Ask help about variable range

Question

1.if I define a variable at the start of the class: private JList flightsList;
2.then write a method :public void doQuery( )
String startAirport = (String)from.getSelectedItem();
String endAirport = (String)to.getSelectedItem();
String timeDate = date.getText();
if( manager.getFlights(startAirport, endAirport,timeDate) != null )
     Flight [] flightQuery = manager.getFlights(startAirport, endAirport,timeDate);
     int length = flightQuery.length;
     String [] number = new String[length];
     System.arraycopy(flightQuery,0,number,0,length);
     //flightsList = new JList( number );
3.then make a constructor,I want in the constructor invoke the method doQuery( ) ,then use
code: flightsList = new JList( number );
     contents.add( new JScrollPane( flightsList) , BorderLayout.CENTER );
I want to put arryaay number in the flightsList,then create a JScrollPane show the arraay number.
But it does not work.I know it is the variable range,how to pass the number into the flightsList?
I have thought about it for a long time.
Please help me,thanks!

Answer 1

I mean:
example:
public class look extends JFrame {
//if I define a variable at the start of the class:
private JList flightsList;
//2.then write a method :public void doQuery( )
String startAirport = (String)from.getSelectedItem();
String endAirport = (String)to.getSelectedItem();
String timeDate = date.getText();
if( manager.getFlights(startAirport, endAirport,timeDate) != null )
Flight [] flightQuery = manager.getFlights(startAirport, endAirport,timeDate);
int length = flightQuery.length;
String [] number = new String[length];
System.arraycopy(flightQuery,0,number,0,length);
//flightsList = new JList( number );
3.then make a constructor,I want in the constructor invoke the method doQuery( ) ,
public gui
//use code
flightsList = new JList( number );
contents.add( new JScrollPane( flightsList) , BorderLayout.CENTER );
in sort I want to put array number in the jlist( flightsList),then create a JScrollPane show the arraay number(number).
//Your constructor assigns the private variable the value of what it is passed, then you can use it in other functions in the class.
Is that what you are asking?
no,I mean assingns a private variable,then write a method ,then invoke the method to put array number in the private variable.