我有我的JTable密码字段编辑器。 我想如果文本长度小于8位,当用户点击编辑另一个字段中显示一个错误消息。 我试图专注的听众。 但它不工作。 请帮助我,因为我刚开始用的Java Swing干活。
class PasswordEditor extends DefaultCellEditor
{
TextBox m_passWord = new TextBox();
public PasswordEditor() {
super(new TextBox());
}
@Override
public Object getCellEditorValue() {
return this.m_passWord.getText();
}
@Override
public Component getTableCellEditorComponent(JTable table,
Object value, boolean isSelected, int row, int column) {
Object fieldValue = value;
if(null == fieldValue)
fieldValue = Constants.EMPTY_STRING;
this.m_passWord.addInputMethodListener(new InputMethodListener() {
@Override
public void inputMethodTextChanged(InputMethodEvent event)
{
// TODO Auto-generated method stub
}
@Override
public void caretPositionChanged(InputMethodEvent event)
{
// TODO Auto-generated method stub
}
})
this.m_passWord.addFocusListener(new FocusListener() {
@Override
public void focusLost(FocusEvent e)
{
if (!e.isTemporary()) {
String content = PasswordEditor.this.m_passWord.getText();
System.out.println((content));
}
}
@Override
public void focusGained(FocusEvent e)
{
//TODO init
}
});
this.m_passWord.setEditable(true);
this.m_passWord.setText(fieldValue.toString());
return this.m_passWord;
}
}
据我了解的问题,这是关于在编辑器中验证输入(模型保护自己免受无效值是另一个故事,IMO)和通知用户关于他/她的错误时,他/她尝试提交的输入。
这样做的一个简单的方法是使用InputVerifier:
- 实现它的方法验证验证规则
- 实施其shouldYieldFocus通知
- 子类DefaultCellEditor并覆盖其stopCellEditing调用shouldYieldFocus并返回结果(又名:拒绝提交编辑)
一些代码片段:
final InputVerifier iv = new InputVerifier() {
@Override
public boolean verify(JComponent input) {
JTextField field = (JTextField) input;
return field.getText().length() > 8;
}
@Override
public boolean shouldYieldFocus(JComponent input) {
boolean valid = verify(input);
if (!valid) {
JOptionPane.showMessageDialog(null, "invalid");
}
return valid;
}
};
DefaultCellEditor editor = new DefaultCellEditor(new JTextField()) {
{
getComponent().setInputVerifier(iv);
}
@Override
public boolean stopCellEditing() {
if (!iv.shouldYieldFocus(getComponent())) return false;
return super.stopCellEditing();
}
@Override
public JTextField getComponent() {
return (JTextField) super.getComponent();
}
};
JTable table = new JTable(10, 2);
table.setDefaultEditor(Object.class, editor);
覆盖stopCellEditing()和执行里面的情况。
class PasswordEditor extends DefaultCellEditor
{
TextBox m_passWord = new TextBox();
public PasswordEditor() {
super(new TextBox());
}
@Override
public boolean stopCellEditing()
{
if(getCellEditorValue().toString().length() < 8)
{
JOptionPane.showMessageDialog(UsmUserView.this.m_Parent, "Password Must Be 8 Bytes Long !! Please Check");
return false;
}
fireEditingStopped();
return true;
}
@Override
public Object getCellEditorValue() {
return this.m_passWord.getText();
}
@Override
public Component getTableCellEditorComponent(JTable table,
Object value, boolean isSelected, int row, int column) {
Object fieldValue = value;
if(null == fieldValue)
fieldValue = Constants.EMPTY_STRING;
this.m_passWord.setEditable(true);
this.m_passWord.setText(fieldValue.toString());
return this.m_passWord;
}
}
重写stopCellEditing()和u可以尝试下面的代码以获取错误单元格的焦点。
class PasswordEditor extends DefaultCellEditor
{
private TextBox m_passWord = new TextBox();
public PasswordEditor() {
super(new TextBox());
}
@Override
public boolean stopCellEditing()
{
if(getCellEditorValue().toString().length() < 8)
{
// Text box will get the focus and will shown in Red line as border for that cell.
TextBox aTextBox = (TextBox)getComponent();
aTextBox.setBorder(new LineBorder(Color.red));
aTextBox.selectAll();
aTextBox.requestFocusInWindow();
JOptionPane.showMessageDialog(UsmUserView.this.m_Parent, "Password Must Be 8 Bytes Long !! Please Check");
return false;
}
return super.stopCellEditing();
}
@Override
public Object getCellEditorValue() {
return this.m_passWord.getText();
}
@Override
public Component getTableCellEditorComponent(JTable table,
Object value, boolean isSelected, int row, int column) {
Object fieldValue = value;
if(null == fieldValue)
fieldValue = Constants.EMPTY_STRING;
this.m_passWord.setEditable(true);
this.m_passWord.setText(fieldValue.toString());
return this.m_passWord;
}
}