java - 将字符串数组中的元素添加到defaultlistmodel中

Question

我尝试通过删除联系人来更新 JList，但它没有像我希望的那样更新 JList。

最初，JList 看起来像这样。

Broadcast //Not allowed to delete this element
Andy
Bobby
Chris
Brad

假设我已使用按钮将 Andy 从列表中删除。它应该显示

Broadcast //Not allowed to delete this element
Bobby
Chris
Brad

相反，它会在 JList 上显示此内容。

contact0
contact2
contact3
contact4

我不知道出了什么问题，我查阅了很多资料。我希望它返回实际姓名，而不是联系人#。代码如下。

private JList<String> listContacts;
private DefaultListModel<String> model;
private String[] contactList;

model = new DefaultListModel<String>();                                                             
contactList = controller.getContacts();
for(String contact : contactList){
    model.addElement(contact);
}
listContacts = new JList<String>();                                                                  
listContacts.setModel(model);

class MyButtonListener5 implements ActionListener{
    public void actionPerformed(ActionEvent e){
        if(listContacts.getSelectedIndex() == 0){
            controller.displayMsg("Can't delete broadcast.\n");
        }
        else if(listContacts.getSelectedIndex() > 0){
            controller.displayMsg("You tried to delete " + listContacts.getSelectedValue() +".\n");
            model.remove(listContacts.getSelectedIndex());
            listContacts.setModel(model);
        }
        else{
            controller.displayMsg("No contact to delete. Please select one.\n");
        }
    }
}

这是用于 contactList 的 getContacts。该方法位于 Controller 类中。我希望这能澄清我遇到麻烦的原因。

public String[] getContacts(){
    Contact[] contacts = new Contact[5];
    String[] names = new String[5];
    for(int i = 0; i < 5; i++){
        contacts[i] = new Contact("contact" + i);
        names[i] = contacts[i].getName();
    }
    return names;
}

这是在我的联系人类(class)中。

private String name;
private String nickname;

public Contact(){
    name = "";
    nickname = "";
}
public Contact(String name){
    this.name = name;
}
public void setName(String name){
    this.name = name;
}
public String getName(){
    return name;
}
@Override
public String toString(){
    return this.getName();
}

Answer 1

我认为您可以通过重写 Contact 类中的 toString() 方法来解决此问题。

@Override
public String toString() {
    return this.getName();
}

然后您可以返回联系人而无需 .getName() 并直接将其添加到列表中。 I recommend you taking a look at this example.

private JList listContacts;
private DefaultListModel model;
private Contact[] contactList;

model = new DefaultListModel();                                                             
contactList = controller.getContacts();
for(Contact contact : contactList){
    model.addElement(contact);
}
listContacts = new JList();                                                                  
listContacts.setModel(model);

class MyButtonListener5 implements ActionListener{
    public void actionPerformed(ActionEvent e){
        if(listContacts.getSelectedIndex() == 0){
            controller.displayMsg("Can't delete broadcast.\n");
        }
        else if(listContacts.getSelectedIndex() > 0){
            controller.displayMsg("You tried to delete " + listContacts.getSelectedValue() +".\n");
            model.remove(listContacts.getSelectedIndex());
            listContacts.setModel(model);
        }
        else{
            controller.displayMsg("No contact to delete. Please select one.\n");
        }
    }
}

还有你的 getContacts() 方法:

public Contact[] getContacts(){
    Contact[] contacts = new Contact[5];
    contacts[0] = "Broadcast";
    contacts[1] = "Andy";
    contacts[2] = "Bobby";
    contacts[3] = "Chris";
    contacts[4] = "Brad";

    return contacts;
}