1
我想調用showArrayList方法，但它不斷給我ContactList無法轉換爲java.util.ArrayList<Contact>。我究竟做錯了什麼？到目前爲止，我有這樣的：試圖調用showArrayList方法
public class ControlPanel extends JPanel implements ActionListener
{
// Fields (instance variables/attributes)
private JLabel phoneNumberLabel; // a reference to the phoneNumberLabel that is displayed in the PhoneNumberDisplayPanel.
private Contact nameAndNumber; // Holds the name and number for a phone Contact.
// Contact lists;
private ContactList contacts; // Encapsulates a list of saved contacts, ie.e phone Contacts.
private ContactList callsMade; // Encapsulates a list of calls made, i.e. phone Contacts.
private void findNumber()
{
if(nameLabel.getText().equals(contacts.searchByName(nameLabel.getText())))
showArrayList(contacts,nameLabel.getText());
else
showArrayList(contacts, "");
}
的showArrayList方法是：
public void showArrayList(ArrayList<Contact> list, String title)
{
int x = 410;
int y = 445;
int width = 350;
int height = 200;
boolean disableCloseButton = false;
Window newWindow = new Window(title, x, y, width, height, Color.RED, disableCloseButton);
{
newWindow.println("No contact information saved");
}
else
{
for (Contact c: list)
{
newWindow.println(c.toString());
}
}
現在我做到這一點，它編譯：
private void findNumber()
{
ArrayList<Contact> list = new ArrayList<Contact>();
if(nameLabel.getText().equals(contacts.searchByName(nameLabel.getText())))
showArrayList(list,nameLabel.getText());
else
showArrayList(list, "");
}
我ContactList類：
public class ContactList
{
private ArrayList<Contact> list;
/**
* Constructor for a ContactList, to initialize the list from file.
*
* @param fileName a reference to an existing file
* @param window a reference to an existing window to display the list contacts
*/
public ContactList(String fileName, Window window)
{
list = new ArrayList<Contact>();
File file = new File(fileName);
// Remark. A file needs to have been written, before it can be read.
if (file.exists())
{
try
{
Scanner fileReader = new Scanner(file);
readFile(fileReader);
window.print(this.toString());
}
catch(FileNotFoundException error) // could not find file
{
System.out.println("File not found ");
}
}
}
/********************************************************************
* Searches the list for a particular contact,
* comparing this name and number (in lower case)
* with the contact name and number (in lower case).
*
* @param contact
* @return returns true if the contact is found, otherwise false
*/
public boolean found(Contact contact)
{
for(Contact c: list){
if(c == contact){
return true;
}
}
return false;
}
/******************************************************************
* Adds one contact to the list
*
* @param contact
*/
public void add(Contact contact)
{
list.add(contact);
}
/******************************************************************
* searches the list for each name that contains the specified substring
*
* @param substring
* @return returns the result as an ArrayList
*/
public ArrayList<Contact> searchByName(String substring)
{
ArrayList<Contact> l = new ArrayList<Contact>();
for(Contact c: list){
if(c.getName() == substring){
l.add(c);
}
}
return l;
}
告訴我們在哪兒聲明'contacts' – 2014-11-09 05:01:22
編輯它變成你的問題，而不是作爲一個評論（讀取硬盤作爲註釋）。 'contacts'是一個'ContactList'，而不是'ArrayList'，這就是爲什麼你的方法不接受它 –
2014-11-09 05:08:07
我已經嘗試了一切。我試過我的實際ArrayList（從我的ContactList類）。也許我應該創建一個新的ArrayList？ – phoenix47 2014-11-09 05:11:40