动态添加复选框到面板

Question

我希望使用来自本体的预生成实体列表中的标签动态生成复选框。我编写了代码来生成复选框并将它们添加到面板中。但是，即使将setVisible设置为true，复选框也不会显示。请帮忙查看我的代码，看看是否有遗漏的内容。

public class ConceptsSelection extends javax.swing.JFrame {

/**
 * Creates new form ConceptsSelection
 */
public ConceptsSelection() {    
    initComponents();
}

Index in = new Index();
ArrayList<String> enti = new ArrayList<>();
private JCheckBox chk;
Set<OWLEntity> entities = new HashSet<OWLEntity>();
ArrayList<String> ents = new ArrayList<>();
JPanel panel;
private ArrayList<String> titles;
private ArrayList checks; //array of checkboxes
String prefix = "http://www.semanticweb.org/tobiomojola/ontologies/2018/0/untitled-ontology-42#";

public void setOntName()
{
    jTextField1.setText(in.fname.toString());
}

public int randomize()
{
    int len = ents.size();
    int result = (int)Math.ceil(Math.random() * len-1);
    return result;
}

public void addEnt(OWLOntology a)
{
    OWLOntology ontol = a;
    for(OWLSubClassOfAxiom f : ontol.getAxioms(AxiomType.SUBCLASS_OF))
    {
        if (f.getSuperClass() instanceof OWLClass && f.getSubClass() instanceof OWLClass)
        {
            //System.out.println(f.getSubClass() + " extends " + f.getSuperClass());
            entities.add((OWLEntity) f.getSubClass());
        }
    }
    for(OWLEntity e : entities)
    {
        ents.add(e.getIRI().toString().replaceAll(prefix, ""));
    }
}

private void jButton2ActionPerformed(java.awt.event.ActionEvent evt) {                                         
    fillArray();
    createChecks(jPanel1);
}                                        

private void createChecks(Component x)
{
    jPanel1.setVisible(true);
    for(int i=1; i<6; i++)
    { 
        int b = randomize();
        chk = new JCheckBox(titles.get(b));
        jPanel1.add(chk);
        jPanel1.setVisible(true);
        chk.setVisible(true);

    }

    {
        //create a new checkbox for each string in the array
        chk=new JCheckBox(s);

        //add the checkbox to the panel
        jPanel1.add(chk);
        //add the checkbox to the array of checkboxes
        checks.add(chk);
    }

}

public void fillArray()
{
     titles=new ArrayList();
     for(String e : ents)
     {
         titles.add(e);
     }
}