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Re: Long delay when using JComboBox.setSelectedIndex() ??

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kedwa...@gmail.com wrote:
> I am attempting to load 5000 employee items into a jcombobox, and then setSelectedIndex, but I am getting a odd delay in the gui after setting the selectedIndex
> 
> 1) If I load the 5000 employee names using a simple vector, it works fine. When I call 

'vector' or "vector" or 'Vector'?

> setSelectedIndex(5), it sets the combobox to the 5th element, very quickly. This works fine:
> 
>  while ((line = input.readLine()) != null) {

This is a slow action on the EDT. Bad.

>                 StringTokenizer st = new StringTokenizer(line, "|");
>                 lastName = st.nextToken().trim();
>                 firstName = st.nextToken().trim();
>                 id = Integer.parseInt(st.nextToken().trim());

'lastName, 'firstName', and 'id' should be declared locally to the loop.

>                  comboBoxItems.add(lastName);}
>                 mybox1.setModel(new javax.swing.DefaultComboBoxModel(model));
>                 mybox1.setSelectedIndex(5);
> 
> 2)HOWEVER, if I load an employee object into a mapped vector, and then setSelectedIndex(5), I DO 

What is a "mapped vector"?

> see it instantly set the GUI combobox to the 5th item, BUT then there is a LOOOONG delay in the gui (1 minute or more) before it allows me to do anything further in the gui
> 
>  while ((line = input.readLine()) != null) {

This is a slow action on the EDT. Bad.

>                 StringTokenizer st = new StringTokenizer(line, "|");
>                 lastName = st.nextToken().trim();
>                 firstName = st.nextToken().trim();
>                 id = Integer.parseInt(st.nextToken().trim());
>                 empBuffer=  new Employee(id, lastName );

'lastName, 'firstName', 'id' and 'empBuffer' should be declared locally to the loop.

>                 map.put(empBuffer.getId()+"",empBuffer ); 
>                 count++; }
>                 
>              model.addAll(map.values()); 
>              Collections.sort(model); 
>              mybox1.setModel(new javax.swing.DefaultComboBoxModel(model));
>              mybox1.setSelectedIndex(5);
> 
> public class Employee implements Comparable { 
>          private int id; 
>          private String name; 
> 
>          public Employee(int id, String name) { 
>              this.id = id; 
>              this.name = name; 
>          } 
> 
>          public String getName() { 
>              return name; 
>          } 
> 
>          public int getId() { 
>              return id; 
>          } 
> 
>          public int compareTo(Object emp) { 
>              return getName().compareTo(((Employee)emp).getName()); 
>          } 
> 
>          public String toString() { 
>              return getName()+","+getId(); 
>          } 
>      }

You should override 'equals()' to match 'compareTo()' so the model will work right.

kedwa...@gmail.com wrote:
> CORRECTION, both examples have the same problem. I thought the first example was working, but in each case AFTER I call setSelectedIndex, the GUI DOES quickly go to the item in the combobox , but then the whole gui hangs for about a minute ???? Why? If I replace the combobox with a jtextfield, it works without delay...

How long does 'input.readLine()' take, and why are you doing it on the EDT?

I/O is much slower than CPU activity. You are causing the GUI to wait for 5000 lines of read. Bad.

Don't do it on the EDT.

-- 
Lew

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Long delay when using JComboBox.setSelectedIndex() ?? kedward777@gmail.com - 2012-12-05 09:27 -0800
  Re: Long delay when using JComboBox.setSelectedIndex() ?? kedward777@gmail.com - 2012-12-05 10:08 -0800
    Re: Long delay when using JComboBox.setSelectedIndex() ?? Lew <lewbloch@gmail.com> - 2012-12-05 10:35 -0800
      Re: Long delay when using JComboBox.setSelectedIndex() ?? kedward777@gmail.com - 2012-12-05 10:46 -0800
        Re: Long delay when using JComboBox.setSelectedIndex() ?? Lew <lewbloch@gmail.com> - 2012-12-05 11:31 -0800
        Re: Long delay when using JComboBox.setSelectedIndex() ?? Roedy Green <see_website@mindprod.com.invalid> - 2012-12-05 16:16 -0800
          Re: Long delay when using JComboBox.setSelectedIndex() ?? Lew <lewbloch@gmail.com> - 2012-12-05 16:34 -0800
            Re: Long delay when using JComboBox.setSelectedIndex() ?? Knute Johnson <nospam@knutejohnson.com> - 2012-12-05 16:40 -0800
              Re: Long delay when using JComboBox.setSelectedIndex() ?? Lew <lewbloch@gmail.com> - 2012-12-05 16:58 -0800
            Re: Long delay when using JComboBox.setSelectedIndex() ?? Roedy Green <see_website@mindprod.com.invalid> - 2012-12-06 15:32 -0800
              Re: Long delay when using JComboBox.setSelectedIndex() ?? Lew <lewbloch@gmail.com> - 2012-12-06 18:04 -0800
  Re: Long delay when using JComboBox.setSelectedIndex() ?? Knute Johnson <nospam@knutejohnson.com> - 2012-12-05 16:15 -0800
  Re: Long delay when using JComboBox.setSelectedIndex() ?? Gene Wirchenko <genew@telus.net> - 2012-12-12 18:15 -0800

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