox.addItem(//some objects added here))
//I do the rest of my business in this intitialize method
}
//newly added method
public void anotherMethod(){
jBox.removeItem(//some item here)
}
}
将JComboBox定义为类a中的字段,并删除
initialize
方法中的类型声明:
Class A {
private JComboBox jBox;
// bunch of stuff here
public void intitialize() {
// bunch of stuff here
jBox = new JComboBox()
formatBox.addItem(//some objects added here))
//I do the rest of my business in this intitialize method
}
//newly added method
public void anotherMethod(){
jBox.removeItem(//some item here)
}
}
使用实例变量并将
JComboBox
存储在那里。如果您想从另一个类访问它,您可能应该创建一个publicgetJBox()
方法,这样实例方法就可以是私有的
例如:
Class A {
private JComboBox jBox;
public void intitialize() {
jBox = new JComboBox()
formatBox.addItem(//some objects added here))
//I do the rest of my business in this intitialize method
}
public JComboBox() getJBox() {
return jBox;
}
}
使用实例变量并将
JComboBox
存储在那里。如果您想从另一个类访问它,您可能应该创建一个publicgetJBox()
方法,这样实例方法就可以是私有的
例如:
Class A {
private JComboBox jBox;
public void intitialize() {
jBox = new JComboBox()
formatBox.addItem(//some objects added here))
//I do the rest of my business in this intitialize method
}
public JComboBox() getJBox() {
return jBox;
}
}
谢谢:)。你们都给出了相同的答案,亚当也回答了我的另一个问题,这就是为什么我接受了他的答案。我希望能够接受这两个答案。谢谢:)。你们都给出了相同的答案,亚当也回答了我的另一个问题,这就是为什么我接受了他的答案。我希望这两个答案都能接受。