How do I populate a JComboBox with an ArrayList?

问题

I need to populate a JComboBox with an ArrayList. Is there any way to do this?

回答1:

Use the toArray() method of the ArrayList class and pass it into the constructor of the JComboBox

See the JavaDoc and tutorial for more info.

回答2:

Elegant way to fill combo box with an array list :

List<String> ls = new ArrayList<String>(); 
jComboBox.setModel(new DefaultComboBoxModel(ls.toArray()));

回答3:

I don't like the accepted answer or @fivetwentysix's comment regarding how to solve this. It gets at one method for doing this, but doesn't give the full solution to using toArray. You need to use toArray and give it an argument that's an array of the correct type and size so that you don't end up with an Object array. While an object array will work, I don't think it's best practice in a strongly typed language.

String[] array = arrayList.toArray(new String[arrayList.size()]);
JComboBox comboBox = new JComboBox(array);

Alternatively, you can also maintain strong typing by just using a for loop.

String[] array = new String[arrayList.size()];
for(int i = 0; i < array.length; i++) {
    array[i] = arrayList.get(i);
}
JComboBox comboBox = new JComboBox(array);

回答4:

DefaultComboBoxModel dml= new DefaultComboBoxModel();
for (int i = 0; i < <ArrayList>.size(); i++) {
  dml.addElement(<ArrayList>.get(i).getField());
}

<ComboBoxName>.setModel(dml);

Understandable code.Edit<> with type as required.

回答5:

I believe you can create a new Vector using your ArrayList and pass that to the JCombobox Constructor.

JComboBox<String> combobox = new JComboBox<String>(new Vector<String>(myArrayList));

my example is only strings though.

回答6:

Check this simple code

import java.util.ArrayList;
import javax.swing.JComboBox;
import javax.swing.JFrame;


public class FirstFrame extends JFrame{

    static JComboBox<ArrayList> mycombo;

    FirstFrame()
    {
        this.setSize(600,500);
        this.setTitle("My combo");
        this.setLayout(null);

        ArrayList<String> names=new ArrayList<String>();   
        names.add("jessy");
        names.add("albert");
        names.add("grace");
        mycombo=new JComboBox(names.toArray());
        mycombo.setBounds(60,32,200,50);
        this.add(mycombo);
        this.setVisible(true); // window visible
    }   

    public static void main(String[] args) {

        FirstFrame frame=new FirstFrame();  

    }

}

回答7:

By combining existing answers (this one and this one) the proper type safe way to add an ArrayList to a JComboBox is the following:

private DefaultComboBoxModel<YourClass> getComboBoxModel(List<YourClass> yourClassList)
{
    YourClass[] comboBoxModel = yourClassList.toArray(new YourClass[0]);
    return new DefaultComboBoxModel<>(comboBoxModel);
}

In your GUI code you set the entire list into your JComboBox as follows:

DefaultComboBoxModel<YourClass> comboBoxModel = getComboBoxModel(yourClassList);
comboBox.setModel(comboBoxModel);

回答8:

i think that is the solution

ArrayList<table> libel = new ArrayList<table>();
try {
SessionFactory sf = new Configuration().configure().buildSessionFactory();
Session s = sf.openSession();
s.beginTransaction();

String hql = "FROM table ";

org.hibernate.Query query = s.createQuery(hql);
libel= (ArrayList<table>) query.list();
Iterator it = libel.iterator();
while(it.hasNext()) {
table cat = (table) it.next();

cat.getLibCat();//table colonm getter


combobox.addItem(cat.getLibCat());
}
s.getTransaction().commit();
s.close();
sf.close();
} catch (Exception e) {
System.out.println("Exception in getSelectedData::"+e.getMessage());

来源：https://stackoverflow.com/questions/1291704/how-do-i-populate-a-jcombobox-with-an-arraylist

标签

java

swing

arraylist

jcombobox