从Hashmap填充JList并检索键

Question

我如何从一个HashMap填充JList而只在列表中显示值呢？

public void populateListwithCategories(final JList list) {
    try {
        DefaultListModel listModel = new DefaultListModel();
        List<AdvertisementCategory> advertisementCategories = advertisementCategoryProvider.getAdvertisementCategories();
        for (AdvertisementCategory advertisementCategory : advertisementCategories) {               
            int id = advertisementCategory.getId();
            String name = advertisementCategory.getName();
            advertisementCategory.advertisementMap.put(id, name);
            listModel.addElement(advertisementCategory.advertisementMap); 
        }
        list.setModel(listModel);
    } catch (MalformedURLException ex) {
        Logger.getLogger(AdvertisementCategoryController.class.getName()).log(Level.SEVERE, null, ex);
    } catch (IOException ex) {
        Logger.getLogger(AdvertisementCategoryController.class.getName()).log(Level.SEVERE, null, ex);
    }
}

public class AdvertisementCategory {

private int id;
private String name, description;
public List<AdvertisementCategory> advertisementCategories;

public Map<Object, String> advertisementMap = new HashMap<>();

public int getId() {
    return id;
}

public void setId(int id) {
    this.id = id;
}

public String getName() {
    return name;
}

public void setName(String name) {
    this.name = name;
}

public String getDescription() {
    return description;
}

public void setDescription(String description) {
    this.description = description;
}

public AdvertisementCategory(int id, String name, String description) {
    this.id = id;
    this.name = name;
    this.description = description;
}

public AdvertisementCategory(String name, String description) {
    this.name = name;
    this.description = description;
}

public AdvertisementCategory() {

}

public AdvertisementCategory(int id, String name) {
    this.id = id;
    this.name = name;
}

Answer 1

您试图为一个不存在的问题实现一个相当复杂的解决方案。

使用Swing的MVC-principles，您可以将AdvertismentCategory直接添加到列表模型中，并实现ListCellRenderer来从AdvertismentCategory实例提取显示值，该值应该显示在JList本身中。然后，在JList上调用getSelectedValue()将为您提供AdvertismentCategory实例，并且您可以访问它的所有内容。