我有一个可能很简单的问题（尽管我已经完成了搜索）。我有一个数组列表，只需单击 JButton 即可更新。我有 toString() 这个数组列表，这样我就可以将它添加到 textarea.setText(xx.toString() 以便我可以在滚动窗格上显示。问题是每次添加一个元素时，textarea 都会显示数组，然后新的更新数组，这意味着文本每次都会翻倍。还有其他方法吗？谢谢，知道这是个愚蠢的问题
public nameFrame()
{
super("Name Generator");
JPanel background = new JPanel();
background.setLayout(new BoxLayout( background, BoxLayout.X_AXIS ) );
name = new ArrayList<String>();
getContentPane().add(background);
Box verticalBack = Box.createVerticalBox();
Box horizbox1 = Box.createHorizontalBox();
Box horizboxmid = Box.createHorizontalBox();
Box horizbox2 = Box.createHorizontalBox();
Box verticalbox1 =Box.createVerticalBox();
Box verticalbox2 = Box.createVerticalBox();
getContentPane();
background.add(verticalBack);
verticalBack.add(horizbox1);
horizbox1.add(verticalbox1);
horizbox1.add(verticalbox2);
verticalBack.add(horizboxmid);
verticalBack.add(horizbox2);
JButton maleName = new JButton("MALE");
JButton femaleName = new JButton("FEMALE");
JButton clearLog = new JButton("CLEAR LIST");
JButton closeApp = new JButton("CLOSE");
verticalbox1.add(maleName);
verticalbox1.add(femaleName);
verticalbox2.add(clearLog);
verticalbox2.add(closeApp);
final JScrollPane listName = new JScrollPane();
listName.setVerticalScrollBarPolicy(ScrollPaneConstants.VERTICAL_SCROLLBAR_ALWAYS);
horizbox2.add(listName);
final JTextArea nameDisplayList = new JTextArea();
nameDisplayList.setSize(300, 300);
listName.add(nameDisplayList);
listName.setViewportView(nameDisplayList);
nameDisplayList.setEditable(false);
nameDisplayList.setVisible(true);
stringLog = Arrays.toString(name.toArray()).replaceAll("\\[|\\]", "").replaceAll(", ","\n");
final StringBuilder sb = new StringBuilder();
for(String s : name)
{
sb.append(s);
sb.append("\n");
}
nameDisplayList.setText(sb.toString());
///listName.repaint();
///listName.revalidate();
nameDisplayList.setText(sb.toString());
maleName.addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent event)
{
{
try {
Scan = new Scanner(new File("MaleNames.txt"));
ArrayList<String> MaleFirstNames = new ArrayList<String>();
while(Scan.hasNext())
{
MaleFirstNames.add(Scan.next());
}
Scan.close();
int Mindex = new Random().nextInt(MaleFirstNames.size());
firstName = MaleFirstNames.get(Mindex);
Scan = new Scanner(new File("Surnames.txt"));
ArrayList<String> SurnameList = new ArrayList<String>();
while(Scan.hasNext())
{
SurnameList.add(Scan.next());
}
Scan.close();
int Sindex = new Random().nextInt(SurnameList.size());
surName = SurnameList.get(Sindex);
fullName = String.format("%s\t%s%n", firstName, surName);
name.add(fullName);
//indexPoint++;
//System.out.println(name);
nameDisplayList.revalidate();
nameDisplayList.repaint();
for(String s : name)
{
sb.append(s);
sb.append("\n");
}
nameDisplayList.setText(sb.toString());
}
catch (FileNotFoundException e)
{
e.printStackTrace();
}
}
}
});
femaleName.addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent event)
{
{
try {
Scan = new Scanner(new File("FemaleNames.txt"));
ArrayList<String> FemaleFirstNames = new ArrayList<String>();
while(Scan.hasNext())
{
FemaleFirstNames.add(Scan.next());
}
Scan.close();
int Findex = new Random().nextInt(FemaleFirstNames.size());
firstName = FemaleFirstNames.get(Findex);
Scan = new Scanner(new File("Surnames.txt"));
ArrayList<String> SurnameList = new ArrayList<String>();
while(Scan.hasNext())
{
SurnameList.add(Scan.next());
}
Scan.close();
int Sindex = new Random().nextInt(SurnameList.size());
surName = SurnameList.get(Sindex);
fullName = String.format("%s\t%s%n", firstName, surName);
name.add(indexPoint, fullName);
}
catch (FileNotFoundException e)
{
e.printStackTrace();
}
}
}
});
clearLog.addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent event)
{
{
do
{
name.add(name.size(), " ");
indexPoint--;
}while(indexPoint != 0);
}
}
});
}
}